You shall pass! Microbiology final Chapter 19, Chapter 26 Microbial Diseases of the urinary and reproductive systems, Unit 13: Microbial Diseases; Lesson 5: Microbial Diseases of the Digestive System, Microbiology, Exam 4...
Name one function for each of the five classes of antibodies.
- IgG - monomer: Enhances phagocytosis; neutralizes toxins and viruses; protects fetus and newborn - IgM - pentamer: Effective against microorganisms and agglutinating antigens; first antibodies produced in response to initial infection. - IgA - Dimer with secretory component: Localized protection on mucosal surfaces. - IgD - monomer: Presence on B cells functions in initiation of immune response. - IgE - monomer: Allergic reactions; lysis of parasitic worms.
Types of adaptive immunity:
- Naturally acquired active immunity: Resulting from infection - Naturally acquired passive immunity: Transplacental or via colostrum - Artificially acquired active immunity: Injection of Ag (vaccination)-immunization with antigen - Artificially acquired passive immunity: Injection of Ab-injection of antibody containing serum that came from another person or animal.
Food infection
-Viable microbes must be ingested with food or water -organisms could be present during preparation and survive cooking or be inoculated during later handling. -etiological agents are usually gram-negative organisms (Salmonella. Shigella. Vibrio and Escherichia) that produce endotoxins. -Clostridium perfringens- a gram-positive bacterium that causes food infection. -Onset: 12 hrs to 2 weeks. -Duration: Longer than intoxication because the microorganisms are growing in the patient -Treatment: Rehydration
*List and briefly describe, three examples of viral hemorrhagic fever
-Yellow Fever- injected into skin by a mosquito, A. aeypti -early stages of severe cases of the disease: person experiences fever, chills, headache -followed by nausea and vomiting -followed by jaundice- yellowing of the skin (hence the name) -reflects liver damage- results in the deposits of bile pigments in the skin and mucous membranes -mortality rate is high- 20% Dengue- similar but milder viral disease also transmitted by mosquitos -endemic in Caribbean and other tropical envts -fever, severe muscle and joint pain, rash -except for the painful symptoms- lead to the name breakbone fever- classic dengue fever is a relative mild disease and is rarely fatal -severe form of dengue- dengue hemorrhagic fever (DHF)- caused when antibodies froma pervious infection combine w/ the virus. -DHG- can induce shock in the victim (usually a child) and kill in a few hrs -leading cause of death among southeast Asian children -outbreaks also in Mexico, South America, and Caribbean Ebola Hemorrhagic Fever: outbeak in Africa of another highly lethal hemorrhagic fever were caused by ebolaviruses- a filovirus similar to Marburg virus -walls of blood vessels are damaged -virus interferes w/ coagulation -blood continues to leak into surrounding tissue Ebola hemorrhagic fever-mortality approaching 90% -natural host reservoir for the Ebola virus is a cave-dwelling fruit bat- used as food and is not acutely affected by the virus it carries -once human is infected and shedding blood, infection is spread by contact w/ blood and body fluids and in many cases by the reusing of needles used on patients -local custom of washing the body before burial often triggers new infections
Discuss the epidemiology of brucellosis. - What ethnic group in the United States is most commonly affected by brucellosis, and why?
Brucella spp. Aerobic gram-negative rods Brucella abortus (elk, bison, cows) Brucella suis (swine) Brucella melitensis (goats, sheep, camels) Transmitted via milk from infected animals or contact with infected animals Perisists in the reticuloendothelial system; evades phagocytes Undulant fever (malaise, night sweats, muscle aches) Not usually fatal *Hispanics
Types of Plague
Bubonic Plague Septicemin Plague Pneumonic Plague
Hepatitis B
Causative Agent: -Hepatitis B virus -Hepadnaviridae Mode of Transmission: -Parenteral, -sexual contact Site of Infection: -Liver Symptoms: -Anorexia, fever, joint pains, jaundice Prevention: Vaccine: Genetically modified vaccine produced in yeast
Disease: Leishmaniasis Causative Agent: Vector: Treatment:
Causative Agent: -Leishmania Vector: -Sandflies Treatment: -Antimony
Disease: Malaria Causative Agent: Vector: Treatment:
Causative Agent: -Plasmodium Vector: -Anopheles Treatment: -Quinine derivative
Disease: Tularemia Causative Agent: Transmission: Reservoir:
Causative Agent: -Tularemia Transmission: -Skin abrasions, ingestion, inhalation, bites Reservoir: -Rabbits
Disease: Plague Causative Agent: Transmission: Reservoir:
Causative Agent: -Yersinia pestis Transmission: -Flea bites, inhalation Reservoir: -Rodents
Viral gastroenteritis
Causative Agent: -rotavirus or -human calciviruses (the noroviruses) Mode of Transmission: Site of Infection: Lower GI tract Symptoms: Nausea, diarrhea, vomiting Prevention: -live oral administered vaccine was licensed in 2006
Disease: Relapsing fever Causative Agent: Vector: Treatment:
Causative Agent: Borrelia Vector: Soft ticks Treatment: Tetracycline
Disease: Ehrlichiosis Causative Agent: Transmission: Reservoir:
Causative Agent: Ehrlichia spp. Transmission: -Tick bites Reservoir: -Deer
Disease: Dengue Causative Agent: Vector: Treatment:
Causative Agent: Flavivirus Vector: -Aedes aegypti Treatment: None
Disease: Cytomegalic inclusion disease Causative Agent: Transmission: Reservoir:
Causative Agent: HHV-5 Transmission: -Saliva, blood Reservoir: -Humans
Mumps
Causative Agent: Mumps virus Mode of Transmission: -saliva and respiratory secreations (enters through resp tract_ Site of Infection: Parotid glands Symptoms: Inflammation of the parotid glands and fever Prevention: -Vaccination is the best way to prevent mumps. This vaccine is included in the combination measles-mumps-rubella (MMR) and measles-mumps-rubella-varicella (MMRV) vaccines. ... The MMR vaccine protects against currently circulating mumps strains.
TSS
Causative agent: S. aureus Clinical Manifestation: sudden fever and circulatory collapse, high fever, chills, accompanied by vomiting and watery diarrhea, sore throat, severe muscle aches, and sunburn-like rash, if severe drop in blood platelets, renal failure, shock and death Treatment: antibiotics and blood transfusions Transmission:result of exposure from a skin abscess, surgery, or even tattooing or highly absorbent tattoo Prevention: good hygiene
Three ways that a virus can cause cancer
1. Oncogenic activitySome viruses carry an oncogene whose protein product directly causes uncontrolled growth 2. Gene suppressionOther viruses integrate their DNA next to a tumor suppressor gene (TSG), resulting in inactivation of the TSG and leading to uncontrolled cell growth. 3. Gene activationSome viruses integrate their DNA next to a silent growth control gene, resulting in activation of the genes and uncontrolled growth.
How does acute glomerulonephritis occur?
Acute glomerulonephritis results from deposition of antigen-antibody-complement complexes on the basement membrane of kidney glomeruli. It may lead to renal damage in adults.
What purposes does inflammation serve?
Acute inflammation is an organism's response a harmful stimulus, which could be a physical injury, an allergic reaction, or another cause. The inflammation itself is due to increased blood flow to the area, which brings with it plasma proteins (like fibrinogen, which helps clot a wound) and leukocytes (white blood cells, which attempt to remove the stimulus).
Erysipelas
Causative agent: S. pyogenes Clinical Manifestation: igh fever, shaking and chills, and headache Treatment:oral or intravenous antibiotics. Transmission: organisms enter the skin through minor trauma, insect bites, eczema, or superficial incisions. It can also come from the individual's own nasal passages. Prevention: avoiding dry skin and preventing cuts and scrapes
Hutchinsons triad
Affected children often suffer poor bone formation, meningitis a combination of deafness, impaired vision, and notched, peg-shaped teeth
On what continent did the HIV-1 virus arise?
African
Aids Transmission
African green monkey through bite. Unsafe sexual Practices.
Types of hemolysis
Alpha hemolytic streptococci turn the blood agar an olive-green color as a secreted toxin partially destroys the RBCs. Beta hemolytic streptococci produce clear, colorless zones around colonies due to complete destruction of RBCs. Nonhemolytic streptococci have no effect on RBCs and thus cause no change in the blood agar.
Gram-negative sepsis
Also called endotoxin shock Endotoxins (lipopolysaccharides [LPS]) cause a severe drop in blood pressure Antibiotics can worsen the condition by killing bacteria Treatment involves neutralizing the LPS components and inflammatory-causing cytokines
Puerperal sepsis
Also called puerperal fever and childbirth fever Caused by Streptococcus pyogenes Transmitted to the mother during childbirth Infects the uterus and progresses to an infection of the abdominal cavity (peritonitis)
Define adjuvant.
Aluminum salts combined with many vaccines. Improve innate response, especially activation of toll-like receptors. used for surgery.
Explain the function of antibodies, and describe their structural and chemical characteristics.
An antibody is a protein that your body produces which binds to the surface of a foreign body, like a bacteria or virus, and prevents it from actively damaging your body. Antibodies, generally bind other proteins, and they will bind to specific portions of the proteins. Antibodies have a number of functions, they can directly kill the invader, or they can recruit cell to the infection. Structure: ~Proteins = Immunoglobulins (Ig) ~ Monomeric Unit composed of: - Light Chain - Heavy Chain - FC end - binds to cells - FAB end - epitope binding site
21-9 Define conjunctivitis
An inflammation of the conjunctiva; also known as red eye or pink eye -commonly caused by Haemophilus influenzae; also caused by adenoviruses can be caused by psudomonads associated with unsanitary contact lenses
Urethritis
An inflammation of the urethra
Cystitis
An inflammation of the urinary bladder Usual causative agents E. coli S. saprophyticus Symptoms Dysuria (difficult or painful urination) Pyuria (pus in urine) Diagnosis: >100 CFU/ml of potential pathogens and positive LE test Treatment: trimethoprim-sulfamethexazole
Anal gonorrhea
Anal sex transmitted.
Is the anamnestic response primary or secondary?
Anamnestic response is the renewed rapid production of an antibody on the second (or subsequent) encounter with the same antigen.
Describe the role of antibodies and natural killer cells in antibody-dependent cell-mediated cytotoxicity.
Antibodies can link target cells to natural killer cells, which then kill the targets directly by secreting toxic chemicals. killing is done by the natural killer cells, but is dependent on the presence of the antibody.
Does an antibody react with a bacterium as an antigen or as an epitope?
Antibodies react with epitopes on the antigen.
Define hapten.
Antigen is combined with carrier molecules.
Antigenic drift vs antigenic shift
Antigenic drift involves small changes to the virus Antigenic shift is abrupt, major changes to Influenza A virus, potentially causing epidemics
Arboviral encephalitis - Explain how arboviral encephalitis can be prevented.
Arboviruses Arthropod-borne viruses that belong to several families Prevention by mosquito control
What is the function of lymph nodes?
Are major sites of B, T, and other immune cells. Lymph nodes are important for the proper functioning of the immune system, acting as filters for foreign particles and cancer cells. Lymph nodes do not deal with toxicity, which is primarily dealt with by the liver and kidneys.
What type of adaptive immunity is involved when gamma globulin is injected into a person?
Artificially acquired active immunity.
Necrotizing fasciitis
Causative agent: S. pyogenes Clinical Manifestation: fever, severe pain, swelling, and redness at the wound site Treatment:Debridement and surgery are often needed to remove damaged tissue and in severe cases, amputation may be the only recourse, antibiotics Transmission:GAS reach the subcutaneous tissues through a wound or trauma to the skin surface Prevention: cleaning skin after injury
Typhoid fever
Causative agent: Salmonella enterica Clinical Manifestation: deep ulcers, bloody stools, and abdominal pain, Blood invasion leads to fever, lethargy, and delirium. Treatment: antibiotic therapy Reservoir: humans Source: water, sewage, and certain foods exposed to contaminated water. Transmission:five F's: flies, food, fingers, feces, and fomites Prevention: vaccination
Salmonellosis
Causative agent: Salmonella enterica Clinical Manifestation: fever, vomiting, nausea, diarrhea, and abdominal cramps. Treatment: fluid replacement and antibiotic therapy in severe cases Reservoir: usually animals, some humans Source: beef, poultry, and eggs Transmission: ingestion of contaminated foods Prevention: hand washing and proper food preparation large infectious does required
EHEC
Causative agent: Shiga toxin-producing E. coli Clinical Manifestation:bloody diarrhea, abdominal cramps, and a mild fever. kidney damage can be caused if severe Treatment: RBC and platelet transfusions and kidney dialysis. There is no vaccine available, antibiotics are usually not used Reservoir: Cattle Source: undercooked food or water Transmission: contaminated undercooked beef, or swimming in contaminated water Prevention: do not swim in water that cows poop in and cook food thoroughly
Shigellosis
Causative agent: Shigella sonnei and S. dysenteriae Clinical Manifestation: bloody diarrhea, fever, and abdominal cramps Treatment: antibiotic, rehydration therapy Reservoir: Humans Source: humans Transmission: fecal-oral route and person to person, contaminated food Prevention: careful hygiene small dose will cause it
Why is the lymphatic system so valuable for the working of the immune system?
Plasma leaves blood capillaries to become interstitial fluid Lymph capillaries transport interstitial fluid (lymph) to lymph vessels (lymphatics) and lymph nodes Picks up microorganisms and infectious agents Lymph nodes contain fixed macrophages, B cells, and T cells
Describe the function of natural killer cells (aka NK cells).
Police body in blood & lymph; lymphocyte that causes an infected or cancerous cell to burst.
List the causative agents, symptoms, methods of diagnosis, and treatments for pelvic inflammatory disease (PID)
Polymicrobic, usually: N. gonorrhoeae C. trachomatis Symptoms: chronic abdominal pain Treatment: doxycycline and cefoxitin
STI's
Possibility of prevention by wearing condoms. Infections are treated with antibiotics.
Gram-positive sepsis
Potent exotoxins that cause toxic shock syndrome Hospital-acquired infections Enterococcus faecium and Enterococcus faecalis Inhabit the colon Colonize wounds and the urinary tract Resistant to many antibiotics Group B streptococci (GBS) Streptococcus agalactiae Neonatal sepsis
Which of these tests is an antigen-antibody reaction: precipitation or viral hemaglutination inhibition?
Precipitation.
Which test detects soluble antigens, agglutination or precipitation?
Precipitation: agglutination reactions involve particulate antigens.
How does Mycobacterium tuberculosis avoid destruction by phagocytes?
Prevent phagosome-lysosome fusion
Syphilis
Primary stage: Chancre at site of infection Secondary stage: Skin and mucosal rashes Latent period: No symptoms Tertiary stage: Gummas on many organs Treatment: Benzathine penicillin Congenital: Neurological damage
What is opsonization?
Process of coating a microbe with a coding protein. (Bacteria are targeted for destruction by an immune cell known as a phagocyte . The process of opsonization is a means of identifying the invading particle to the phagocyte.) Leads to phagocytosis.
Define apoptosis.
Programmed cell death that typically occurs during differentiation & development.
What is another name for apoptosis, one that describes its function?
Programmed cell death.
What are Major Histocompatibility complex (MHC) molecules?
Proteins encoded by MHC genes. They recognize self to non-self genes.
Describe Rheumatic fever. Which bacteria cause this response?
Rheumatic fever is a serious complication affecting the joints and heart. It is thought to be an autoimmune response in which antibodies directed against streptococcal antigens cross-react with heart antigens.
List the signs and symptoms of sepsis, and explain the importance of infections that develop into septic shock.
S&S Fever, extreme pain or discomfort, confusion, elevated heart rate SOB Septicemia: acute illnes dut to the presence of pathogens or their toxins in the blood Sepsis: Systemic inflammatory response syndrome (SIRS) Lymphangitis: inflamed lymph vessels Severe sepsis: decreased blood pressure and dysfunction of at least one organ Septic shock: sepsis and uncontrollable blood pressure
Erysipelas (Streptococcal)
S. progenies infects dermal layer of skin → causing local tissue destruction & sepsis
Clade E
Southeast Asia
What property of the immune system suggested its use as an aid for diagnosing disease: specificity or sensitivity?
Specificity
________ coughed from the ______ respiratory tract may contain blood
Sputum coughed from the lower respiratory tract may contain blood.
E. coli 0157
Suspect Foods: -Water, vegetables, ground beef Treatment: -intravenous, rehydration, serum electrolyte monitoring Prevention: -cooking
Salmonella enterica
Suspect Foods: Eggs, poultry, vegetables Treatment: -Oral rehydration Prevention: Cooking
Yersinia enterocolitica
Suspect Foods: Meat, milk Treatment: -Oral rehydration Prevention: -Cooking
What cell causes rash from poison ivy, poison sumac, or metals?
Th1= Th(helper)
The ____________ stage of pertussis may last for months. What is the determining factor for this duration?
The Convalescence stage of pertussis may last for months. Convalescence depends on the speed at which the ciliated epithelium regenerates.
Explain the function of antibodies, and describe their structural and chemical characteristics. What is the primary advantage of the Y-shaped structure?
The Y structure=antigen binding cites (variable regions) that bind epitopes.
Benign
The body normally will respond to the tumor and encapsulate it in connective tissue
Define hemagglutination.
The clumping together of red blood cells.
What is the intent of the TORCH panel of tests?
To make sure that the babies in utero are not at risk from the mother for Toxoplasmosis Other (such as syphilis, hepatitis B, enterovirus, Epstein-Barr virus, varicella-zoster virus) Rubella Cytomegalovirus Herpes simplex virus
HIV infection
Total infect of the bodies systems, Unable to remove the virus. takes 10 years on average to kill you.
The TORCH Panel of Tests
Toxoplasmosis Other (such as syphilis, hepatitis B, enterovirus, Epstein-Barr virus, varicella-zoster virus) Rubella Cytomegalovirus Herpes simplex virus
*Compare the causative organisms, transmission, reservoirs, symptoms, and treatment of toxoplasmosis, trypansomiasis, and malaria
Toxoplasmosis: disease of blood and lymph Causative Organism: Trypansoma gondii- (a spore forming protozoan as is the malarial parasite) -cats are an essential part of life cycle of T. gondii Transmission: Cats- essential part of life cycle of T. gondii -cause no illness in a cat -microbe ndergoes its only sexual phase in the intestinal tract of the cat -Millions of oocysts are shed in he cat's feces for 7-21 days and contaminate food or water tha can be ingested by other animals Oocysts contain sporozoites that invade host cells and form trophozoites called trachyzoites -intracellular parasite reproduces rapidly -increased numbers cause rupture of the host cell and the release of more trachyzoites- resulting in strong inflammatory response -As immune system becomes increasingly effective, disease enters chronic phase in animals and humans- infected host cell develops a wall to form a tissue cyst -numerous parasites within such a cyst (in this stage called bradyzoites) reproduce very slowly if at all -persiste for years, esp in the brain -these cysts are infective when ingested by intermediate or definitive hosts. -usually aquire infection by ingesting undercooked meats containing tachyzoites or tissue cysts- although theres a possibility of contracting the disease more directly by contact w/ cat feces -if a pregnant woman accidentally ingests oocysts (contracted when changing a cat litter box), prenatal infection of the fetus may occur Reservoirs: -in cats -Cats acquire the infection mainly through eating small infected mammals, including rodents and birds, and rarely from the ingestion of infected cat feces. Symptoms: About 10-20% of people infected with toxoplasmosis will develop symptoms similar to flu or glandular fever, such as: a high temperature (fever) of 38C (100.4F) or over. aching muscles. tiredness. feeling sick. sore throat. swollen glands. Treatment: -can be treated w/ pyrimethamine in combination w/ sulfadiazine and folinic acid -this does not, however, affect the chornic bradyzoite stage and is quite toxic
In Bordetella pertussis,_______ of cell wall paralyzes ciliated cells in the respiratory tract, and impairs ____________.
Tracheal cytotoxin of cell wall paralyzes ciliated cells in the respiratory tract, and impairs mucus movement.
What is the pathogenicity of Bordetella pertussis?
Tracheal cytotoxin of cell wall paralyzes ciliated cells in the respiratory tract, and impairs mucus movement.
Describe the role of iron-binding proteins in innate immunity.
Transferrin are iron building proteins transport and store iron and deprive most pathogens of the available iron.
How is TB treated? How long does it last?
Treatment of TB: Prolonged treatment (minimun of six months) with multiple antibiotics.
How is diptheria treated? Is there a vaccine?
Treatment requires antibiotics and antitoxins. One can also get a DTaP vaccine, which uses a diphtheria toxoid for vaccination.
Upon exposure to the bacilli ____ of individuals develop _____ tuberculosis and about _____ of those will never develop an active infection. This is referred as ______________.
Upon exposure to the bacilli 30% of individuals develop primary tuberculosis About 90% of those will never develop an active infection. This is referred as latent tuberculosis .
Normal microbiota
Urinary bladder and upper urinary tract are sterile Lactobacilli are predominant in the vagina Produce H2O2 Grow on glycogen secretions
Preventing AIDS
Use of condoms Use of sterile needles (IDUs) Eliminating Female Circumcision Universal Precautions
Hantavirus Pulmonary Syndrome
Causative agent: Sin Nombre virus (SNV) Clinical Manifestation: atigue, fever, and muscle aches, if severe: headache, dizziness, difficulty breathing, and low blood pressure that can lead to respiratory failure as the lungs fill up with fluid Treatment: controlling symptoms Reservoir: deer mouse Source: saliva, urine, feces Transmission: Humans are usually infected by breathing the infectious aerosolized dry urine or feces or through direct contact with the infected rodent. Prevention: eliminating rodent nests and minimizing contact.
Rubella
Causative agent:+ssRNA virus of the Togaviridae family. Clinical Manifestation: fever with a pale-pink maculopapular rash beginning on the face and spreading to the body trunk and extremities. Treatment: none Transmission: respiratory droplets Prevention:MMR vaccine it can lead to destruction of the fetal capillaries, and blood insufficiency follows.
Measels
Causative agent:-ssRNA virus in the Paramyxoviridae family Clinical Manifestation:It begins as pink-red pimple-like spots, the rash then breaks out at the hairline, covers the face and spreads the trunk and extremities. Treatment: none Transmission:contact with respiratory droplets Prevention: MMR vaccine
Bacillus cereus food poisoning
Causative agent:Bacillus cereus Clinical Manifestation:watery diarrhea but little vomiting 6 to 15 hours after ingestion. Treatment:Fluid replacement Reservoir:Infected individual Source:Contaminated meat, poultry, vegetables, grains, rice, Transmission:Eating contaminated food
Lyme disease
Causative agent:Borrelia burgdorferi Clinical Manifestation: flu-like symptoms, fever, fatigue, rash, small flat lesion, cardiac abnormalities, chronic arthritis, swelling of joints Treatment: antibiotics Reservoir: infected rodent Source: tick that feeds on rodent Transmission: tick bites infected rodent and then bites a human Prevention:avoiding ticks and wearing protective clothing. There is a vaccine available for dogs, but there is no vaccine for humans
Chlamydial urethritis
Causative agent:Chlamydia trachomatis Clinical Manifestation:slight cervical discharge and burning during urination but not many symptoms unless severe and then it blocks fallopian tubes, ovaries, and uterus and infertillity can develope Treatment: antibiotics Reservoir:humans Source:humans Transmission:vaginal, anal, or oral sex and any sexually active individual can be infected Prevention: std screening and practicing safe sex
Clostridial food poisoning
Causative agent:Clostridium perfringens Clinical Manifestation:abdominal cramping and watery diarrhea Treatment:Rest Reservoir: Infected individual Source:Endospore that survives the cooking process in rich food
ETEC(Enterotoxagenic E. coli)
Causative agent:E. coli Clinical Manifestation: vomiting, cramps, nausea, and a low-grade fever. Watery diarrhea can last up to 3 to 7 days. Treatment: fluid replacement Reservoir: infected individual Source: contaminated food or water Transmission: fecal-oral route Prevention:careful hygiene and attention to food and water consumed when visiting endemic areas
Epstein-Barr Virus Disease
Causative agent:Epstein-Barr virus (EBV) belongs to the Herpesviridae family. Clinical Manifestation: sore throat, swollen lymph nodes, and fever-giving the disease another name, glandular fever, downey cells, and damaged b cells Treatment: none Transmission:person-to-person via saliva or saliva contaminated objects Prevention: no vaccine
Viral Gastroenteritis
Causative agent:Rotavirus or Norovirus family Caliciviridae. Clinical Manifestation:watery diarrhea, nausea, vomiting, low-grade fever, cramping, headache, and malaise Treatment:oral rehydration salt solutions fluid and electrolyte intake. Transmission: ingestion of contaminated food or water, or from contact with contaminated surfaces Prevention: vaccine washing hands and eating safe food and water
Severe Acute Respiratory Syndrome
Causative agent:SARS coronavirus (SARS-CoV Clinical Manifestation: fever, headache, and an overall feeling of discomfort, and body aches Treatment: mechanical ventillation if severe Transmission:close person-to-person contact by touching one's eyes, nose, or mouth after contact with the skin of an infected person. Prevention: good hygiene
Staphylococcal food poisoning
Causative agent:Staphylococcus aureus Clinical manifestations:abdominal cramps, nausea, vomiting, prostration, and diarrhea Treatment:Rest Reservoir:Nose of infected individual Source:Sneeze or contaminated food Transmission:Boils and abscesses or sneezing by food handler, improperly handled or stored food Prevention:proper preparations of food
Cholera
Causative agent:Vibrio cholera Clinical Manifestation: watery diarrhea that lasts a few days. severe dehydration. The blood thickens, urine production ceases, and sluggish blood flow to brain can result in shock and coma. If left untreated, death can result in less than 24 hours Treatment:restore the body's water and electrolyte balance through oral rehydration therapy, IV fluids will be administered Reservoir:intestinal tract Source: naturally found in marine water Transmission: consumption of contaminated food or water like oysters Prevention:proper water treatment measures
Bacterial Conjunctivitis
Causative agent:staphylococci, pneumococci, or streptococci Clinical Manifestation:eye redness due to dilation of the conjunctival blood vessels, eye pain, swelling, redness, and a yellow or greenish discharge. Treatment:antibiotic eye drops or ointment Transmission: sharing eye makeup or wash cloths Prevention: hand washing
glycogen secretions
Change with the menstral cycle.
What are the signs of Diptheria?
Characteristic of diphtheria is a tough, grayish pseudomembrane (dead tissue, fibrin, bacterial cells, mucus, white blood cells) on the tonsils.
Defense of the GI tract
Chemical, mechanical, and cellular defenses protect the GI tract from pathogen colonization.Antimicrobial proteins lysozyme and defensins are present in saliva, which destroy microbes. Low pH of stomach fluid kills most microbes.In the intestines, mucus coats the epithelial cells to trap microbes and to prevent contact with the epithelium. Epithelial lining sheds periodically. Antibodies are secreted in the mouth and intestines.
Identify the portals of entry for microbes into the female and male reproductive systems.
Female : Vagina Males : Urethra opening
HIV Transmission
HIV survives 6 hours outside a cell HIV survives less than 1.5 days inside a cell Infected body fluids transmit HIV via Sexual contact Breast milk Transplacental infection of fetus Blood-contaminated needles Organ transplants Artificial insemination Blood transfusion
Clades (Subtypes) of HIV
HIV-1 M (main) A to D, F to H, J, and K O (outlier) N (non M or O)
What is tested when trying to find if a donor/recipient tissue/organ is compatibility for transplantation surgeries?
HLA complex (Human Leukocyte Antigen Complex).
Herpes simplex
HSV-1: oral/ resp -90% popl infected -latent in trigeminal nerve ganglia HSV-2: sexually -latent in sacral nerve ganglia near spine *herpes gladiatorum: vesicles on skin *herpetic whitlow: fingers *herpes encephalitis: spreads to brains; acyclovir
In what way is there a connection between hemagglutination and certain viruses?
Hemagglutination: agglutination reactions involving the clumping of RBC; certain viruses can agglutinate RBC w/o an antigen-antibody reaction.
If a ____________ breaks apart, Mycobacterium tuberculosis spread throughout the body.
If a tubercle breaks apart, Mycobacterium tuberculosisspread throughout the body.
How does TB spread through the body?
If a tubercle breaks apart, bacteria spread throughout the body.
listerial meningitis
If infected macrophages cross the BBB
urban yellow fever
If that person travels to an urban area, the virus can be passed to another mosquito species, Aedes aegypti.This species then transmits the virus to another human
Which class of antibody is most likely to protect you from a common cold?
IgA
What antibody is in the mother's clostridium?
IgA antiboides, prevents the infant from getting infant gastritis.
What antibodies does the mother pass to child during birth and first 6 weeks?
IgG antibodies
Define Adaptive immunity.
Immunity or resistance to a specific pathogen.
In TB, _______________ are destroyed in AIDS patients and they can't respond to the bacterial infection.
In TB, T lymphocytes are destroyed in AIDS patients and they can't respond to the bacterial infection.
What is the etymology (origin) of the word vaccine?
In honor of Jerners' work with cowpox as a vaccine for smallpox (vacca meaning cow).
Define Toll-like receptors.
Innate immune response activated by protein receptors called Toll-like receptors (TLR) on PM of defensive cells of the host. The (TLRs) found on defensive cells (macrophages and dendritic cells) attach to various components found on the pathogen called Pathogen-associated molecular patterns (PAMPs). PAMPs Examples: LPS of gram negatives, flagellin protein, peptidoglycan of gram positive, DNA, RNA of bacteria and viruses and fungi. TLRs induce macrophages/ dendritic cells to produce cytokines that regulate the intensity and duration of immune responses.
Which defense system, innate or adaptive immunity, prevents entry of microbes into the body?
Innate immunity
Tetanus - Is the tetanus vaccine directed at the bacterium or the toxin produced by the bacterium?
It is caused by Clostridium tetani Gram positive, endospore forming, obligate anaerobe Grows in deep wounds Tetanospasmin released from dead cells blocks relaxation pathways in muscles Prevention by vaccination with tetanus toxoid (DTP) and booster (dT) Treatment with tetanus immune globulin The vaccine is a inactivated toxin that stimulates the formation of antibodies to neutralize future toxins.
Why is meningitis caused by the pathogen Listeria monocytogenes frequently associated with ingestion of refrigerated foods?
It is frequently associated with this because it is one of the few bacteria that can grow in refrigerator temperatures.
Why wouldn't a direct agglutination test work very well with viruses?
It is made to detect antibodies against relatively large cellular antigens (RBC, bacteria, fungi).
19) What produces a erythrogenic toxin that causes a pink skin rash? It is produced by some strains of Streptococcus pyogenes and damages the capillaries. It is a form of endotoxin produced by gram + bacteria. it is a product of phage conversion that inhibits protein synthesis it is produced by Neisseria meningitidis and damages the meninges
It is produced by some strains of Streptococcus pyogenes and damages the capillaries.
34: congenital zika syndrome
It is uncertain what the outcome will be in terms of neurological abnormalities for affected infants. It is suspected that infection of the fetus can lead to neurological impairments, ocular impairments, and developmental consequences on the digestive, urogenital, and cardiac systems
Why is complement given its name?
It is used in antigen-antibody reactions.
How does the natural killer cell respond if the target cell does not have MHC class I molecules on its surface?
It kills the cell by causing pores to form in it.
Tetanospasmin
It prevents the release of the neurotransmitter that is needed to inhibit muscle contraction.
Guillain-Barre syndrome (GBS)
It results from an autoimmune reaction where antibodies attack the body's own nerves. It can cause paralysis for several weeks and usually requires intensive care. Example of a sequelae.
Is vaccination an example of innate or adaptive immunity?
Its adaptive immunity because a vaccine is a killed virus or part of a virus which acts as an antigen to produce an immune response.
Experience has shown that attenuated vaccines tend to be more effective than inactivated vaccines. Why?
Live vaccines more closely mimic an actual infection. as the pathogen reproduces W/I the host cells, cellular, as well as humoral, immunity usually is included. long term effectiveness occurs b/c the attenuated viruses replicate in the body, increasing the original dose and acting as a series of secondary booster immunizations.
What are the long-range effects of Rheumatic fever?
Long-range effect: permanent scarring and distortion of the heart valves, called rheumatic heart disease
Survival With Aids Long-term nonprogressors
Mechanism not known, Beaten the 10 year mark
Differentiate plasma cell from memory cell.
Memory b cells are those cells that are not active in producing antibodies during infection, they are used when another attack of the same antigen enter the body plasma b cells are those cells that produce antibodies during the infection.
8) In developing nations, world health officials report more deaths from this disease than any other infectious disease. What is it? meningitis pneumonia influenza tuberculosis
tuberculosis
Furuncle (boil; staphylococcal)
type of abscess; localized region of pus surrounded by inflamed tissue *carbuncle: damage & inflammation of deep tissue from spreading furuncle
Monospot test
used to detect antibodies for EBV.
Malignancy
very infectious
bullae
vesicles larger than 1cm in diameter
11) This is normally a disease of infants and so we inoculate infants in our country. However, because most of us never get a booster shot, we are seeing more cases of this disease in college students and adults. What is this disease? diptheria whooping cough scarlet fever rheumatic fever
whooping cough
Gonorrhea and Syphilis
will kill you if they remain untreated.
Candidiasis common name
yeast infection
Glandular fever
ymptoms include sore throat, swollen lymph nodes, and fever-giving the disease
Differentiate agglutination from precipitation tests.
~ Agglutination involves an antigen on an INSOLUBLE cell. ~ Precipitation involves SOLUBLE antigens and antibodies.
Define antigen.
~ Antigen (Ag): A substance that causes the body to produce specific antibodies or sensitized T cells. - Antibodies (Ab) interact with epitopes or antigenic determinants.
Describe the cause and effects of fever.
~ Cause: infection from bacteria and their toxins, or viruses. Gram negative endotoxin cause phagocyte to release interleukin-1 ~ Effects: body increases rate of metabolism and shivering which raises temperature vasodilation and sweating: body temperature falls (crisis)
Identify at least one function of each of the following: cytokines, interleukins, chemokines, interferons, TNF, and hematopoietic cytokines.
~ Cytokines: Chemical messengers. ~ Interleukins: cytokins that serve as communicators b/t leukocytes (WBC) . ~ Chemokines: Induce the migration of leukocytes (WBC). ~ Interferons: cytokines that protect cells from viral infections. ~ TNF-α: Promotes inflammation. ~ Hematopoietic cytokines: Influence differentiation of blood stem cells.
Differentiate direct from indirect agglutination tests.
~ Direct is looking for the antigen directly or Igs bound to antigen (either way, there is antigen). ~ Indirect tests look for free Ig, then we have to bind it to lab antigen; more steps, but also a higher sensitivity.
What do fixed and wandering macrophages do?
~ Fixed macrophages: resident in certain tissues and organs. Ex: liver, lungs, nervous system, spleen, lymph nodes, red bone marrow. ~ Wandering macrophages: roam tissues and gather at sites of infection or inflamation.
Describe the six different types of white blood cells, and name a function for each type.
~ Granulocytes: (contain granules in cytoplasm) 1) Neutrophils-phagocytosis 2) basophils-production of histamine 3) Eoisinophils-production of toxic proteins against certain parasites; some phagocytosis ~ Aganulocytes: (lack granules) 4) monocytes- phagocytosis (precuser of macrophage) 5) dendrite cells- phagocytosis and initiation of immune response 6) lymphocytes- destroy target cells by cytolysis and apoptosis. Example: t and B cells.
Differentiate innate from adaptive immunity.
~ Innate immunity: Defenses against any pathogen. ~Adaptive immunity: Induced resistance to a specific pathogen.
Differentiate innate and adaptive immunity.
~ Innate immunity: Defenses against any pathogen. Born with it, Non-specific. ~ Adaptive immunity: Immunity, resistance to a specific pathogen. Developed after birth, very specific.
Describe at least one function of each of the following: M cells, TH cells, TC cells, Treg cells, NK cells.
~ M cells: Gateway that pathogens can pass barrier in the gastrointestinal or respiratory tract. ~ TH cells: TH cell produces cytokines that activate the B cell ~ TC cells: Target cells are self-cells carrying endogenous antigens ~ Treg cells: (CD4 and CD25 on surface) Suppress T cells against self ~ NK cells: (natural killer cells) Granular leukocytes destroy cells that don't express MHC I Kill virus-infected and tumor cells, Attack parasites
Distinguish microbial antagonism from commensalism.
~ Microbial antagonism/competitive exclusion: Normal microbiota compete with pathogens or alter the environment. ~ Commensal microbiota: One organism (microbe) benefits and the other (host) is unharmed. - May be opportunistic pathogens.
Compare the structures and function of monocytes and neutrophils.
~ Monocyte= precurser to macrophage, swelling of lymph nodes during infection. ~ Neutrophil=highly phagocytic and motile, active in intial stage of infection, destroy foriegn MO's and particles
Define phagocyte and phagocytosis.
~ Phagocyte= a cell capable of engulfing particles that are harmful to the body. ~ Phagocytosis= ingestion of particles by eukaryotic cells.
Protozoan Diseases of the Cardiovascular and Lymphatic Systems Chagas' Disease (American Trypansomiasis)
• 1. Trypanosoma cruzi causes Chagas' disease. The reservoir includes many wild animals. The vector is a reduviid, the "kissing bug."
Leishmaniasis
• 10. Leishmania spp., which are transmitted by sandflies, cause leishmaniasis. • 11. The protozoa reproduce in the liver, spleen, and kidneys. • 12. Antimony compounds are used for treatment.
Shigellosis (Bacillary Dysentery)
• 12. Shigellosis is caused by any of four species of Shigella. • 13. Symptoms include blood and mucus in stools, abdominal cramps, and fever. Infections by S. dysenteriae result in ulceration of the intestinal mucosa.
Chikungunya Fever
• 12. The chickungunya virus, which causes fever and severe joint pain, is transmitted by Aedes mosquitoes.
Babesiosis
• 13. Babesiosis is caused by the protozoan Babesia microti and is transmitted to humans by ticks.
Viral Gastroenteritis
• 13. Viral gastroenteritis is most often caused by a rotavirus or norovirus. • 14. The incubation period is 2 to 3 days; diarrhea lasts up to 1 week.
Gangrene
• 31. Soft tissue death from ischemia (loss of blood supply) is called gangrene. • 32. Microorganisms grow on nutrients released from gangrenous cells. • 33. Gangrene is especially susceptible to the growth of anaerobic bacteria such as Clostridium perfringens, the causative agent of gas gangrene. • 34. C. perfringens can invade the wall of the uterus during improperly performed abortions. • 35. Surgical removal of necrotic tissue, hyperbaric chambers, and amputation are used to treat gas gangrene.
Helicobacter Peptic Ulcer Disease
• 32. Helicobacter pylori produces ammonia, which neutralizes stomach acid; the bacteria colonize the stomach mucosa and cause peptic ulcer disease. • 33. Bismuth and several antibiotics may be useful in treating peptic ulcer disease.
Yersinia Gastroenteritis
• 34. Y. enterocolitica and Y. pseudotuberculosis are transmitted in meat and milk. • 35. Yersinia can grow at refrigeration temperatures.
Clostridium perfringens Gastroenteritis
• 36. C. perfringens causes a self-limiting gastroenteritis. • 37. Endospores survive heating and germinate when foods (usually meats) are stored at room temperature. • 38. Exotoxin produced when the bacteria grow in the intestines is responsible for the symptoms. • 39. Diagnosis is based on isolating and identifying the bacteria in stool samples.
Systemic Diseases Caused by Bites and Scratches
• 36. Pasteurella multocida, introduced by the bite of a dog or cat, can cause septicemia. • 37. Anaerobic bacteria infect deep animal bites. • 38. Cat-scratch disease is caused by Bartonella henselae. • 39. Rat-bite fever is caused by Streptobacillus moniliformis and Spirillum minus.
Clostridium difficile-Associated Diarrhea
• 40. Growth of C. difficile following antibiotic therapy can result in mild diarrhea or colitis. • 41. The condition is usually associated with health care environments and day care centers.
Vector-Transmitted Diseases
• 40. Plague is caused by Yersinia pestis. The vector is usually the rat flea (Xenopsylla cheopis). • 41. Relapsing fever is caused by Borrelia spp. and transmitted by soft ticks. • 42. Lyme disease is caused by Borrelia burgdorferi and is transmitted by a tick (Ixodes). • 43. Human ehrlichiosis and anaplasmosis are caused by Ehrlichia and Anaplasma and are transmitted by Ixodes ticks. • 44. Typhus is caused by rickettsias, obligate intracellular parasites of eukaryotic cells.
Bacillus cereus Gastroenteritis
• 42. Ingesting food contaminated with the soil saprophyte Bacillus cereus can result in diarrhea, nausea, and vomiting.
Aflatoxin Poisoning
• 5. Aflatoxin is a mycotoxin produced by Aspergillus flavus. • 6. Peanuts are the crop most often contaminated with aflatoxin.
Cyclospora Diarrheal Infection
• 5. Cyclospora cayetanensis causes diarrhea; the protozoan was first identified in 1993. • 6. It is transmitted in contaminated produce.
Hepatitis B, C, D, G
`Causative agent:(HBV) in the family Hepadnaviridae hepatitis C virus HBV and the hepatitis D virus (HDV) hepatitis G virus (HGV) Clinical Manifestation:fever, fatigue, loss of appetite, nausea and vomiting, and dark urine. fever, nausea, vomiting, and jaundice Treatment:injections with interferon alpha antiviral medications Transmission:direct contact or indirect contact with infected body fluids such as blood like a used needle primarily by blood, injection drug use, or blood transfusions Prevention:vaccination with the hepatitis B vaccine. no vaccine
Pyelonephritis
a UTI that involves one or both kidneys.
nongonococcal urethritis
a condition in which people without gonorrhea have a demonstrable infection of the urethra usually characterized by inflammation which is often accompanied by a discharge.
Postherpetic neuralgia
a condition in which the pain of shingles persists for years after the blisters have disappeared
26: enzootic
a disease endemic to a population of animals
What is the origin of HIV?
a mutation of Simian Immunodeficiency Virus or (SIV)
Sclerosing Panencephalitis
a rare brain disease characterized by a decrease in cognitive skills and loss of nervous system function.
Condylomata
a reference to the bumpy appearance of the warts.
Metasize
a spreading of cells to other tissues of the body.
Cholera toxin
disrupts the bodies ability to maintain water balance
postexposure immunization
entails five infections preceded by thorough cleansing and one dose of rabies immune globulin to provide immediate antibodies
Struct of skin
epidermis: thin outer portion, epithelial cell layers keratin: waterproofing protein coat; outer layer of epidermis dermis: inner, thick portion of skin composed mainly of CT
31: herpes keratitis
eyes can become infected through touching with a contaminated finger,
30: Hemagglutinin spikes
facilitate the attachment and entry of flu A into the epithelial host lining of the nasopharynx and tracheobronchial tree.
hydrophobia
fear of water.
TSS (staphylococcal)
fever, vomiting, shock, organ failure caused by TSS toxin 1 (TSS-1) in the bloodstream;
macules
flat, reddened lesions
types of rabies
furious rabies, is accompanied by violent symptoms as the animal becomes wide eyed, drools, and attacks anything in sight. dumb rabies, the animal is docile and lethargic, with few other symptoms.
The envelope of the HIV virus has what on it?
glycoprotein spikes termed gp120
Normal skin microbiota
gram+ pleomorphic rods (diphtheroids): *propionibacterium acnes inhabits hair follicles; anaerobic → produce acids that maintain low skin pH *corynebacterium xeorosis occupy the skin surface; aerobic yeast: malassezia furfur; cause dandruff
Toxic megacolon
grossly dilated bowel
chickenpox (varicella)
herpesvirus varicella-zoster (human herpes 3) transmit: resp causes: pus-filled vesicles Reye's syndrome: severe complications of chickenpox; vomitting & brain dysfunction → aspirin inc risk virus becomes latent in central nerve ganglia prevented by live attenuated vaccine **breakthrough varicella: can occur if previously vaccinated
moisture in perspiration encourages microbial growth. what perspiration factors discourage growth?
high SALT content
mucous membrane
line body cavities open to exterior tightly packed epithelial cells attached to extracellular matrix → cells secrete mucus, some have cilia often acidic memb of eyes washed by lysozyme in tears often folded to max SA
28: Male and Female primary and accessory organs
male: The primary sex organs are the testes, which produce sperm cells and sex hormones such as testosterone. The accessory sex organs include the epididymis, which stores sperm until they are mature and motile. Other accessory sex organs include the vas deferens, seminal vesicles, and prostate gland, which function to produce and transport semen. Finally, the external organs are the scrotum and penis. female: primary sex organs (ovaries), and accessory sex organs, which include the fallopian tubes, uterus, cervix, vagina, and vulva.
Characteristics of the urinary tract
removes waste products from the blood and helps maintain homeostasisThe organs of the urinary system include two kidneys, two ureters, a urinary bladder, and a urethra. The kidney's filer waste products from the bloodstream and convert the filtrate to urine. The ureters, bladder, and urethra are collectively known as the urinary tract.
Reticulate body
replicating, intracellular, non infectious
23: Digestive System
represents another major portal of entry for pathogens. It is composed of the organs that ingest the food, transport and digest the food into smaller useable components, absorb nutrients into the bloodstream, and expel waste products from the body.
Normal skin microbiota
resistant to drying & high salt conc large #s of G+ cocci (staphylococci, micrococci) areas w/ moisture have higher populations *metabolize sweat & contribute to body odor → probiotic, ammonia oxidizing spray
Measles
resp cold-like symptoms, macular rash koplik's spots
Viral diseases
resp route → systemic problems in children & developing fetuses
HIV is what type of virus?
retrovirus
There are some anti-viral HIV drugs out there what are they?
reverse transcriptase inhibitors protease inhibitors cell entry inhibitors integrate inhibitors
4) Which of the following diseases appears to be the result of an autoimmune response? primary atypical pneumonia rheumatic fever diphtheria otitis media
rheumatic fever
What is highly active antiretroviral therapy?
several drugs that are used in a combination to combat infection
What does the Latent infection do?
shelters virus from the immune system
Acne
skin cells shed in hair follicles & combine w/ sebum → blockage affected by hormones Types: 1. comedonal (mild): easily treated w/ topical 2. inflammatory (moderate): Propionibacterium acnes - metabolize sebum; FA produce inflammatory responce; treat: benzoyl peroxide 3. nodular cystic (severe): inflamed lesions w/ pus deep in skin
exanthem
skin rash arising from a disease
Vesicles
small (1cm) fluid filled lesions
neuraminidase spikes
ssist in the release of the newly replicated virions from the host cells.
What would be a good vaccine against AIDS?
subunit vaccines
Seroconversion
takes up to 3 months HIV antigens detected by Western blotting
What changes in the vaginal bacterial microbiota tend also to favor the growth of the yeast Candida albicans?
the Ph changes after the monthly cycle
Tumor
the cluster of cells yields a clone of abnormal cells
Cancer
the disease caused by an uncontrolled division of abnormal cells in a part of the body
What is the association between estrogens and the microbiota of the vagina?
the estrogen starts the menses and the microbiota changes and clears out the vagina and uterus sort of like a reset button. or a giant Czechoslovakian maid named Olga who brutally raises the ph in the ueterus
Attachment to the target cell depends on what?
the glycoprotein spike needs to combine with a CD4+ receptor
Dengue hemorrhagic fever
the immune system reacts to the memory of the first infection, allowing the new one to replicate unchallenged.
What happens during Phase 1 Asymptomatic?
the initial HIV virus increases then declines when the number of CD4+ T cell declines then rebounds
What does the gp120 represent about the glycoprotein spikes?
the molecular weight of the glycoprotein at 120,000
What happens in Phase 2 of HIV?
the number of CD4+ cells steadily decline
dysentery
the passage of blood and mucus in the feces
18) The appearance of a strain of Mycobacterium tuberculosis designated MDR-TB has necessitated short term drug treatment. complete bed rest of the patient. the use of three or more drugs for 6 months. T lymphocyte transfusions.
the use of three or more drugs for 6 months.
Syncytia
the virus infects ciliated epithelial cells of the airways, they tend to fuse together, forming giant multinucleate cells
How is AIDS diagnosed?
there are 200 cells/ul or less CD4+ T-cells
arbovirus
they are arthropod-borne viruses, meaning the virus is transmitted by arthropods, primarily through bites of infected ticks and mosquitos.
How do dendritic cells spread HIV?
they pick up the virus and carry it to the lymphoid organs and when it is there it contacts cells of the immune system and stimulates a strong immune response
Toxoplasmosis
transmitted by cat feces causes spontaneous abortion
Neonatal herpes
transmitted by infected mothers to newborns during childbirth
What does HIV stand for?
Human Immunodeficiency Virus
How does Streptococcus pneumoniae avoid destruction by phagocytes?
Inhibit adherence: M protein, capsules
What is interferon?
It is a proteins made by virus infected cells to stop spread of infection. (nosey neighbors)
Shigella spp.
Suspect Foods: -Water, environmental fecalcontamination Treatment: -Quinolones Prevention: Disinfection
Necrotizing fasciitis (Streptococcal)
"flesh-eating" disease exotoxin A produced by S. progenies acts as superantigen Streptococcal TSS (similar to staphyloC TSS)
Describe the role of antimicrobial peptides in innate immunity.
(AMP's) inhibit cell wall synthesis; from pores in plasma membranes, resulting in lysis, and destroy DNA and RNA. AMP's are produced by nearly all plants and animals and bacterial resistance to AMP's has not yet been seen.
Compare and contrast direct and indirect fluorescent-tests.
*Fluorescent antibody techniques use antibodies labeled with fluorescent dyes. ~ Direct fluorescent antibody test -used to identify specific microorganisms ~ Indirect -used to demonstrate the presence of antibody in serum
Pseudomonas aeruginosa
*G- aerobic rod *pyocyanin produces blue-green pus & smells like grapes *produces exo & endotoxins *grows in biofilms *Pseudomonas dermatitis: self-limiting rash acquired in swimming pools *otitis externa: "swimmers ear" *opportunistic in burn patients *resistant to many antibiotics
Describe the role of the skin and mucous membranes in innate immunity.
- Epithelium is the thin outer covering of mucous membranes. 1) Is tightly packed to prevent entry of pathogens. 2) Is not keratinized and it continually sheds, carrying away pathogens. 3) Produces mucus which traps pathogens. 4) It can produce chemicals like lysozyme (eyes and saliva) and other chemicals that create an acidic pH.
Compare and contrast the actions of IFN-α and IFN-β with IFN-γ.
- IFN-α and IFN-β: cause cells to produce antiviral proteins that inhibit viral replication - IFN-γ: causes neutrophils and macrophages to phagocytize bacteria.
*What are the symptoms of brucellosis? Why do the organisms survive so well in the host?
-Brucella bacteria -easily become airborne during lab handling- very dangerous to handle -potential agent of bioterrorism -most cases of brucellosis are caised by B. melitensis -inncubation period 1-3 weks -symptoms have a wide spectrum, depending on stage of disease and organs affected -include fever (often rising and falling- given disease an alternative name of undulant fever), malaise, night sweats, and muscle aches -bacteria evade host's defenses -the organisms are especially adept at evading phagocytic cells
Which diseases of the GI tract can be acquired by swimming in a pool or lake? -Why are these diseases not likely to be acquired while swimming in the ocean?
-Cryptosporidiosis -Otitis externa -Giardia -Pseudomonas dermatitis -Legionella -These diseases are not likely to be acquired while swimming in the ocean because of the salt, which dehydrates cells, and prevents them from being able to produce (slowing their growth) or killing them. Other bacteria are tolerant to salt, and others have become resistant to it
*How does Helicobacter pylori survive the high acidity of the stomach? Outline the progression of peptic ulcer disease.
-H. pylori neutralizes the gastric acid, hydrochloric acid (HCl) -they produce large amounts of the enzyme UREASE -Urea- which is normally secreted into the stomach, is Converted into CO2 and AMMONIA. -The ammonia neutralizes the gastric HCL. Progression of Peptic Ulcer Disease: --stomach mucosa- contains cells that secrete gastric juice containing proteolytic enzymes and HCL that activates these enzymes -other specialized cells, produce a layer of mucus that protects stomach itself from digestion -if this defense is disrupted, an inflammation of the stomach (gastritis) Results -inflammation can then progress to an ulcerated area -through an interesting adaptation, H. pylori can grow in the highly acidic env of the stomach -produces large amounts of especially efficient urease- an enzyme that converts urea to the alkaline compound ammonia -results in locally high pH in the area of growth
*How are anthrax infections initiated? What are the 3 types of anthrax infections?
-Infections are initiated by ENDOSPORES -once introduced into the body- they are taken up by macrophages where they germinate into vegetative cells -these are not killed, but multiply- KILLING the macrophage eventually -released bacteria then enter the bloodstream, replicate rapidly, and secrete toxins -Bacillus anthracis -anthrax affects humans in 3 forms: cutaneous anthrax, gastrointestinal anthrax, and inhalation (pulmonary ) anthrax Cutaneous Anthrax: -results from contact w/ material containing anthrax endospores -90% of naturally occurring cases of anthrax in humans are cutaneous -endospore enters minor skin lesion -papule appears and eventually vehicles, which rupture and form depressed, ulcerated area that is covered by a black eschar (scab) -in most cases- pathogen does not enter the bloodstream and other symptoms are limited to a low-grade fever and malaise -if bacteria enter bloodstream, mortality without antibiotic treatment can reach 20%; with antibiotic therapy- mortality is less than 1% Gastrointestinal Anthrax- rare -caused by ingestion of undercooked food containing anthrax endospores -symptoms: nausea, abdominal pain, bloody diarrhea -ulcerative lesions occur in GI tract ranging from mouth and throat to mainly the intestines -mortality is usually more than 50% Inhalation (pulmonary) anthrax- most dangerous -endospores inhaled into lungs have a high probability of entering bloodstream -symptoms of fist few days of infection- not esp alarming: mild fever, coughing, some chest pain -disease can be arrested at this stage by antibiotics, but unless suspicion of anthrax is high, they are unlikely to be administered. -as bacteria enter bloodstream and proliferate, the illness progresses in 2 or 3 days into septic shock that usually kills the patient within 24-36 hrs -mortality rate approaches 100%
21-2 Provide examples of normal skin microbiota, and state the general locations and ecological roles of its members î
-Resistant to drying and high salt concentration. -Large numbers of gram-positive cocci; Staphylococci and Micrococci -Areas with moisture have higher populations; Metabolize sweat and contribute to body odor Gram positive pleomorphic rods (diphtheroids) -Propionibacterium acnes inhabits hair follicles; anaerobic; lives on sebum; produces acids that maintain low skin pH -Corynebacterium Xeroxes occupies the skin ; aerobic Yeast -Malassezia furfur; causes dandruff -Dandruff shampoos contain antibiotic against this yeast
*How does puerperal sepsis caused by Streptococcus pyogenes occur? What preventative measures have made this disease much less common?
-also called puerperal fever and childbirth fever- a nosocomial infection -begins as infection of the uterus as a result of childbirth or abortion -Streptococcus pyogenes- a group A beta-hemolytic streptococcus- most frequent cause -progresses from infection of uterus to an infection of abdominal cavity (peritonitis) and in many cases to sepsis -earlier- it was demonstrated that disease was transmitted by hands and instruments of the attending midwives or physicians and that disinfecting the hands and instruments could prevent such transmission -antibiotics- esp penicillin and modern hygienic particles have now made S. pyogenes puerperal sepsis an uncommon complication of childbirth
*Describe how the cardiovascular and lymphatic systems can spread disease in the body or eliminate disease
-blood and lymph distribute nutrients and oxygen to body tissues and carry away wastes -vehicles for the spread of pathogens that enter their circulation when an inset bite, needle, or wound penetrates the skin -lymph capillaries- very permeable—readily pick up microbes or their products
*Describe the properties of Clostridium spp. and Bacillus spp. that give these organisms advantages in surviving in the digestive tract.
-both are endospore forming -endospores survive most routine heatings -spores germinate as food cools
*List the major components of the cardiovascular and lymphatic systems. -What is the relationship between these 2 systems?
-cardiovascular system: heart, blood, blood vessels -lymphatic system: lymph, lymph vessels, lymph nodes, lymphoid organs such as tonsils, appendix, spleen, thymus. -blood and lymph distribute nutrients and oxygen to body tissues and carry away wastes -Many of body's innate defensive systems are found in blood and lymph -circulating phagocytic cells- esp important. Also in fixed locations such as lymph nodes and spleen -blood is an imp part of our adaptive immune system: antibodies and specialized cells circulate to intercept pathogens introduced into the blood. -function of cardiovascular system: to circulate blood through body's tissues to deliver substances to cells and remove other substances from them -Blood- mixture of formed elements and blood plasma. -Lymphatic system- essential part of circulation of blood -some plasma filters out of blood capillaries into spaces between tissue cells called interstitial spaces -circulating fluid-interstitial fluid -lymph capillaries- lymph vessels that surround tissue cells -interstitial fluid moves around the tissue cells- its picked up by lymph capillaries- fluid is then called lymph -lymph capillaries- very permeable—readily pick up microbes or their products -from lymph capillaries - lymph is transferred into lymphatics (contain valves that keep lymph moving to heart) -all lymph is returned to blood before blood enters heart.
*Describe the epidemiology and etiology of Lyme disease
-caused by Borrelia burgdorferi -tickborne disease -in US- most prevalent on Atlantic coast -a spirochetal infection, which is transmitted by the bite of infected Ixodes ricinus complex ticks. -caused primarily by Borrelia burgdorferi in the United States, and primarily Borrelia afzelii, Borrelia burgdorferi, and Borrelia garinii in Europe and Asia -first symptoms of the disease: usually a rash that appears at bite site -red area that clears in the center as it expands to a final dimeter of about 15cm -distinctive rash occurs in about 75% of cases -Flulike symptoms appear in a couple of weeks as the rash fades -Antibiotics taken during this interval are very effective in limiting the disease
*How are bubonic and pneumonic plague transmitted?
-comes from one of its characteristics: the darkblue areas of skin caused by hemorrhages -disease caused by gram-negative, rod-shaped bacterium, Yersinia pestis -normally a disease of rats, plague is transmitted from one rat to another by the rat flea, Xenopylla cheopis -if host dies, flea seeks a replacement host, which may be another rodent, or a human -can jump about 3.5inches -plague-infected flea is hungry for a meal because the growth of the bacterium forms a biofilm that blocks the flea's digestive tract, and the blood the flea ingests is quickly regurgitated -an arthropod vector- not always necessary for plague transmission -contact from skinning of infected animals -scratches, bites, and licks by domestic cats, -and similar incidents have caused infection -From flea bite, bacteria enters human's bloodstream and proliferates in lymph and blood -one factor of virulence of plague bacterium: its ability o survive and proliferate inside phagocytic cells rather than being destroyed by them -increased number of highly virulent organisms eventually emerges and an overwhelming infection results -lymph nodes in groin and armpit become enlarged -fever develops as body's defenses react to infection -swellings called buboes- account for name bubonic plague -dangerous condition called septicemic plague- arises when bacteria enter the blood and proliferate, causing septic shock -eventually, the blood carries bacteria to the lungs and a form of the disease is called pneumonic plague results -mortality rate of this type of plague- nearly 100%
*List the anatomical structures of the digestive system that are in contact with food.
-gastrointestinal tract or alimentary canal- mainly MOUTH, PHARYNX (throat), ESOPHAGUS , STOMACH, SMALL and LARGE INTESTINES -also includes accessory structures- TEETH and TONGUES -other accessory structures- salivary glands, liver, gallbladder, pancreas- lie outside GI tract- produce secretions that are conveyed by ducts into it
*Outline the sequence of events of staphylococcal food poisoning.
1. Food containing protein is cooked (bacteria usually killed) 2. Then food is contaminated by worker with staphylococci on hands (competing bacteria have been eliminated). 3. Food is left at room temperature. Organisms incubate in food (temperature abuse) long enough to form and release toxins. (Reheating will eliminate staphylococci but not the toxins). 4. Food containing toxins is eaten 5. In 1-6 hrs, staphylococcal intoxication occurs -Staphylococcal Enterotoxicosis -intoxication caused by ingesting an enterotoxin produced by S. aureus -staph-resistant to env stresses -high resistance to heat -resistance to high osmotic pressure- helps them grow in foods in which osmotic pressure of salts inhibits growth of competitors (cured ham) -S. aureus- inhabits nasal passages, from which it contaminates hands -frequent cause of skin lesions on hands -if microbes are allowed to incubate in food- temperature abuse occurs- they reproduce and release enterotoxin into the food -->staph intoxication
*Describe the signs and symptoms of gangrene and the etiology of this disease.
-if a wound causes blood supply to be interrupted, a condition known as ischemia, the wound becomes anaerobic. -Ischemia leads to necrosis- death of the tissue -death of soft tissue resulting from loss of blood supply is called gangrene -can also occur as a complication of diabetes -Clostridium perfringens -Once ischemia and the subsequent necrosis caused by impaired blood supply have developed, gas gangrene can develop -esp in muscle tissue -as C. perfringens microbes grow, they ferment carbs in the tissue and produce gases (CO2 and hydrogen) that swell the tissue -bacteria produce toxins that move along muscle bundles, killing cells and producing necrotic tissue that is favorable for further growth -eventually, these toxins and bacteria enter the bloodstream and cause systemic illness -enzymes produced by bacteria degrade collagen and proteinaceous tissue- facilitating spread of disease -fatal without treatment -surgical removal of necrotic tissue and amputation- most common medical treatments for gas gangrene -blac, necroting tissue- resulting from poor circulation or injury.
*Describe the physiological manifestation of septic shock
-if bodys defenses do not quickly control infection and the resulting SIRS- results are progressive and frequently fatal -first stage of progression: sepsis -there is evidence of infection and inflammatory response by the body caused by release and circulation of cytokines -most obvious signs and symptoms: fever, chills, accelerated breathing and heart rate -when sepsis results in a drop in B.P. (shock) and dysfunction of at least one organ- severe sepsis -organs begin to fail- mortality rate becomes very high -final stage- B.P. can no longer be controlled by additional fluids- septic shock -septic shock- most likely caused by gram-negative bacteria -cell walls- LPS- contain endotoxins released upon lysis of cell -endotoxins- cause drop in B.P with associated signs and symptoms -Septic Shock- often called by the alternative names gram-negative sepsis or endotoxic shock -treatment: involves attempts to neutralize the LPS components and inflammation-causing cytokines
Infection vs intoxication
-infection- occurs when pathogen enters the GI tract and multiplies -some pathogens cause disease by forming TOXINS that affect GI tract -intoxication- caused by the ingestion of such a performed toxin
*What 2 microorganisms are most likely to cause septicemia? Why can antibiotic treatment exacerbate septicemia?
-septic shock- most likely caused by gram-negative bacteria -cell walls- LPS- contain endotoxins released upon lysis of cell -endotoxins- cause drop in B.P with associated signs and symptoms -Septic Shock- often called by the alternative names gram-negative sepsis or endotoxic shock -antibiotic treatments that might arrest it then are frequently not administered -progression to lethal stages is rapid and generally impossible to treat effectively -administering antibiotics then may even aggravate the conditions by causing the lysis of large # of bacteria that release more endotoxins.
*Describe how fungi can cause diseases of the digestive tract.
-some fungi produce toxins called MYCOTOXINS -when ingested- toxins cause blood diseases, nervous system disorders, kidney damage, liver damage, and even cancer example: Ergot Poisoning: -some mycotoxins produced by Claviceps purpurea -cause ergot poisoning- ergotism -result from ingestion of rye or other cereal grains contaminated w/ fungus -toxin- restrics blood flow in limbs--> gangrene
*How are normal microbiota restricted to the mouth and large intestine? What types of microorganisms are found mostly in the large intestine?
-stomach and small intestine- few microbes b/c of hydrochloric acid and rapid movement of food through small intestine food through small intestine -mouth has large microbial populations -large intestine- has ENORMOUS microbial populations -most of these bacteria assist in the enzymatic breakdown of foods- esp polysaccharides that would otherwise be indigestible -some synthesize useful vitamins -population of large intestine is composed mostly of ANAEROBES and FACULTATIVE ANAEROBES
*Describe the disease rheumatic fever
-streptococcal infections (such as those caused by S. pyogenes) sometimes leads to rheumatic fever- generally considered an autoimmune complication -follows episode of streptococcal sore throat -disease is usually first expressed as short period of arthritis and fever -Subcutaneous nodules at joints accompany this stage -in half of ppl affected, inflammation of heart (prob from a misdirected immune reaction against streptococcal M protein) damages the valves -reinfection with streptococci- renews immune attack -damage to heart valves may be serious enough to result in failure and death -characteristic subcutaneous nodules appear at the joints. -ppl who have had an episode of rheumatic fever are at risk of renewed immunological damage with repeated streptococcal sore throats -the bacteria have remained sensitive to penicillin
*What is endocarditis? What medical procedure can result in endocarditis?
-wall of heart consists of 3 layers: -endocardium-inner layer- lines heart muscle itself and covers the valves. -endocarditis-inflammation of the endocardium -one type of bacterial endocarditis-subacute bacterial endocarditis- develops slowly; fever, general weakness, heart murmur -usually caused by alpha-hemolytic streptococci (such as are common in oral cavity, although enterococci or staphylococci are often involved) -condition- prob arises from a focus of infection elsewhere in the body- teeth or tonsils -microbes are released by TOOTH EXTRACTIONS or TONSILLLECTOMIES, enter blood, and find way to the heart -a more exotic source of infections that have led to cases of endocarditis has been BODY PIERCINGS (esp of nose, tongue, and even nipples) -in ppl whose heart valves are abnormal (b/c of either congenital heart defect such as diseases as rheumatic fever and syphilis), the bacteria lodge in the pre-existing lesions. -one type of bacterial endocarditis-subacute bacterial endocarditis- develops slowly; fever, general weakness, heart murmur -usually caused by alpha-hemolytic streptococci (such as are common in oral cavity, although enterococci or staphylococci are often involved) -condition- prob arises from a focus of infection elsewhere in the body- teeth or tonsils -microbes are released by tooth extractions or tonsillectomies, enter blood, and find way to the heart -a more exotic source of infections that have led to cases of endocarditis has been body piercing (esp of nose, tongue, and even nipples)
Complications of influenza
1. Guillain-Bare syndrome occurs when the body mistargets the infection and attacks nerve cells, resulting in muscle weakness and sometimes paralysis. 2. Reye syndrome occurs mostly in young people after given aspirin to treat fever or pain associated with the infection.
HIV Phase 3
AIDS indicator conditions, Considered Aids takes on average 8 years.
List three pathogens that are transmitted by animal bites and scratches. - Bartonella henselae, the pathogen of cat-scratch disease, is capable of growth in what insect?
1% of ER visits Dogs make up 80% of reported bites; cats about 10% Cat bites have higher infection rates Pasteurella multocida Gram-negative rod; causes sepsis Staphylococcus, Streptococcus, Corynebacterium *Cat fleas
Describe four outcomes of an antigen-antibody reaction.
1) Agglutination: Causes antigens to clump together - more easily digested by phagocytes e.g. 2) Opsonization: (from greek to cater) Coat bacteria with antibodies that enhance ingestion and lysis by phagocytes 3) Neutralization: Block viruses from attaching to host receptors - can neutralize toxins in a similar manner 4) Activation of Complement system: IgG and IgM bind and allow C1 to bind and start complement cascade. Lysis of the microbe attracts phagocytes to the site of infection
What is the function of Tc (cytotoxic) that become CTL (cytotoxic T lymphocytes)?
1) Bind to MHC I on target cells (example: self cells infected with viruses, tumor cells, foreign tissues) 2) Produce perforins- cytolysis 3) Produces granzymes- apoptosis 4) Phagocytes appear that prevent spread of infection.
What is the function of Ts/r (suppressor/regulatory)?
1) Combat autoimmune by suppressing T-cells that escaped thymic selection 2) Reaction against intestinal bacteria 3) Protection of fetus during pregnancy
Identify six mechanisms of avoiding destruction by phagocytosis.
1) Inhibit adherence: M protein, capsules 2) Kill phagocytes: Leukocidins 3) Lyse phagocytes: Membrane attack complex 4) Escape phagosome 5) Prevent phagosome -lysosome fusion 6) Survive in phagolysosome
What are the 5 different first line of defense of physical barriers?
1) Intact Skin 2) Mucous Membranes 3) Lacrimal Apparatus 4) Saliva 5) Flow of Urine
Contrast the four types of adaptive immunity.
1) Naturally aquiring active immunity: resulting from infection 2) Naturally aquired passive immunity: transplacental or via colostrum 3) Artifically aquired active immunity: injection of Ag (vaccination) 4) Artificaially aquired passive immunity: injection of Ab
What causes the redness, swelling, and pain associated with inflammation?
1) Redness: vasodilation 2) Pain: increase permeabillity and causes edema. 3) Swelling: plasma proteins and leukocytes
What are the 4 different first line of defense of chemical barriers?
1) Sebum 2) Perspiration 3) Lysozyme 4) pH of gastric juices
What is the function of Th2?
1) Stimulate B-cells to make IgE 2) prevent/defend against parasitic infections by stimulating eosinohils
What are the 2 types of specific immune response?
1) T-cell response 2) B-cell response
What is the function of Th1?
1) delayed hypersensitivity 2) mediate T- independent B-cell response to mak IgA, IgD, IgG. 3) activate macrophages 4) activate complement (example: opsonization--> inflammation--> phagocytosis--> cytolysis)
List the stages of inflammation.
1) redness 2) swelling 3) heat 4) pain 5) loss of function (a.) damage to otherwise healthy tissue- in this case skin (b.)vasodilation and increased permeability of blood vessels (c.) phagocyte migration and phagocytosis of bacteria and cellular debris by macrophages and neutrophils. Macrophages develop from monocytes (d.)the repair of damage tissue
Characteristics of organisms that are sexually transmitted
1. Persist in an infective form until that person has sexual intercourse.2. Hide themselves from recognition and elimination by the immune system3. Be ready to be transmitted when the infected individual has sexual intercourse.
Stages of lyme disease
1. The early localized stage involves a fever, fatigue, and a slowly expanding red rash at the site of the tick bite (erythema migrans (EM)). It begins as a small flat or raised lesion, the rash increases in diameter in a circular pattern over a period of weeks, termed a bulls-eye rash. The bite site does not itch. Fever, aches and pains, and flu-like symptoms usually accompany the rash. 2. Left untreated, an early disseminated stage begins weeks to months later with the spread of the pathogen to the skin, heart, nervous system, and joints. Multiple smaller EMs develop, invasion of the nervous system can lead to meningitis, facial palsy, and peripheral nerve disorders. Cardiac abnormalities can occur, as well as joint and muscle pain. 3. If still left untreated, late stage occurs within months to years later. About 10% of patients develop chronic arthritis with swelling in the large joints, such as the knee. Overall damage to the body can be substantial.
Stages of syphilis
1.Primary syphilisIt is characterized by a lesion, called a chancre, which is a painless circular, purplish ulcer with a small, raised margin with hard edges. 2. Secondary syphilis: Symptoms include fever and a flu-like illness as well as swollen lymph nodes. The skin rash that develops appears as reddish-brown spots on the palms, face, and trunk. 3. Tertiary Syphilis: The hallmark of the tertiary stage is the gumma, a soft, painless, gummy, noninfectious granular lesion. In the CV system, the gumma causes the blood vessels to weaken. In the spinal cord and meninges, gummas can lead to degeneration of the tissues and paralysis. In the brain, they can alter the patient's personality and judgment.
How many viruses per milliliter does semen contain?
10-50 viruses
How many viruses per milliliter does blood contain?
1000-100,000 infective viruses
What is acute glomerulonephritis?
Acute glomerulonephritis is a rare inflammatory disease.
Staph. epidermidis
90% of normal skin microbiota healthcare-assoc pathogen biofilms on catheters coagulase(-)
About _____ will contract clinical TB.
About 10% will contract clinical TB.
What does AIDS stand for?
Acquired Immunodeficiency Syndrome
Impetigo (staphylococcal)
crusting (nnnbullous) sores spread by auto inoculation (also bullous form)
Describe clonal selection.
Activates a small number of lymphocytes with complementary receptors, those lymphocytes multiply into effector cells (primary immune response) which fight specific antigen, and memory cells build long term immunity (secondary immune response)
Group A streptococci (GAS): S. pyogenes
8 immunological types produce virulence factors *streptolysins: lyse RBCs *M proteins: ext to cell wall; allow adherence & immune system avoidance *hyaluronidase: dissolves CT *streptokinases: dissolves blood clots
Infection is indicated by
>10,000 bacteria/ml 100 coliforms/ml Positive urine leukocyte esterase (LE) test
24-6 List the causative agent, symptoms, prevention, preferred treatment, and laboratory identification tests for pertussis and tuberculosis. 24-7 Compare and contrast the seven bacterial pneumonias discussed in this chapter. 24-8 List the etiology, method of transmission, and symptoms of melioidosis.
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A patient presents with fever and a red, sore throat. Later, a grayish membrane appears in the throat. Gram-positive rods were cultured from the membrane. Can you identify infections that could cause these symptoms?
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Describe how microorganisms are prevented from entering the respiratory system. 24-2 Characterize the normal microbiota of the upper and lower respiratory systems.
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Differentiate pharyngitis, laryngitis, tonsillitis, sinusitis, and epiglottitis. 24-4 List the causative agent, symptoms, prevention, preferred treatment, and laboratory identification tests for streptococcal pharyngitis, scarlet fever, diphtheria, cutaneous diphtheria, and otitis media.
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How do these bacteria, by growing on these particular body cells, cause the disease pertussis?
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What is the function of hairs in the nasal passages? 24-1 Normally, the lower respiratory tract is nearly sterile. What is the primary mechanism responsible? 24-2
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Which one of the following is most likely to be associated with a headache: pharyngitis, laryngitis, sinusitis, or epiglottitis? 24-3 Among streptococcal pharyngitis, scarlet fever, or diphtheria, which two diseases are usually caused by the same genus of bacteria? 24-4
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Define antigen-presenting cell.
A cell that can "present" antigen in a form that T cells can recognize it.
What is Phase 3 in HIV?
AIDS
Describe how a human can produce different antibodies.
A foreign substance that invades the body is called an antigen. When an antigen is detected, several types of cells work together to recognize and respond to it. These cells trigger the B lymphocytes to produce antibodies. Antibodies and their responding antigens fit together like a key and a lock. Once the B lymphocytes have produced antibodies, these antibodies continue to exist in a person's body. If the same antigen is presented to the immune system again, the antibodies are already there to do their job. This principle forms the basis of immunizations. The immunization introduces the body to the antigen in a way that does not make a person sick, but it does allow the body to produce antibodies that will then protect that person from future attack.
ELISA test.
A group of serological tests that use enzyme reactions as indicators. (direct: detects antigens; indirect: detects antibodies)
What is complement?
A group of serum proteins involved in phagocytosis and lysis of bacteria. the complement system is a defensive system consisting of over 30 proteins produced by the liver and found circulating in blood serum and within tissues throughout the body.
What animal does the infecting tick feed on just before it transmits Lyme disease to a human?
A living animal before it affects humans
27: Vector
A living organism such as an arthropod that transmits disease agents
What vaccines are being developed against TB?
A number of new vaccines are in the experimental pipeline for TB: subunits, molecules of DNA, and attenuated strains of mycobacteria.
A paroxysm is a __________ and is characteristic of _________.
A paroxysm is a rapid-fire coughand is characteristic of pertussis.
What does it mean if one tests positive for TB?
A positive reaction means current infection or recent immunization, previous tuberculin test, or past exposure to M. tuberculosis.
Define vaccine.
A preparation of antigenic material (could be whole organism, part of the organism, or a toxin from the organism) used to induce immunity against pathogenic organisms.
What is a pseuomembrane? What bacteria causes this to form?
A pseudomembrane consists of dead tissue, fibrin, bacterial cells, mucus, white blood cells and if formed by C. diptheriae.
Dengue shock syndrome
A rash from skin hemorrhages appears on the face and extremities, and severe vomiting and shock ensue (dengue shock syndrome) as blood pressure decreases dramatically.
What is a serotype?
A serotype is a variation within a species. Strains of strptococci with different antigens are called serotypes, serovars, or biovars.
Explain why vaccination works. Vaccination is often the only feasible way to control most viral diseases; why is this?
A vaccination works because it mimics the disease w/out illness. Vaccines help create antibodies for the pathogen ahead of time, that way when you get sick in the future, you can fight it off quickly and efficiently. Once viruses is contracted they cannot often be effectively treated once they are contracted.
Lesson Notes
As we mentioned in Unit 12, cryptosporidiosis has been implicated in several outbreaks of gastrointestinal infections in different regions within Canada. In the first of these, individuals in a town in Ontario developed gastroenteritis after eating fresh berries originally grown in South America. In this case, water containing sewage materials was used to irrigate the crops. In the second of these outbreaks, individuals in a resort town in Canada succumbed to the same infection. However, it has been proposed that the source of the infection was contaminated lake water. Individuals swimming in the lake or drinking water drawn from the lake would both have been readily infected with these organisms.
What is Phase 1 in HIV?
Asymptomatic
HIV Phase 1
Asymptomatic or chronic lymphadenopathy, Immediate spike of virus and white blood cells. Swollen lymph nodes tenderness. host is infectious.Positive
Describe the epidemiologies of Rheumatic fever
Autoimmune complication of S. pyogenes infections Inflammation of the heart valves Immune reaction against streptococcal M protein Subcutaneous nodules at the joints Sydenham's chorea Purposeless, involuntary movements
How do people prevent AIDS?
Avoid sexual promiscuity
What cell response is effective against freely circulating antigens, like viruses and bacteria?
B-cell response
Encephalitis is an inflammation of what organ or organ structure?
Brain
Bacteria, viruses, and fungi cause _____, ________, and ________ in the lower respiratory system.
Bronchitis Bronchiolitis Pneumonia
BCG is a live culture of ____________ used against TB.
BCG is a live culture of avirulent M. bovis used against TB.
What is the BCG vaccine?
BCG is a live culture of avirulent M. bovis used against TB. Available since 1920. Not widely used in U.S. Diagnosis Tuberculin skin test (Mantoux test) can be used for early detection of TB exposure Positive reaction means current infection or recent immunization, previous tuberculin test, or past exposure to M. tuberculosis Followed by X-ray or CT exam, acid-fast staining of sputum, culturing of bacteria
What are examples of microbial antigens?
Bacteria, Fungi, protozoa, helminth parasites, and food.
Lesson Notes
Because Clostridium spp. (the cause of gangrene) are obligate anaerobes, they are capable of survival in deep tissue. The environment offered by decomposing tissue provides an ideal habitat for proliferation of these bacteria and release of toxins. Lyme disease is notably prevalent in Canada. It is most widely distributed in Atlantic Canada; however, the prairies have also reported wide distribution. As is the case in the United States, the major source of the infection is the presence of infected deer mice. It has been reported that individuals have been afflicted with Lyme disease after cleaning up the droppings of infected mice.
Why is urethritis, an infection of the urethra, frequently preliminary to further infections of the urinary tract?
Because it starts in the urethra and can travel up into the kidneys if left untreated.
What are the two most important body fluids involved in transmission of HIV?
Blood and Semen
Why does a chill indicate that a fever is about to occur?
Body increases rate of metabolism and shivering which raises temperature.
6) A child suffering from repeated bouts of a violent, high-pitched cough is brought to her physician's office. The physician is likely to diagnose infection by Streptococcus pneumoniae. Bordetella pertussis. Mycobacterium tuberculosis. Haemophilus influenzae.
Bordetella pertussis
It's time for: Name that Bacteria! A gram-negative coccobacillus.
Bordetella pertussis
What bacteria causes Pertussis?
Bordetella pertussis
Where does the Bordetella pertussis live in the body?
Bordetella pertussis adhere to and aggregate on the cilia of epithelial cells in the respiratory tract.
Describe Bordetella pertussis.
Bordetella pertussis is a gram-negative coccobacillus
How is pertussis spread?
Bordetella pertussis is spread by respiratory droplet
Hepatitis A
Causative Agent: -Hepatitis A virus -Picornaviridae Mode of Transmission: -Ingestion Site of Infection: Liver Symptoms: Anorexia, fever, joint pains, jaundice Prevention: Inactivated virus. Post exposure immune globuline
*What virus is the cause of Burkitt's lymphoma and infectiousmononucleosis? How are these diseases transmitted? How do the symptoms of these diseases differ?
Burkitt's Lymphoma-most common childhood cancer in Africa -caused by the Epstein-Barr virus (EB virus)-official nameis the human herpesvirus 4 -mosquito-borne malarial infections apparently foster the development of Burkitt's lymphoma by impairing the immune response to EB virus which is almost universally present in human adults worldwide. -the virus has become so adapted to humans that it is one of our most effective parasites -establishes lifelong infection in most ppl that is harmless and rarely causes disease -in areas w/o endemic malaria , such as the US- Burkitt's lymphoma is rare and usually abdominal -appearance of the lymphoma in AIDS patients is an indication of the importance of immune surveillance in preventing expression of the disease abdominal swelling. distortion of facial bones. night sweats. intestinal obstruction. an enlarged thyroid. enlarged tonsils. Infectious Mononucleosis (mono) -caused by EB virus --nearly 20% of adults in US carry EB viruses in oral secretions -childhood EB virus infections- usually asymptomatic -if infection is delayed until young adulthood, as is often the case in the US- the result is more symptomatic prob because of an intense immunological response -peak US incidence of the disease occurs at about age 15-25. -principal cause of the rare deaths is rupture of the enlarged spleen (common response to a systemic infection) during vigorous activity -recovery- usually completed in a few weeks and immunity is permanent. -usual route of infection: by transfer of saliva by kissing or by sharing drinking vessels -does not spread among casual hosthold contacts, so aerosol transmission is unlikely -EB virus- maintains a persistant infection in the mouth and throat which accounts for its presence in saliva -probably that resting memory B cells located in lymphoid tissue are the primary site of replication and persistence. -most symptoms are attributed to responses of T cells to the infection a fever. a sore throat. swollen lymph glands in the neck and armpits. a headache. fatigue. muscle weakness. swollen tonsils. night sweats.
What is a palisade layer?
C. diphtheriae bacilli remain in clumps after multiplying, forming a palisade layer.
C. diphtheriae produce an _____, encoded by a _______________ (lysogenized C. diphtheriae) that inhibits __________.
C. diphtheriae produce an exotoxin, encoded by a corynebacterium-containing prophage gene (lysogenized C. diphtheriae) that inhibits translation.
Describe the pathogenicity of Diptheria.
C. diphtheriae produce an exotoxin, encoded by a corynebacterium-containing prophage gene (lysogenized C. diphtheriae) that inhibits translation.
Survival with Aids Exposed, but not infected
CCR5 mutation, in the cd4 receptors. Effective CTLs
Define central nervous system and blood-brain barrier.
CNS- brain and spinal cord Blood-brain barrier- meninges that protect the brain and spinal cord
What is a common indication that someone has Stage 2 of HIV?
Candida albicans
Name two virulence factors of Bordetella pertussis.
Capsule and Pertussis toxin
Disease: Anthrax Causative Agent: Transmission: Reservoir:
Causative Agent: -Bacillus Anthracis Transmission: -Skin abrasions, inhalation, ingestion Reservoir: -soil, cattle
Disease: Lyme Disease Causative Agent: Transmission: Reservoir:
Causative Agent: -Borrelia burgdorferi Transmission: -Tick bites Reservoir: -Deer, mice
Disease: Brucellosis Causative Agent: Transmission: Reservoir:
Causative Agent: -Brucella spp. Transmission: -Ingestion of milk, direct contact Reservoir: -Cattle
Disease: Yellow fever Causative Agent: Vector: Treatment:
Causative Agent: -Flavivirus Vector: -Aedes aegypti Treatment: -None
Malaria
Causative Organism: Plasmodium parasite Transmission: by the Anopheles mosquito vector -disease of malaria and its symptoms- intimately related to its complex reproductive cycle -infection- initiated by bite of a mosquito- carries the sporozoite stage of the Plasmodium protozoan in its saliva -sporozoite enters bloodstream of bitten human -within 30 min- enters liver cells -sporozoites in liver cells undergo reproductive schizogony -results in release of about 30,000 merozoite forms into the bloodstream -merozoites- infect RBCs -within RBCs- they again undergo schizogony -after 48hrs- RBCs rupture and release about 20 new merozoites -many of released merozoites- infect other RBCs to renew the cycle in the bloodstream -some merozoites develop into male or female gametocytes -when these enter the digestive tract of a feeding mosquito- they pass through a sexual cycle that produces new infective sporozoites -Malaria - esp dangerous during pregnancy b/c adaptive immunity is suppressed. Reservoirs: Humans Symptoms: -chills and fever -vomiting -severe headaches -symptoms appear at intervals of 2-3 days alternating w/ asymptomatic periods Treatment: -2 considerations for antimalarial drugs: for prophylaxis (prevention) or for treatment Prophylaxis -when travelling to areas in which malaria is still sensitive to it- chloroquine is the drug of choice -in chloroquine-resistant areas- drug Malarone (combination of atovaquone and proguanil) is best tolerated -Travelers to malarial areas are often prescribed mefloquine (lariam) -WHO- recommends artemisinin combination therapies (ACT) for treatment of malaria worldwide -they are not used for prophylaxis -exmaples of artemisinin derivatives are artesunate and artemether -shortlived artemisinin component of ACT is intended to remove most of the parasties -partner drug, with an extended period of activity, is intended to eliminate the remainder -example of ACT is Coartem (artemether and lumefantrine)
Influenza
Causative agent: Clinical Manifestation: nausea and vomiting, but confusion and delirium may occur Treatment: bed rest, adequate fluid intake, and aspirin or Tylenol for fever and muscle pain Reservoir: humans, pigs, and birds. Source: trachea, bronchial tubes, and alveoli Transmission: transmitted through respiratory droplets, Prevention: good hygiene, vaccination
Campylobacter gastroenteritis
Causative agent: -Campylobacter jejuni Method of Transmission: -foodborne- undercooked meat and meat products -raw or contaminated milk -contaminated water or ice Symptoms: -Fever, abdominal pain, diarrhea Treatment: -None
Staphylococcal food poisoning
Causative agent: -S. aureus Method of Transmission: -ingesting foods contaminated w/ toxins Symptoms: -Nausea, vomiting, diarrhea Treatment: -None- oral rehydration therapy
Salmonellosis
Causative agent: -Salmonella enterica Method of Transmission: -person-to-person or -animal-to-person through fecal-oral route -ingestion of contaminated or improperly cooked foods Symptoms: -Nausea and diarrhea Treatment: Oral Rehydration
Shigellosis (bacillary dysentery)
Causative agent: -Shigella spp. Method of Transmission: -fecal, oral route -direct person-to-person contact -indirectly: contaminated food, water, fomites Symptoms: -Tissue damage and dysentery Treatment: -Quinolones
Cholera
Causative agent: -Vibrio cholerae O:1 and O:139 Method of Transmission: -fecal-oral route -ingesting contaminated food or water Symptoms: -Diarrhea with large water loss Treatment: -Rehydration; doxycycline
Travellers Diarrhea
Causative agent: -enterotoxigenic Escherichia coli Method of Transmission: -ingesting contaminated food/water Symptoms: -diarrhea, abdominal cramps Treatment: -Ciprofloxacin
Rabies
Causative agent: -ssRNA virus in the Rhabdoviridae family Clinical Manifestation:abnormal sensations such as tingling, burning, or coldness at the site of the bite. Fever, nausea, and vomiting also occur Treatment:postexposure immunizations, tetanus booster Transmission:enters the tissue and peripheral nervous system through a skin wound contaminated with the saliva of a rapid animal. Prevention:preventative immunization, avoiding rapid animals
Common Cold
Causative agent: 100 rhinovirus strains Clinical Manifestation: sneezing, sore throat, runny or stuffy nose, mild aches and pains, and mild-moderate hacking cough Treatment: Antihistamines can be used to treat the symptoms, but they do not shorten the length of the illness. Reservoir: lining of the nose, sinuses, throat, and upper airways Prevention: hand washing
Anthrax
Causative agent: Bacillus anthracis Clinical Manifestation: cold symptoms, sever breathing problems, shock, can be fatal,acute inflammation of the intestinal tract, which causes nausea, vomiting, and fever, abdominal pain, vomiting of blood, and severe diarrhea, red, bumpy, itchy skin Treatment: antibiotics, Reservoir: animals Source: soilborne endospores Transmission: inhalation of dust, consumption of undercooked meat, exposure of skin abrasions to spore-contaminated animal products Prevention: vaccinate animals
C. diff infection(Clostridium difficile infections)
Causative agent: C. diff Clinical Manifestation: diarrhea, severe inflammation of the colon can lead to a grossly dilated bowel Treatment:cessation of antibiotic therapy and fluid replacement. if severe, surgery for colon, anticlostridial antibiotics Reservoir:Feces Source:As a result of antibiotic therapy, intestinal microbiota is damaged, allowing resident or ingested C. diff to colonize regions of the GI tract. Transmission:In a healthcare setting, the endospores can be transferred to patient through healthcare workers who have touched the contaminated object through the fecal-oral Older adults and people under medical care who have been taking certain antibiotic for a prolonged period are most at risk.
Campylobacteriosis
Causative agent: Campylobacter jejuni Clinical Manifestation: mild diarrhea to bloody diarrhea and high fevers Treatment: rest, or if you want to speed up recovery antibiotics will work Reservoir: intestinal tract of warm blooded animals Source: contaminated food Transmission:fecal-oral route through contamination or exposure to contaminated food or water. Prevention: practicing good hygiene and proper food preparation
Candidiasis
Causative agent: Candida albicans Grows on mucosa of mouth, intestinal tract, and genitourinary tract NGU in males Vulvovaginal candidiasis, yeasty discharge pH: <4 Diagnosis: microscopic and culture Treatment: clotrimazole; fluconazole
List the causative agents, symptoms, methods of diagnosis, and treatments for lymphogranuloma venereum (LGV)
Causative agent: Chlamydia trachomatis Initial lesion on genitals heals Bacteria spread through lymph Symptoms: swelling in lymph nodes in groin Diagnosis: microscopic identification and culture Treatment: doxycycline
Impetigo
Causative agent: S. aureus Clinical Manifestation: blisters that ooze yellow fluid Treatment: topical or oral antibiotics, doctors may drain of clean area Reservoir: human Source: human Transmission: direct and indirect contact Prevention: good hygiene
Botulism
Causative agent: Clostridium botulinum Clinical Manifestation: blurred vision, slurred speech, difficulty swallowing and chewing, and labored breathing.Limbs lose their tone and become flabby, called flaccid paralysis. The toxin affects acetylcholine receptors, which leads to inhibition of muscle contraction. Treatment:It is treated with the use of an antitoxin, if caught early, which neutralize the unbound toxin. Life support may be used for those that have lost diaphragm function. Complete recovery can take up to a year. Reservoir:Endospores exist in the intestines of humans, fish, birds, and barnyard animals. They can reach the soil through manure, fertilizers, sewage. Source:When spores enter anaerobic environment of cans and jars, they germinate into vegetative bacilli and produce neurotoxin. Symptoms develop within 18 to 36 hours after Transmission:ingesting the toxin contaminated food Prevention: heating foods before eating them (destroys the toxin). Most outbreaks are associated with home-canning. Avoid bulging cans.
Gas gangrene
Causative agent: Clostridium perfringens Clinical Manifestation: massive tissue damage, body part becomes dry and shrunken, and the skin color changed to purplish or black. gas accumulates under skin, foul odor Treatment: removal of dead skin or amputate body part, oxygen chamber Reservoir: Animals Source: endospores in dirt Transmission: Gangrene develops when the blood flow ceases to part of the body, usually due to blockage by dead tissue. or contaminated dirt enters wound Prevention: hygiene
Tetanus
Causative agent: Clostridium tetani Clinical Manifestation: hyperactive muscle contraction, muscle spasms, stiffness, jaw will spasm, lockjaw, arching of back, decrease in ventilation Treatment: sedatives, muscle relaxers, quiet room, antibiotics, antitoxin Reservoir: animal manure Source: endospore Transmission:Spores enter the body through a deep puncture wound resulting from a fracture, gunshot, animal bite, or puncture by an object. Prevention: DTaP vaccine and Td vaccine
List the causative agents, symptoms, methods of diagnosis, and treatments for and bacterial vaginosis
Causative agent: Gardnerella vaginalis Symptoms: copious fishy, gray-white, thin, frothy discharge pH: >4.5 Diagnosis: clue cells Treatment: metronidazole
List the causative agents, symptoms, methods of diagnosis, and treatments for chancroid
Causative agent: Haemophilus ducreyi Symptoms: painful ulcers of genitals, swollen lymph nodes in groin Diagnosis: culture Treatment: erythromycin; ceftriaxone
Gastric Ulcer Disease
Causative agent: Helicobacter pylori Clinical Manifestation:nausea, vomiting, bloating, bloody vomit or stools, destruction of stomach lining Treatment:antibiotics such as amoxicillin, tetracycline, and clarithromycin. The acid reducer omeprazole is also prescribed Reservoir: human Source: human Transmission:mother-to-child, or contact with saliva Prevention: good hygiene It is still unknown how this organism causes cancer, but likely due to DNA damage in the stomach lining that is not repaired.
Leptospirosis
Causative agent: Leptospira interrogans Clinical Manifestation: muscle aches, eye inflammation, fever, chills, yellowing of skin and whites of eyes, inflammation of liver and lungs Treatment: antibiotics Reservoir: Animals Source: urine goes to soil or water Transmission: Human acquire it through direct contact with these animals or indirectly from soil, food, or water contaminated with urine from infected animals. Prevention:prophylactic antibiotic use for high risk individuals (farmers/vets/sewage workers). found in subtropical areas
Leptospirosis
Causative agent: Leptospira interrogans Reservoir: dogs and rats Transmission: skin/mucosal contact from urine-contaminated water Symptoms: headaches, muscular aches, fever; kidney failure a possible complication Diagnosis: serological test Treatment: doxycycline
Listeriosis
Causative agent: Listeria monocytogenes Clinical Manifestation: headache, fever, stiff neck Treatment: antibiotics Reservoir: animals, soil, and water Source: humans Transmission: consumption of contaminated food or water Prevention:washing of hands and materials used to prepare raw food, and thorough cooking of raw meats it can be affect pregnant women and the fetus
Hansens Disease (Leprocy)
Causative agent: Mycobacterium leprae Clinical Manifestation: symptoms occur in the skin and peripheral nervous system, such as the hands, feet, face, and earlobes, if severe there might be numb areas, skin and thickening of peripheral nerves and eventually maybe possible damage to the nerves Treatment: multidrug antibiotic therapy Reservoir: armadillos Transmission: contact with nasal secretions but it is hard to spread since most people are immune Prevention: avoiding contact where endemic
Neonatal Conjunctivitis
Causative agent: N. gonorrheae or C. trachomatis Clinical Manifestation:Symptoms include eye swelling and discharge. It can lead to permanent eye damage and even blindness. Treatment: antibiotic therapy Transmission: the inflammation of the conjunctiva of a newborn Prevention: the use of antibiotic eye drops places into the eyes of all newborns following delivery
Gonorrhea
Causative agent: Neisseria gonorrhoeae Clinical Manifestation: cervix may be reddened, discharge if there is pressure against pelvic, abdominal pain, a burning sensation while urinating, and normal menstruation cycle may be interrupted, spreading of fallopian tube males have less symptoms, mainly painful urination and eventually discharge, frequent urination Treatment: antibiotics Reservoir: humam Source: human Transmission: sexual transmission Prevention: std screening, practicing safe sex sensitive to dehydration so it does not survive long outside the body
Burn Infections
Causative agent: Pseudomonas aeruginosa Clinical Manifestation: can be difficult since signs and symptoms might be missing Treatment: antibiotics Prevention: rapid debridement and wound closure
Epidemic Typhus
Causative agent: Rickettsia prowazekii Clinical Manifestation: fever and rash, in severe cases there is permanent damage to blood vessels, heart, kidneys, and lungs Treatment: antibiotics Reservoir: humans Source: feces of lice Transmission: lice bite humans due to poor hygiene and scratching initiates it Prevention: practicing good hygiene
Rocky Mounted Spotted Fever
Causative agent: Rickettsia rickettii Clinical Manifestation: high fever, severe headache, skin rash reflecting damages to small vessels Treatment: antibiotics Reservoir: small mammals and humans Source: tick Transmission: tick bites Prevention: prompt tick removal
Staph Skin Infection(Boils)
Causative agent: Staphylococcus aureus Clinical Manifestation: causes Furuncles are warm, pain filled abscesses that develop in the region of a hair follicle while carbunclesare a group of connected, deeper abscesses. Treatment:A physician must open and drain the pus, and rinse with sterile saline water to remove any bacterial cells. The infection has potential to spread to the blood and be transported to other organs, such as the lungs, brain, heart, or kidneys. antibiotics Reservoir: human skin, mouth, nose, and throat Source: human Transmission: skin contact Prevention:good hygiene
Syphilis
Causative agent: Treponema pallidum Clinical Manifestation: painful purple lesion, if untreated flu like symptoms will occur and swollen lymph nodes and skin rah all over body, blood vessels weaken Treatment: antibiotics Reservoir:humans Source:humans Transmission: sexual intercourse Prevention: std screening, safe sex
Trichomoniasis
Causative agent: Trichomonas vaginalis Found in semen or urine of male carriers Vaginal infection causes irritation and profuse foul, greenish yellow frothy discharge pH: 5-8 Diagnosis: microscopic identification, DNA probe Treatment: metronidazole
Identify the causative agent, vector, symptoms, and treatment for African trypanosomiasis and amebic meningoencephalitis - What insect is the vector for African trypanosomiasis?
Causative agent: Trypanosoma brucei gambiense- chronic (2-4 years) or T. b. rhodesiense infection- acute (few months Vector: tsetse fly Symptoms: fever, headache, eventually coma and death Treatment: Eflornithine blocks an enzyme necessary for the parasite Tseste fly
Vibriosis
Causative agent: Vibrio parahaemolyticus Clinical Manifestation: acute abdominal pain, vomiting, watery diarrhea, and nausea, necrotic skin lesions Treatment:antibiotic therapy for prolonged illness Source: contaminated seafood Transmission: eating contaminated seafood Prevention:to properly cook seafood, especially oysters.
Plague
Causative agent: Yersinia pestis Clinical Manifestation: bubonic: swelling of nodes, dark purpilish splotches, low blood pressure septimic: high fever, diarrhea, and abdominal pain. pneumonic: headache, malaise, and coughing. water accumulation, cardiovascular collapse Treatment: antibiotics Reservoir: rats Source: fleas tat bit the rats Transmission: transmitted by fleas or contact with an infected animal (rat) and Pneumonic plague is usually transmitted from person to person through respiratory droplets Prevention: vaccine
Human Cytomegalovirus Disease
Causative agent: cytomegalovirus(CMV) is the largest member of Herpesviridiae Clinical Manifestation:mono like syndrome, including fever and malaise Treatment:Antivirals such as acyclovir Transmission: body fluid contact with an infected individual Prevention: no vaccine
Smallpox
Causative agent: ddDNA virus of the Poxviridae family called the variola virus Clinical Manifestation:high fever, headache, vomiting, and general body weakness, red-pink spots Treatment: vaccination Reservoir: humans Transmission: respiratory droplets or contact with the virus from skin lesions Prevention: vaccine no longer available
Cold Sores
Causative agent: herpes simplex virus Clinical Manifestation: tingling sensation and the presence of a small, hard spot on the lip, then red blisters, then it busts and a scab forms Treatment: antiviral drug acyclovir Transmission: most likely to occur from the time the blisters form until they have completely dried and crusted over Prevention: antiviral drug acyclovir
Genital Herpes
Causative agent: herpes simplex virus 2 Clinical Manifestation: itching or throbbing in the genital area, reddened and swelling Treatment: antiviral drugs, such as acyclovi Transmission: sexual contact Prevention:abstaining from sexual contact or liming sexual contact to one person that is infection-free. no cure for genital herpes
Warts(common/genital)
Causative agent: human papillomavirus (HPV)., 100 different types of icosahedral, naked, ddDNA virions from the Papovaviridae family Clinical Manifestation: warts on hands, fingers, and soles of feet, pink or white usually not painful Treatment: freezing or minor surgery Transmission: direct or indirect contact Prevention: remaining clean and not picking at the warts
Mumps
Causative agent: mumps virus, another member of the Paramyxoviridae family. Clinical Manifestation: enlarged jaw tissues arising from swollen salivary glands, especially the paratid glands Treatment: none Transmission: through respiratory droplets or contact with contaminated objects Prevention:MMR vaccine decreased sperm count
Polio
Causative agent: poliovirus of the Picornaviridae family. Clinical Manifestation:abortive poliomyelitis where the patient experiences fever, headache, sore throat, and nausea. Prevention: Both vaccines, the Salk and Sabin
Respiratory Syncytial Disease
Causative agent: respiratory syncytial virus Clinical Manifestation: flu-like Treatment:taking fever-reducing medications. Reservoir: bronchioles and air sacs of the lungs Transmission: transmitted through respiratory droplets or virus-contaminated hands. Prevention: good hygiene
Trachoma
Causative agent: serotypes A-C of Chlamydia trachomatis Clinical Manifestation: tiny, pale nodules that are rough in appearance Treatment: antibiotic therapy Transmission:contact with contaminated fingers, towels, and optical instruments. Face-to-face contact and flies are also modes of transmission. not transmitted through sexual contact
Varicella/Shingles
Causative agent: varicella-zoster virus (VZV) Clinical Manifestation: fever, headache, and malaise, red, itchy rash on the face, scalp, chest, and back, although it can spread across the entire body. Treatment: acyclovir, Zostavax Reservoir: respiratory tract and blood stream and then cutaneous tissue Source: human Transmission: respiratory droplets and skin contact Prevention: vaccine
Zika
Causative agent: zika virus (VIKV) Clinical Manifestation: rash, joint pain, and red eyes Treatment: supportive care Reservoir: infected humans and primates Transmission: mosquito bite, mother to fetus, sexual contact Prevention: no vaccine, insect repellant and appropriate clothing to avoid mosquito bites
A 20-year-old woman feels a stinging sensation when urinating and feels an urgent need to urinate, even if very little urine is excreted. Can you identify infections that could cause these symptoms?
Cystitis , Bladder infection
Discuss the epidemiology of anthrax. - How do animals such as cattle become victims of anthrax?
Caused by Bacillus anthracis Gram-positive, endospore-forming aerobic rod Found in soil Primarily affects grazing animals Spores introduced into the body are taken up by macrophages and germinate Bacteria enter the bloodstream and release toxins Treated with ciprofloxacin or doxycycline Vaccination of livestock Bacteria produces virulence factors Protective antigen: binds the toxins to target cells, permitting their entry Edema toxin: causes local swelling and interferes with phagocytosis Lethal toxin: targets and kills macrophages Amino acid capsule that avoids an immune response Cutaneous anthrax Endospores enter through a minor cut 20% mortality rate without treatment Gastrointestinal anthrax Ingestion of undercooked, contaminated food 50% mortality rate Inhalational (pulmonary) anthrax Inhalation of endospores Bacteria enter the bloodstream; progresses into septic shock Near 100% mortality rate
Lyme disease
Caused by Borrelia burgdorferi Most common tickborne disease in the United States Field mice are the most common reservoir Nymphal stage of the Ixodes tick feeds on mice and infects humans Ticks feed on deer, but are not infected Ticks must attach two to three days to transfer bacteria First phase Bull's-eye rash; flulike symptoms Second phase Irregular heartbeat; encephalitis; facial paralysis; memory loss Third phase Arthritis due to an immune response Diagnosis via ELISA, indirect fluorescent-antibody (FA) test, or Western blot Treated with antibiotics More difficult to treat in later stages
Discuss the epidemiology of tularemia. - What animals are the most common reservoir for tularemia?
Caused by Francisella tularensis Gram-negative rod Zoonotic disease Transmitted from rabbits, ticks, and insects by deer flies Creates an ulcer at the site of entry Bacteria reproduce in phagocytes Enlarges the regional lymph nodes Mortality usually <30%
Listeria monocytogenes
Caused by Listeria monocytogenes Gram-negative aerobic rod Usually foodborne; it can be transmitted to fetus reproduce in phagocytes
Neisseria menigitidis
Caused by N. meningitidis which is gram negative, aerobic cocci with a capsule 10% of people are healthhy nasopharyngeal carriers Begins as throat infection, rash Serotypes B,C, Y, W-135 in US Serotype B in Europe Serotype A in Africa, China, and Middle East Vaccination (B,C, Y, W-135 capsule) recommended for college students
Gonorrhea
Caused by Neisseria gonorrhoeae Attaches to oral or urogenital mucosa by fimbriae Opa proteins prevent proliferation of CD4+ T cells
List the causative agents, symptoms, methods of diagnosis, and treatments for gonorrhea,
Caused by Neisseria gonorrhoeae Symptoms Men: painful urination and discharge of pus Women: few symptoms but possible complications, such as PID Diagnosis: Gram stain, ELISA, PCR Treatment: cephalosporins
Rocky Mountain spotted fever
Caused by Rickettsia rickettsii Spread by wood ticks (Dermacentor andersoni) and dog ticks (Dermacentor variabilis) Measles-like rash, except that the rash also appears on the palms and soles Without early diagnosis, mortality rate is approximately 20% Treatment with tetracycline and chloramphenicol
Plague
Caused by Yersinia pestis Gram-negative rod Transmitted by the rat flea (Xenopsylla cheopis) Endemic to rats, ground squirrels, and prairie dogs Bacteria blocks the flea's digestive tract Flea bites the host and ingested blood is regurgitated into the host Bacteria enter the bloodstream and proliferate in the lymph tissue Cause intense swellings called buboes
Genital Herpes
Caused by herpes simplex virus 2 (human herpesvirus 2, or HSV-2) Painful vesicles on genitals Neonatal herpes transmitted to fetus or newborns Recurrences from viruses latent in nerves Suppression: acyclovir
CD4 Receptor
Cell the Virus binds too.
Dendritic cells considered primarily part of the humoral or the cellular immune system?
Cellular immune system
On what continent did the HIV-1 virus arise?
Central Africa
Clade C (half of all HIV infections)
Central Africa down to South Africa India and southeast Asia Parts of China
E coli is part of the normal microbiota of the intestines and can cause gastroenteritis. -Explain why this one bacterial species is both beneficial and harmful
Certain strains of E. coli may produce an enterotoxin or invade the epithelium of the large intestine.
Hemolytic uremic syndrome (HUS)
Damaged red blood cells clog the kidney glomerulus and can cause kidney damage
Describe the process of phagocytosis, and include the stages of adherence and ingestion.
Chemotaxis allows phagocytes to migrate to infection sites and destroy invading bacteria. Phagocytosis is the second line of defense. Phagocytes can also stimulate the T and B cells. Stages: 1) Chemotaxis and Adherence of the phagocyte to microbe. 2) Ingestion of microbe by phagocyte. 3) Formation of phagosome (phagocytic vesicle) 4) Fusion of phagosome with a lysosome to form a phagolysosome. 5) Digestion of ingested microbes by enzymes in the phagolysosome. 6) Formation of the residual body containing indigestible material. 7) Discharge of waste materials. (Figure 16.7, pg. 461)
One form of NGU is lymphogranuloma venereum caused by A) Leptospira interrogans. B) Chlamydia trachomatis. C) Neisseria gonorrhoeae. D) Treponema pallidum. E) Candida albicans.
Chlamydia trachomatis.
List the characteristics of diseases caused by prions - What are the recommendations for sterilizing reusable surgical instruments when prion contamination might be a factor?
Chronic and fatal, acquired by ingestion, inherited, or transplant, and they are very difficult to destroy Sterilization by NaOH and extended autoclaving at 134 C
15) Which of the following drugs is NOT used to treat infections caused by Mycobacterium tuberculosis? Ethambutol Isoniazid Rifampin Ciprofloxacin
Ciprofloxacin Ethambutol,Isoniazid, and Rifampin can be used to treat the infections caused by M. tuberculosis
How long does it take for clinical TB to develop?
Clinical TB develops within 3 months, and can be transmitted to others.
What is the function of cytokines?
Cytokines are a large group of proteins, peptides or glycoproteins that are secreted by specific cells of immune system. Cytokines are a category of signaling molecules that mediate and regulate immunity, inflammation and hematopoiesis.
Define Innate immunity.
Defenses against any pathogen, non specific.
Summarize the major outcomes of complement activation.
Complement proteins activate each other to destroy invading MO's. - Opsonization, or immune adherence: enhanced phagocytosis - Membrane attack complex: cytolysis - Attract phagocytes
Explain the basis for the complement-fixation test.
Complement-fixation reactions are serological tests based on the depletion of a fixed amount of complement in the presence of an antigen-antibody reaction.
Describe the modes of transmission for urinary and reproductive system infections.
Contaminated water, sexual intercourse, improper hygiene.
3) Methylene blue staining of metachromatic granules is diagnostic for Mycobacterium tuberculosis Corynebacterium diphtheriae Bordetella pertussis Streptococcus pyogenes None of the above is correct
Corynebacterium diphtheriae
It's time for: Name that Bacteria! Gram-positive rod with metachromic granules.
Corynebacterium diphtheriae
Describe Corynebacterium diphtheriae.
Corynebacterium diphtheriae is a Gram-positive rod.
What conditions are suitable for the spread of Mycobacterium tuberculosis?
Crowded conditions and poor ventilation contribute to disease spread of Mycobacterium tuberculosis. Malnutrition and poor quality of life also contribute to the establishment of the disease.
What type of diptheria infects the skin?
Cutaneous diphtheria. Infected skin wound leads to slow-healing ulcer.
*What are the causative agents of dental caries and periodontal disease?
Dental Caries: -Streptococcus mutans -gram-positive coccus -can metabolize a wide range of carbs, tolerates high level of acidity and synthesizes DEXTRAN- a gummy polysaccharide of glucose molecule which is an important factor in the formation of dental plaque Periodontal disease: -Porphyromonas- species found in these infections -damaging to tissue is done by an inflammatory response to the presence of these bacteria -streptococci, actinomycetes and anaerobic gram-negative bacteria predominate in gingivitis infections. -gingivitis can progress to chronic conditions like peridontitis -gums inflammed, blled -sometimes pus form in periodontal pockets -bone and tissue supporting teeth are destroyed- lossening and loss of teeth
What makes a natural killer cell, which is not immunologically specific, attack a particular target cell?
Destroy cells that don't express much MHC I. They don't require activation, kill virus-infected and tumor cells, which are often missing MHC antigens. Self vs. non-self discrimination: kills things that aren't self.
ELISA
Detects HIV antibodies
Western blotting
Detects HIV antigens
What is Diptheria?
Diptheria is a local infection of the throat caused by Corynebacterium diphtheriae. Diphtheria is acquired by respiratory droplet transmission
Explain how direct and indirect ELISA tests work.
Direct ELISA test - used to detect antigens against a specific antibody bound in a test well Indirect ELISA test - used to detect antibodies against an antigen bound in a test well
Certain diagnostic tests require red blood cells that clump visibly. What are these tests called?
Direct agglutination tests.
List the causative agents, symptoms, methods of diagnosis, and treatments for syphilis
Direct diagnosis Staining with fluorescent-labeled monoclonal antibodies Indirect, rapid screening VDRL, RPR, EIA
Which test is used to detect antibodies against a pathogen: the direct or the indirect fluorescent-antibody test?
Direct florescent-antibody test.
During the ___________ stage of pertussis, patients experience prolonged sieges of coughing, followed by an inhalation of breath that sounds like a "whoop"
During the "paroxysmal stage" patients experience prolonged sieges of coughing, followed by an inhalation of breath that sounds like a "whoop"
What are examples of non-microbial antigens?
Dust, dander, pollen, etc.
Explain how bacterial meningitis is diagnosed and treated.
Dx with spinal tap or lumbar puncture Tx antibiotics
How are antibodies detected in Western blotting?
Electrophoresis separates the protein mixture; it is transferred to a protein-binding sheet and flooded with an enzyme-linked antibody; the antigen is located with a color reacting label.
Gonorrhea If left untreated, may result in
Endocarditis( heart) Meningitis( brain) Arthritis( joints) Ophthalmia neonatorum (eyes)
What are two of the conditions that define the systemic inflammatory response syndrome of sepsis? - Are the endotoxins that cause sepsis from gram-positive or gram-negative bacteria?
Endotoxins & exotoxins Gram-negative
Enzyme immunoassay (EIA) test is used to diagnose _______________.
Enzyme immunoassay (EIA) test is used to diagnose Streptococcal Pharyngitis.
*List the vectors responsible for spreading typhus and describe the mode of action of this group of diseases
Epidemic Typhus (louseborne typhus) -carried by Rickettsia prowazekii -carried by human body louse (Pediculus humanus corporis) -pathogen grows in the GI tract of the louse and is excreted by it -transmitted when feces of louse are rubbed into the wound when the bitten host scratches the bite -disease flourishes in crowded and unsanitary surroundings, when lice can transfer readily from an infected host to a new host -produces a high and prolonged fever -- lasts at least 2 weeks -Stupor and a rash of small red spots- caused by subcutaneous hemorrhaging are characteristic, as the rickettsias invade blood vessel linings -Mortality rates are very high when disease is untreated -Endemic murine typhus- transmitted by the rat flee Xenophsylla cheopis -about 1 week after tick bites- macular rash develops that is sometimes mistaken for measles -it often appears on palms and soles though where viral rashes do not occur -rash accompanied by fever and headache
What toxin is produced by S. pyogenes?
Erythrogenic toxin is produced by lysogenized S. pyogenes
_____________ reduces the duration and severity of illness, but is not effective after onset of the ______________stage.
Erythromycin reduces the duration and severity of illness, but is not effective after onset of the paroxysmal stage.
How does Rickettsia avoid destruction by phagocytes?
Escape phagosome
Cystitis is most often caused by A) Escherichia coli. B) Leptospira interrogans. C) Candida albicans. D) Neisseria gonorrhoeae. E) Pseudomonas aeruginosa.
Escherichia coli.
Amoebic Dysentery (Amebiasis)
Etioloy: -Entamoeba histolytica Methods of Transmission: -food or water contamination by cysts of protozoan ameba Entamoeba histolytica Symptoms: -ameba lysis epithelial cells of the intestine, causes abscesses, significant mortality rate -severe dysentry- feces contain BLOOD and MUCUS -severe bacterial infections result if intestinal wall is perforated- abscesses can result Treatment: -Metronidazole plus iodoquinol
* List the etiology, methods of transmission, symptoms, and treatment of giardiasis, amoebic dysentery, and cryptosporidiosis. Giardiasis
Etioloy: -Giardia lamblia Methods of Transmission: -by drinking contaminated water supply Symptoms: -protozoan adheres to intestinal wall- may inhibit nutritional absorption -prolongued diarrhea, malaise, nausea, flatulence, weakness, weight loss, abdominal cramps -distinctive odor of hydrogen sulfide can be detected in breath or stools Treatment: metronidazole or quinacrine hydrochloride- effective within a week usually -new oral drug- nitazoxanide (both for cryptosporidiosis and giardiasis)
Cryptosporidiosis
Etioloy: -caused by protozoan Cryptosporidium usually C. parvum & C. hominis Methods of Transmission: -transmitted to humans largely through recreational and drinking water systems contaminated with oocysts of Cryptosporidium- mostly from animal waste -when humans ingest the cryptosporidian oocysts -oocysts- release sporozoites ino small intestine -motile sporozoites invade epithelial cells to intestine and undergo cycle that eventually releases oocysts to be excreted in feces Symptoms: -self-limiting diarrhea -fever, nausea, vomiting, lack of appetite, dehydration -may be life threatening in immunosuppressed patients Treatment: Nitazoxanide & Oral rehydration
Diferentiate among the following factors of bacterial intoxication and bacterial infection: -prerequisite conditions -causative agents -onset -duration symptoms -treatment Food Intoxication
Food Intoxication: -Microbes must be allowed to grow in food from the time of preparation to the time of ingestion. -usually occurs when foods are stored unrefrigerated or improperly canned -etiological agents: -Staphylococcus aureus or -Clostridium botulinum - the etiological agents must produce an exotoxin -Onset: 1-48 hrs -Duration: A few days -Treatment: Antimicrobial agents are ineffective. -patients symptoms may be treated
Disease: Subacute bacterial endocarditis Frequent Causative Agent: Predisposing Condition(s):
Frequent Causative Agent: -Alpha-hemolytic streptococcus Predisposing Condition(s): -Preexisting lesions
Disease: Acute bacterial endocarditis Frequent Causative Agent: Predisposing Condition(s):
Frequent Causative Agent: -Staphylococcus aureus Predisposing Condition(s): -Abnormal Heart Valves
Disease: Puerperal sepsis Frequent Causative Agent: Predisposing Condition(s):
Frequent Causative Agent: -Streptococcus pyogenes Predisposing Condition(s): -Abortion or Childbirth
Disease:Rheumatic fever Frequent Causative Agent: Predisposing Condition(s):
Frequent Causative Agent: Streptococcus pyogenes Predisposing Condition(s): Autoimmune
Are skin bacteria more likely to be gram+ or -?
G+
staphylococcal skin infections
G+ bacteria, form irregular clusters many produce coagulase *many produce coagulase (enzyme that clots fibrin in blood; used to identify types of staphylococci)
Streptococcal
G+ chains produce hemolysis that lyse RBC B-hemolytic streptococci often cause disease → Streptococci differentiated into groups A-T based on antigenic cell wall carbs
Why is Clostridium perfringens likely to grow in gangrenous wounds?
Gangrenous tissue is anaerobic and has suitable nutrients for C. perfringens
What are the signs of pertussis?
General malaise, low-grade fever and increasingly severe cough.
A pelvic examination of a 23-year-old woman showed vesicles and ulcerated lesions on her labia. Cultures were negative for Neisseria and Chlamydia; the VDRL test was negative. Which of the following is probable? A) Candidiasis B) Genital herpes C) Gonorrhea D) NGU E) Syphilis
Genital herpes
Describe the role of normal microbiota in innate immunity.
Good flora competes with potential pathogens. They consume nutrients, create an unfavorable environment for pathogens, help stimulate WBC's, provide vitamins (K and B's).
What is the most common mode, worldwide, by which HIV is transmitted?
Heterosexual intercourse.
The current treatment that is used for AIDS is
Highly Active Antiretroviral Therapy (HAART).
HAART
Highly active antiretroviral therapy Combinations of nucleoside reverse transcriptase inhibitors plus Non-nucleoside reverse transcriptase inhibitor or Protease inhibitor
Defense of the genital and urinary tract
In males, only the urethra is colonized with microbiota. The prostate produces a slightly milky fluid that contains an antibacterial compound to combat UTIs. Local immune responses provide antibodies along the entire length of the urethra and in seminal fluid.In females, the vagina, vulva, and cervix are colonized with microbiota. The vagina has an acidic pH in which Lactobacillus species thrive. This acidic environment discourages the growth of potential pathogens.Dysbiosis in vaginal microbiota is common for up to one year following childbirth.The cervix contains several antimicrobial defense mechanisms, including mucus and antibody production.
What is a Lancefield group?
In streptococci, groups A and B (Lancefield groups) are the most important to human disease.
Which test is used to detect antibodies against a pathogen, direct or the indirect ELISA test?
Indirect florescent-antibody test.
Is a tuberculosis infection always obvious?
Individuals may never even know they are infected with tuberculosis though they have a positive tuberculin test.
Define conjunctivitis.
Inflammation of the conjunctiva - AKA as pink eye or red eye
Describe the epidemiologies of endocarditis - What medical procedures are usually the cause of endocarditis?
Inflammation of the endocardium Subacute bacterial endocarditis Impairs the function of the heart valves Alpha-hemolytic streptococci from an oral or tonsil infection Acute bacterial endocarditis Caused by Staphylococcus aureus Pericarditis Inflammation of the sac around the heart Streptococci
24: Inflammatory and invasive gastroenterics
Inflammatory gastroenteritis is characterized by watery diarrhea and/or vomiting, usually cause a fever, but there is no blood in stool. Symptoms are of short duration (1 to 3 days) and noninvasive. Inflammatory:CholeraETECC. diff infectionsVibriosis Invasive gastroenteritis involves damage to intestinal mucosa caused by invasion of pathogens or toxins. Signs and symptoms include diarrheabut very little vomiting. Invasive:Typhoid feverSalmonellosisShigellosisHemorrhagic ColitisCampylobacteriosisListeriosis Gastric Ulcer Disease
Clade B
North and South America and Europe
What is margination?
Is the process in which free-flowing leukocytes exit the central blood stream, and initiate leukocyte and endothelial cell interactions by close mechanical contact.
Discuss the epidemiology of gas gangrene. - Why are hyperbaric chambers effective in treating gas gangrene?
Ischemia: loss of blood supply to tissue Necrosis: death of tissue Gangrene: death of soft tissue Gas gangrene Caused by Clostridium perfringens, a gram-positive, endospore-forming anaerobic rod Grows in necrotic tissue Produces toxins that move along muscle bundles Treatment includes the surgical removal of necrotic tissue and/or use of a hyperbaric chamber
What happens to the DNA that is made from the reverse transcriptase?
It becomes apart of the chromosomal DNA of the host cell
Why can the antibiotic chloramphenicol readily cross the blood-brain barrier, whereas most other antibiotics cannot?
It can cross because its a lipid soluble
Why is the plague-infected flea so eager to feed on a mammal?
It feeds of blood in order to survive. It's digestive tract needs more blood.
What is meant by GAS?
Physicians refer to as GAS (group A streptococci)
21-11 List the causative agent, mode of transmission, and clinical symptoms of these infections: herpetic keratitis, Acanthamoeba keratitis.
Keratitis -inflammation of the cornea -bacterial (US) -Fusarium and Asperigillus (Africa and Asia) Herpetic keratitis -caused by herpes simplex virus 1 (HSV-1) -infects cornea and may cause blindness -treated with trifluridine Acanthamoeba keratitis -Amoeba transmitted via water and soil -Associated with unsanitary contact lenses -mild inflammation followed by severe pain -treatment with propamidine isethionate and neomycin -may require a corneal transplant
How does Staphylococcus aureus avoid destruction by phagocytes?
Kill phagocytes: Leukocidins
Explain the importance of monoclonal antibodies.
Laboratory produced molecules that are set to mimic antibodies in your body by attaching to defects in cancer cells. The monoclonal antibodies make it easier for the immune system to recognize cancerous cells as dangerous. They are uniform, highly specific, and can be produced in large quantities. (used for cancer, crohns disease, asthama, and multiple sclerosis)
Define monoclonal antibodies, and identify their advantage over conventional antibody production.
Laboratory produced molecules that are set to mimic antibodies in your body by attaching to defects in cancer cells. The monoclonal antibodies make it easier for the immune system to recognize cancerous cells as dangerous. They are uniform, highly specific, and can be produced in large quantities. (used for cancer, crohns disease, asthama, and multiple sclerosis).
Normal microbiota of the adult vagina consist primarily of
Lactobacillus.
The Lower Respiratory Tract includes...
Larynx Trachea Bronchial tubes Alveoli Pleura
Which disease does Ebola hemorrhagic fever more closely resemble, Lassa fever or Hantavirus pulmonary syndrome?
Lassa fever
Does circumcision make a man more or less likely to acquire HIV infection?
Less: because of hygiene issues with an uncircumcised penis.
Name one common disease that may be associated with chronic fatigue syndrome
Lyme disease
Identify the vector, etiology, and symptoms of five diseases transmitted by ticks.
Lyme disease Rocky Mountain spotted fever Tularemia
Which of the following is caused by Chlamydia? A) Gardnerella vaginosis B) Genital herpes C) Candidiasis D) Trichomoniasis E) Lymphogranuloma venereum
Lymphogranuloma venereum
How does Listeria monocytogenes avoid destruction by phagocytes?
Lyse phagocytes: Membrane attack complex
9) Streptococcus pyogenes produces a protein that, anchored in the cell wall and cell membrane, allows the bacterial cells to adhere firmly to the pharyngeal tissue. This protein is called M protein X factor Y factor S protein
M protein
M. avium-intracellulare complex infects people with late-stage _____ infection.
M. avium-intracellulare complex infects people with late-stage HIV infection.
_____________complex infects people with late-stage __________ infection
M. avium-intracellulare complex infects people with late-stage HIV infection.
How many Mycobacterium tuberculosis cases are in the USA?
M. bovis: <1% U.S. cases; not transmitted from human to human
The blood of an infected cow would have a considerable amount of antibodies against the infectious pathogen in its blood. How would an equivalent amount of monoclonal antibodies be more useful?
Mabs: specific antibodies produced in vitro by a clone of B cells hybridized with cancerous cells. -they are uniform -they are highly specific
How has the development of monoclonal antibodies revolutionized diagnostic immunology?
Makes available large, economical amounts of specific antibodies, allowing for many newer diagnostic tests that are more sensitive, specific, rapid, and simpler.
Discuss the worldwide effects of these diseases on human health. - Eliminating which of these diseases, malaria or Chagas' disease, would have the greater effect on the well-being of the population of Africa?
Malaria
What is the Tuberculin skin test called?
Mantoux test
postpolio syndrome
Many people who had polio decades ago are now experiencing muscle weakness and atrophy, general fatigue and exhaustion, and breathing and swallowing problems
Ebola hemorrhagic fever
Marburg virus, Lassa fever, and Ebola virus PATHOGEN: Filovirus, arenavirus Portal of Entry: Mucous membranes SYMPTOMS: initial symptoms are headache and muscle pain; a few days later, victim begins to vomit blood and bleed profusely RESERVOIR: Possibly fruit bats and other small mammals MOT: Contract with blood TREATMENT: none
What does the ciliary escalator movement do?
Picks up MO from the lower respiratory to move up through the respiratory system to be excreted by coughing or sneezing.
Differentiate meningitis from encephalitis.
Meningitis- inflammation of the meninges Encephalitis- inflammation of the brain
What are metachromic granules?
Metachromic granules can be seen in C. diphtheriae and are seen in the club-shaped bacterium when stained with methylene blue.
____________ is the development of active tubercles throughout the body. What happens during this kind of infection?
Miliary tuberculosis is the development of active tubercles throughout the body. The body's remaining defenses are overwhelmed, and the patient suffers weight loss, coughing (often bringing up blood), and great loss of vigor.
Miliary tuberculosis is the development of _______________ throughout the body. What is another name for this infection?
Miliary tuberculosis is the development of active tubercles throughout the body. Also known as "consumption".
Moons Molar
Misshapen tooth caused by syphilis that misshapes the tooth.
Syphilis skin rash
Moth macular and papular, as well as invasive.
What is Multidrug-resistance Mycobacterium tuberculosis? How is it treated?
Multidrug-resistance Mycobacterium tuberculosis is affecting which antibiotics are used to treat TB (ethambutol and streptomycin). Rifapentine is taken once a week.
A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. The etiology could be any of the following EXCEPT A) Borrelia. B) Mumps virus. C) Rickettsia. D) Streptococcus. E) Treponema.
Mumps virus.
Aids Vaccine Difficulties
Mutations Clades Antibody-binding sites "hidden" Infected cells not susceptible to CTLs Proviruses Latent viruses
14) This microorganism was long thought to be a harmless occasional member of the respiratory microbiota. However, the advent of the AIDS epidemic has unmasked it as an important opportunistic pathogen-and the cause of the most common mycobacterial infection among AIDS patients in the United States Mycobacterium bovis Mycobacterium tuberculosis Mycobacterium avium Mycobacterium leprae
Mycobacterium avium
10) BCG vaccine protects against which of the following? Bordetella pertussis Corynebacterium diphtheriae Neisseria meningitidis Mycobacterium tuberculosis
Mycobacterium tuberculosis
It's time for: Name that Bacteria! An acid-fast rod transmitted from human to human
Mycobacterium tuberculosis
Mycobacterium tuberculosis Facts: Because of the ____________, TB bacteria can survive for months in dry sputum only about ______ cells are required for infection the disease may be arrested if the early tubercles become ____________ extremely dangerous multiple drug-resistant strains have emerged
Mycobacterium tuberculosis Facts: because of the waxy cell walls, TB bacteria can survive for months in dry sputum only about 3-10 cells are required for infection the disease may be arrested if the early tubercles become calcified extremely dangerous multiple drug-resistant strains have emerged
How does Mycobacterium tuberculosis enter the body?
Mycobacterium tuberculosis enters the respiratory tract in small aerosolized droplets.
Describe Mycobacterium tuberculosis. How is it transmitted?
Mycobacterium tuberculosis is an acid-fast rod transmitted from human to human
21-6 Differentiate cutaneous from subcutaneous mycoses and provide an example of each
Mycosis: fungal infection of the body Cutaneous mycoses -colonize the hair, nails and outer epidermis -metabolize keratin -dermatomycoses -informally known as tineas or ringworm -tinea capitis: scalp ringworm -tinea cruris: jock itch -tinea pedis: athletes foot -tinea unguium: ringworm of nails Cutaneous mycoses )cont'd) -Genera of fungi involved -Trichophyton -Microsporum -Epidermophyton -Treatment is usually topical drugs (miconaozole and clotrimazole) Subcutaneous Mucoses -more severe than cutaneous mycoses -penetrate the stratum corneum; cutaneous fungi cannot do this -usually caused by fungi that inhabit the soil; penetrate through wounds -Sporotrichosis -caused by Sprorthrix schenkii dormophic fungus -enters a wound; forms a small ulcer -treated with potassium iodide
What are the cells that work together to kill cancer cells and infected cells by using perforins and granzymes?
NK cells and CTL
What are the first phagocyte to come to the site of infection?
Neutrophils
Can a mosquito bite, hugging, or kissing cause a transfer of HIV?
No
Does HIV infection=AIDS?
No AIDS is the final stage of HIV which is a much larger portion than just that one stage
Explain the value of vaccines, and discuss acceptable risks for vaccines.
No vaccine will ever be perfectly safe or perfectly effective (or any antibiotic or drug for that matter). Vaccines are still the safest, most effective means of preventing infectious disease in children.
A 26-year-old woman has abdominal pain, painful urination, and a fever. Cultures grown in a high-CO2 environment reveal gram-negative diplococci. Can you identify infections that could cause these symptoms?
Nongonococcal Urethritis
The upper respiratory tract includes....
Nose Pharynx (throat) Middle ear Eustachian tubes
Chemotherapy
Nucleoside reverse transcriptase inhibitors Non-nucleoside reverse transcriptase inhibitors Protease inhibitors Fusion inhibitors
Discuss the epidemiology of meningitis caused by Haemophilus influenzae
Occurs mostly in children (6 months - 4 years) Gram negative aerobic bacteria, normal throat microbiota Capsule antigen type b Prevented by Hib vaccine
21-10 List the causative agent, mode of transmission, and clinical symptoms of these eye infections: ophthalmia neonatorum, inclusion conjunctivitis, trachoma.
Ophthalmia neonatorum - caused by Neisseria gonorrhoeae, transmitted through birth into eyes, large amount of pus forms, ulceration of comeas results and untreated cases may lead to blindness Inclusion conjunctivitis - caused by Chlamydia trachomatis, transmitted through birth canal, spread though swimming pool water - bacteria that grows as a obligate intracellular parasite trachoma - Caused by serotypes of Chlamydia trachomatis,
What comes under the second line of defense?
Opsonization, Phagocytosis, inflammation, fever, Complement (Interferon).
21-10 List the causative agent, mode of transmission, and clinical symptoms of these eye infections: ophthalmia neonatorum, inclusion conjunctivitis, trachoma.
Opthalmia -caused by Neisseria gonorrhoeae -Large amount of pus forms; ulceration of corneas results; untreated cases may lead to blindness -Transmitted to a newborn's eyes during passage through the birth canal -Prevented by treated a newborn's eyes with antibiotics Inclusion Conjunctivitis -caused by Chlamydia trachomatis ; bacterium that grows as a obligate intracellular parasite -Transmitted to a newborn's eyes during passage through the birth canal -Spread through swimming pool water; swimming pool conjunctivitis -Treated with tetracycline Trachoma -caused by some serotypes of Chlamydia trachomatis -leading cause of blindness worldwide -transmitted via hand contact or flies -infection causes permanent scarring; scars abrade the cornea, leading to blindness; secondary infections can also be a factor -oral azithromycin are used in treatment
Thrush
Oral Candidiasis
What is the name of a currently used oral vaccine that occasionally causes the disease it is intended to prevent?
Oral polio
pharyngeal gonorrhea
Oraly transmitted,Present in the mouth
21-7 List the causative agent and predisposing factors for candidiasis
Overgrowth of Candida albicans (yeast) -Forms psudohyphae, making it resistant to phagocytosis Occurs in the skin and mucous membranes of the genitourinary tract and mouth -Trush: C. albicans infection of the oral cavity Results when antibiotics suppress competing bacteria or a change occurs in the mucosal pH Fulminating (sudden and severe) disease in the immunosuppressed
Babesiosis
PATHOGEN: Babesia microti SYMPTOMS: fever and chills at intervals RESERVOIR: Rodents MOT: Ixodes ticks TREATMENT: Atovaquone and azithromycin
Hantavirus pulmonary syndrome.
PATHOGEN: Bunyavirus Portal of Entry: Respiratory tract SYMPTOMS: Pneumonia RESERVOIR: Field mice MOT: Inhalation (of viruses in dried urine and feces from infected small rodents) TREATMENT: none
Chikungunya fever
PATHOGEN: Chikungunya virus SYMPTOMS: Fever; joint pain (esp. in the wrists, fingers, and ankles), often a rash appears and sometimes massive blisters RESERVOIR: Humans MOT: Aedes mosquito TREATMENT: Supportive The Aedes mosquito spreads the disease primarily in Asia and Africa.
CMV inclusion disease
PATHOGEN: Cytomegalovirus SYMPTOMS: mostly asymptomatic; initial infection acquired during pregnancy can be damaging to fetus RESERVOIR: Humans MOT: Body fluids TREATMENT: Ganciclovir, fomivirsen
Infectious mononucleosis
PATHOGEN: EB virus SYMPTOMS: Fever, general weakness RESERVOIR: Humans MOT: Saliva TREATMENT: none
Burkitt's lymphoma - Although not a disease with an insect vector, why is Burkitt's lymphoma most commonly a disease found in malarial areas?
PATHOGEN: Epstein-Barr virus (EB virus) SYMPTOMS: Tumor RESERVOIR: UNKNOWN MOT: also UNKNOWN TREATMENT: Surgery
Dengue
PATHOGEN: Flavivirus (dengue fever virus) Portal of Entry: Skin SYMPTOMS: Fever, severe muscle and joint pain, rash RESERVOIR: Humans MOT: Aedes aegypti mosquito; Aedes albopictus mosquito TREATMENT: no specifc treatment
Yellow fever - Why is the mosquito Aedes albopictus a special concern to the populations of temperate climates?
PATHOGEN: Flavivirus (yellow fever virus) Portal of Entry: Skin SYMPTOMS: Fever, chills, headache; jaundice RESERVOIR: Monkeys MOT: Aedes aegypti mosquito TREATMENT: no specific treatment DIAGNOSIS: usu. by clinical signs and can be confirmed by a rise in antibody titer or isolation of the virus from the blood. Vaccine available.
Leishmaniasis
PATHOGEN: Leishmania spp. SYMPTOMS: L. donovani: systemic disease. L. tropica: skin sores. L. braziliensis: disfiguring damage to mucous membranes. RESERVOIR: Small mammals MOT: Sandfly TREATMENT: Antimony compounds
Malaria
PATHOGEN: Plasmodium spp. MORPHOLOGY: protozoan parasite SYMPTOMS: chills, fever; vomiting and sever headache RESERVOIR: Humans MOT: Anopheles mosquito TREATMENT: Chloroquine
Epidemic typhus - Which disease is tickborne: epidemic typhus, endemic murine typhus, or Rocky Mountain spotted fever?
PATHOGEN: Rickettsia prowazekii MORPHOLOGY: aerobic, Gram-negative, obligately intracellular parasite SYMPTOMS: High fever, stupor, rash of small red spots RESERVOIR: Squirrels MOT: Pediculus humanus corporis louse TREATMENT: Tetracycline; chloramphenicol The disease can flourish only in crowded unsanitary surroundings, when lice can transfer readily from an infected host to a new host *Rocky Mountain spotted fever
Endemic murine typhus
PATHOGEN: Rickettsia typhi SYMPTOMS: Fever; rash RESERVOIR: Rodents MOT: Xenopsylla cheopsis flea TREATMENT: Tetracycline; chloramphenicol Murine is latin for mouse. Rat control is the best preventive measure.
Diagram the life cycle of Schistosoma, and show where the cycle can be interrupted to prevent human disease. - What freshwater creature is essential to the life cycle of the pathogen causing schistosomiasis?
PATHOGEN: Schistosoma spp. MORPHOLOGY: small fluke (HELMINTH) SYMPTOMS: Inflammation and tissue damage at site of granulomas RESERVOIR: definitive host; humans MOT: Cercariae penetrate skin TREATMENT: Proziquantel; oxamniquine Aquatic snails are an intermediate host.
Toxoplasmosis
PATHOGEN: Toxoplasma gondii MORPHOLOGY: spore-forming protozoan SYMPTOMS: Mild disease; initial infection acquired during pregnancy can be damaging to fetus; serious illness in AIDS patients RESERVOIR: Domestic cats MOT: Ingestion TREATMENT: Pyrimethamine, sulfadiazine, and folinic acid It is an intracellular parasite usually acquired by ingesting undercooked meats containing tachyzoites or tissue cysts; can also be contracted by direct contact with cat feces.
Chagas' disease
PATHOGEN: Trypanosoma cruzi MORPHOLOGY: flagellated protozoan SYMPTOMS: damage to heart muscle or peristaltic movement of gastrointestinal tract RESERVOIR: Rodents, opossums MOT: Reduviid bug ("kissing bug") TREATMENT: Nifurtimox DIAGNOSIS: usu. based on symptoms Disease primarily occurs in Central America and parts of South America.
Types of leprocy
Paucibacillary (tuberculoid) leprosy is a more limited disease with few bacterial in the skin and nerves. Multibacillary (lepromatous) leprosy is more a widespread, contagious disease involving larger numbers of infecting bacilli producing skin lesions.
Penicillin and clarithromycin can be used to treat ___________________.
Penicillin and clarithromycin can be used to treat Strep throat and scarlet fever.
Name a few diseased of the lower respiratory tract.
Pertussis Tuberculosis Pneumococcal pneumonia Primary typical pneumonia Legionaires' disease
What type of disease is Scarlett Fever?
Pharyngitis
Name a few diseases of the upper respiratory tract.
Pharyngitis Laryngitis Tonsillitis Sinusitis Epiglottitis: H. influenzae type b Strep throat Scarlet fever Diphteria
The Stages of HIV Infection
Phase 1: Asymptomatic or chronic lymphadenopathy Phase 2: Symptomatic; early indications of immune failure Phase 3: AIDS indicator conditions
21-4 List the causative agent, mode of transmission, and clinical symptoms of Pseudomonas dermatatis, otitis externa, and acne
Pseudomonas aeruginosa -gram negative, aerobic rod; soil and water; grows on unusual organic matter -Pyocyanin produces a blue green pus -Produces exo- and endotoxins; grows in biofilms; health care associated infections Pseudomonas dermatitis -Self limiting rash acquired in swimming pools Otitis externa -"Swimmer's ear" -Opportunistic in burn patients and cystic fibrosis patients (biofilm) -Resistant to many antibiotics Acne -Skin cells shed in high amounts in the hair follicles and combine with sebum; causes blockage; whitehead forms as sebum accumulates; blackhead forms in protrudes through the skin and lipid oxidation occurs -Sebum formation is affected by hormones, not diet -Comedonal (mild) acne ; easily treated with topical formations -Inflammatory (moderate) acne; caused by Proionbacterium acnes; anaerobe found on the skin; metabolizes sebum; fatty acids produce an inflammatory response; treated with antibiotics and benzoyl peroxide -Nodular cystic (severe) acne; inflammed lesions with pus deep in skin; leaves scars
A positive LE text and 10,000 CFU/ml in urine indicates
Pyelonephritis.
Pneumocystis
Really virulent form of pneumonia found in many aids patients in 1981.
What relationship do Toll-like receptors have to pathogen-associated molecular patterns?
Recognize and detect presence, recognition factor.
Which type of vaccine did Louis Pasteur develop, whole-agent, recombinant, or DNA?
Recombinant
V. cholerae
Suspect Foods: -Water Treatment: -rehydration -doxycycline Prevention: -drinking safe water
21-8 List the causative agent, mode of transmission, clinical symptoms and treatment of scabies and pediculosis
Scabies -caused by Sarcoptes scabiei mites; burrow in the skin to lay eggs -Causes inflammatory skin lesions -transmitted via inmate contact -500,000 cases in the US each year -Treatment with permethrin Pediculosis (Lice) -Pediculus humanus capitis (head louse) -P.h. corporis (body louse); only the body louse spread diseases such as typhus -Feed on blood from the host -Lay eggs (nits) on the hair and attach to the shafts -treatment with topical insecticides (permethrin or pyrethrin) ; Malathion, lindane, or ivermectin are used in cases of resistance; fined tooth combs; professional removal services in some cities
A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. Diagnosis was based on serological testing. The patient then reported that he had an ulcer on his penis 2 months earlier. What stage of disease is the patient in? A) NGU B) Primary C) Secondary D) Tertiary
Secondary
Diagnostic Methods
Seroconversion ELISA Plasma viral load (PVL) Western blotting
A 25-year-old man presented with fever, malaise, and a rash on his chest, arms, and feet. Which of the following will be most useful for a rapid diagnosis? A) Bacterial culture B) Microscopic examination of blood C) Serological test for antibodies D) Serological test for antigen E) Viral culture
Serological test for antibodies
Define interferons.
Small proteins released from virally infected cells that bind to near-by non-infected cells. - Interferons are species and tissue specific in the host but not virus specific. - Three types: alpha (α) and beta (β) from WBC's and gamma (γ) from activated T-cells.
Cryptococcosis - What is the most common source of airborne cryptococcal infections?
Soil fungus associated with pigeon and chicken droppings transmitted by the respiratory route; spreads through blood to the CNS Mortality up to 30% Treatment: Amphotericin B and flucytosine Pigeon/chicken droppings
21-3 Differentiate staphylococci from streptococci, and name several skin infections caused by each
Staphylococci -Spherical gram positive bacteria; form irregular clusters -Many produce coagulase; Enzyme that clots fibrin in the blood; used to identify types of staphylococci -Scalded skin syndrome; bollous impetigo liquid filled vesicles; Toxin B causes the exfoliation -Toxic Shock Syndrome (TSS) Fever vomiting shock and organ failure caused by toxic shock syndrome toxin 1 (TSST-1) in the bloodstream Potentially life threatening Streptococci -Gram postive cocci in chains, -Produce hemolysin that lyse red blood cells, -Beta hemolytic streptococci often case disease -Streptococci are differentiated into groups A through T based on antigenic cell wall carbohydrates -Group A streptococci (GAS), also known as Streptococcus pyogenes; 80 immunological types; produce virulence factors -Steptolysins: lyse RBCs -M proteins: external to the cell wall; allow adherence and immune system avoidance -Hyaluronidase: dissolve connective tissue -Steptokinases: dissolve blood clots Erysipelas -S. pyogenes infects the dermal layer of the skin it starts as a rash; causes local tissue destruction and sepsis, it appears first on the face and is often preceded by streptococcal soar throat and it is still sensitive to antibiotics -Necrotizing fasciitis has 15,000 cases in the US each year with mortality rates of 40%, "flesh eating" disease, exotoxin A produced by S. pyogenes acts as a super antigen causing the immune system to contribute to the damage, associated with streptococcal toxic shock syndrome; similar to staphylococcal TSS; higher mortality rate
How might one treat strep throat and scarlet fever?
Strep throat and scarlet fever can be treated by the antibiotics penicillin and clarithromycin
How severe are Streptococcal Diseases?
Streptococcal Diseases can be mild to severe.
What is the medical term for strep throat?
Streptococcal Pharyngitis
How is Streptococcal Pharyngitis diagnosed?
Streptococcal Pharyngitis is diagnosed by enzyme immunoassay (EIA) tests.
Besides the grouping based on red blood cell lysis, how else can streptococci be classified? What kind of classification is this?
Streptococci can also be classified according to variants of a carbohydrate in the cell wall. This is serological classification.(serotypes)
Streptococci can also be classified according to variants of a __________________________. This is _______________________.
Streptococci can also be classified according to variants of a carbohydrate in the cell wall. This is serological classification.(serotypes)
Give an example of a Streptococcus Lancfield group B. Provide two examples of infection.
Streptococcus agalactiae is a member of the group B. Streptococcus agalactiae causes major sepsis in newborns and post-partum infections in women.
What bacteria causes Scarlett Fever?
Streptococcus pyogenes
What causes Streptococcal Pharyngitis?
Streptococcus pyogenes
How does Streptococcus pyogenes cause Streptococcal Pharyngitis?
Streptococcus pyogenes enters the upper respiratory tract through respiratory droplets. Secreted toxins damage the surrounding human cells and lead to inflammation of the oropharynx and tonsils.
____________________ enters the upper respiratory tract through respiratory droplets. Secreted _______ damage the surrounding human cells and lead to inflammation of the ____________ and ___________.
Streptococcus pyogenes enters the upper respiratory tract through respiratory droplets. Secreted toxins damage the surrounding human cells and lead to inflammation of the oropharynx and tonsils.
Give an example of a Streptococcus Lancfield group A.
Streptococcus pyogenes is the most common species of the group A.
Streptokinases lyse _____ Streptolysins are __________
Streptokinases lyse clots Streptolysins are cytotoxic
What is the difference between Streptokinases and Streptolysins?
Streptokinases lyse clots Streptolysins are cytotoxic
Which is more likely to be useful in preventing a disease caused by an encapsulated bacterium such as the pneumococcus: a subunit vaccine or a nucleic acid vaccine?
Subunit: contains antigenic fragments (nucleic- vaccine made up of DNA in the form of plasmid)
How does Coxiella burnettii avoid destruction by phagocytes?
Survive in phagolysosome
Campylobacter jejuni
Suspect Foods: -Chicken Treatment: -None Prevention: Cooking
Staphylococcus aureus
Suspect Foods: -Creamy, salty Treatment: None Prevention: Refrigerating food
Clostridium perfringens
Suspect Foods: -Meat Treatment: -Oral rehydration Prevention: -Refrigeration after cooking
Vibrio parahaemolyticus
Suspect Foods: -Oysters, shrimp Treatment: -rehydration, antibiotics Prevention: Cooking
Bacillus cereus
Suspect Foods: -Rice dishes Treatment: -None Prevention: -Refrigeration after cooking
What is Phase 2 in HIV?
Symptomatic
HIV Phase 2
Symptomatic; early indications of immune failure. You catch diseases you already had. Known as Positive
Gummas
Syphilis in the body causing lesions internaly on organs seen in the tertiary stage
(T/F) Lower respiratory system is sterile.
T
Which T cell type is generally involved when a B cell reacts with an antigen and produces antibodies against the antigen?
T helper cells
Differentiate T helper, T cytotoxic, and T regulatory cells.
T helper: produces cytokines T cytotoxic: Type of cell that directly attacks infected cells. T regulatory: essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases.
What cell is HIV attacking when it replicated?
T-cells
Why is TB a big problem for AIDS patients?
TB is a particularly big problem for AIDS patients. T lymphocytes are destroyed in AIDS patients and they can't respond to the bacterial infection.
Differentiate TH1 and TH2 cells.
TH1: produces IFN-¥ which activates cells related to cell-mediated immunity, macrophages, and Abs. TH2: activate eosinophils and B cells to produce IgE.
Which is the T cell type that is generally involved in allergic reactions?
TH2
The initial stage of pertussis is called the ___________ stage and resembles ____________.
The initial stage of pertussis is called the catarrhal stage and resembles the common cold.
breakbone fever
The joint and muscle pain gives the patient the feeling that their bones are breaking
Differentiate the lymphatic and blood circulatory systems.
The main function of blood is to deliver oxygen and nutrients to tissues throughout the body, and carry away carbon dioxide and cellular waste (mostly lactic acid and calcium salts). Blood handles the day-to-day transport of living body materials. The lymphatic system, however, is meant to handle dangerous toxins and pathogens; a separate and parallel system to the circulatory system to transport materials too hazardous to be carried around in the bloodstream.
When there are serious local outbreaks of arboviral encephalitis, what is the usual response to minimize its transmission?
The most effective preventative measure is to control local mosquito populations.
How does the normal microbiota serve the respiratory tract?
The normal microbiota in the respiratory tract suppress pathogens by competitive inhibition in the upper respiratory system.
How has pertussis behaved in the USA?
The number of cases in the U.S. has been rising since 1981
Which of the following is greater? A) The number of reported cases of gonorrhea last year B) The number of reported cases of AIDS last year C) They are equal.
The number of reported cases of gonorrhea last year
Define epitope.
The part of an antigen molecule to which an antibody attaches itself.
Pseudomembrane colitis
The pathogen produces two toxins in the colon, an enterotoxin that causes watery diarrhea, and a cytotoxin that causes mucosal injury
Describe the pathodenicity of S. pyogenes.
The pathogenicity of S. pyogenes is enhanced by M protein, which helps it adhere to pharyngeal tissue and retard phagocytosis
The pathogenicity of S. pyogenes is enhanced by __________ , which helps it adhere to pharyngeal tissue and retard _____________.
The pathogenicity of S. pyogenes is enhanced by M protein, which helps it adhere to pharyngeal tissue and retard phagocytosis
Explain how a neutralization test works.
The presence of antibodies against a virus can be detected by the antibodies' ability to prevent cytopathic effects of viruses in cell cultures.
Define differential white blood cell count.
The proportions of the different types of white cells in the blood, usually split into the different types of granulocytes, lymphocytes, monocytes, eosinophils, and basophils.
Why does the reaction of a precipitation test become visible only in a narrow range?
The ratio of antigen-antibody has to be optimal.
29: Characteristics of the integumentary system
The skin, along with its accessory structures (nails, hair, sweat glands, and sebaceous glands 1. Sebaceous sites (forehead, back, and face) 2. Moist sites (navel, groin, sole of the foot, back of the knee, and inner elbow) 3. Dry sites (forearm, buttocks, and hand)
The vaccine DTaP contains __________ rather than ___________ to protect against the whooping cough.
The vaccine DTaP contains B. pertussis chemical extracts rather than killed cells to protect against the whooping cough.
What does Asymptomatic mean?
There are no symptoms and some people in this stage do not even know anything is wrong with them
How prevalent is diptheria in the USA?
There are usually less than a dozen confirmed cases in the U.S. each year.
What are some ways to treat AIDS?
There is no real treatment besides the presence of competitive blockers for virus binding sites on cells or virus proteins
Why does HIV attack T-cells?
They carry the CD4+ receptor which is what HIV needs to attach to the target cell
M protein
This protein is anchored in the cell wall and appears as fibrils protruding from the cell surface.
Trypansomiasis
Trypansomiasis (Chagas' Disease) Causative Organism: Trypansoma cruzi (flagellated protozoan) Transmission: -Arthropod vector- the REDUVIID BUG- called the "KISSING BUG"- it bites people near the lips -bitten human or animal often rubs the feces into the bite wound or other skin abrasions by scratching or into the eye by rubbing Reservoirs: - wide variety of wild animals- rodents, opossums, armadillos Symptoms: -acute stage: characterized by fever and swollen glands- lasting for a few weeks- may not cause alarm -20-30% of ppl infected will devlop a chronic form of the disease-in some cases 20 yrs later -Damage to nerves controlling the peristaltic contractions of the esophagus or colon can prevent them from transporting food -causes them to become grossly enlarged- conditions known as megaesophagus and megacolon Treatment: -Treating Chagas' disease- difficult when chronic, progressive stages have been reached -the trypanosome multiplies intracellularly and is difficult to reach chemotherapeutically -only drugs available are nifurtimox and benznidazole- which are triazole derivatives -Benznidazole therapy- found to eliminate infection in about 60% of infected children and is less toxic than nifurtimox -these drugs- must be administered for 30-60 days -neither is effective during chronic stage -both have serious side effects
How is one be tested for TB?
Tuberculin skin test (Mantoux test) can be used for early detection of TB exposure. It is followed by X-ray or CT exam, acid-fast staining of sputum, culturing of bacteria.
How much of the world population is infected with tuberculosis? How many die every year?
Tuberculosis is a major cause of death worldwide. One-third of the total population is infected, 2 million people die of TB every year, globally.
Urinary system
Two kidneys Two ureters One urinary bladder One urethra
The Female Reproductive System
Two ovaries Two uterine (fallopian) tubes The uterus, including the cervix; the vagina External genitals
21-1 Describe the structure of the skin and mucous membranes and the ways pathogens can invade the skin
Two parts; Dermis and Epidermis Passage ways for pathogens: Hair follicles, oil gland ducts, sweat gland ducts -Perspiration; Provides moisture and nutrients for bacterial growth -Sebum; A mixture of lipids, proteins and salts is secreted by oil glands to prevent skin and hair from drying out. Mucous Membranes -line the body cavities open to the exterior -Tightly packed epithelial cells attached to an extracellular matrix; cells secrete mucous; come cells have cilia -Often acidic, which limits the microbial population; normal flora produce fatty acids from sebum -Membrane of eyes washed by tears containing lysozyme, which destroys cell walls of certain bacteria -Often folded to maximize surface area
Male Reproductive System
Two testes Accessory glands Penis Epididymis Ductus (vas) deferens Ejaculatory duct Urethra
Explain how Western blotting works.
Used to identify a specific protein in a mixture. When protein is an antibody, the technique is valuable in diagnosing disease. Used commonly to confirm HIV infection. This protein seperation technique (sometimes called the protein immunoblot) is a widely used analytical technique used to detect specific proteins in the given sample of tissue homogenate or extract. It uses gel electrophoresis to separate native or denatured proteins by the length of the polypeptide (denaturing conditions) or by the 3-D structure of the protein (native/ non-denaturing conditions). The proteins are then transferred to a membrane (typically nitrocellulose or PVDF), where they are probed (detected) using antibodies specific to the target protein.
Explain why vaccination works
Vaccination process: -someone is vaccinated -B cells are activated and go through clonal selection -person is exposed to pathogen -antibodies are produced rapidly in response to pathogen. -antibodies produced by memory B cells initiate the destruction of pathogen -helps the body prepare in advance to find an illness; forces the body to produce antibodies and long term memory cells against the infection
List the antimicrobial features of the urinary system.
Valves that prevent backflow to kidneys Acidity of urine Mechanical flushing
On what part of the antibody molecule do we find the amino acid sequence that makes the huge genetic diversity of antibody production possible?
W/I Epitopes
Describe phagocyte migration.
W/I an hour of inflamation the phagocytes migrate to that cite. the sticking process in responce to local cytokines is called migration. the cytokines alter cellular adhesion molecules on cell linning blood vessels, causing phagocytes to stick to site of inflammation.
21-5 List the causative agents, modes of transmission, and symptoms of warts, smallpox, monkeypox, chickenpox, shingles, cold sores, measles, rubella, fifth disease, hand-foot-mouth disease, and roseola
Warts: Papillomas: small skin growths; transmitted via contact; caused by papillomarvirus; more than 50 types; some cause skin and cervical cancers; treated with cryotherapy, electrodesiccation, or salicylic acid Smallpox (Variola) -caused by an orthropoxvirus -two forms of the disease; Variola major has 20% mortality; Variola minor has <1% mortality -Transmitted via the respiratory route, moves into the blood stream, and infects the skin within 10 days -Completely eradicated from the human population by vaccination -No animal host reservoir -Potential bioterrorism agent Monkeypox -related to smallpox -endemic to small animals in africa -jumps from animals to humans -mortality of 1-10% -prevention by the smallpox vaccination -WHO monitors cases to see if human to human transmission increases Chicken Pox (Varicella) and Shingles (herpes zoster) -Herpesvirus varicella- zoster (human herpesvirus 3) -transmitted via the respiratory route -causes pus filled vesicles -Reye's Syndrome: severe complications of chickenpox; vomiting and brain dysfunction; asprin use increases risk -virus becomes latent in the central nerve ganglia where it hides from the immune system -prevented by a live attenuated vaccine; breakthrough varicella can occurs if previously vaccinated. Shingles (herpes zoster) -reactivation of the latent varicella-zoster virus that moves along peripheral nerves to the skin -due to stress or lowered immunity -follows the distribution of affected cutaneous sensory nerves -limited to one side of the body -prevention via the zoster vaccine -antiviral drugs may lessen symptoms Herpes Simplex -human herpesvirus 1 (HSV-1) and 2 (HSV-2) -HSV-1 is spread by oral or respiratory routes -HSV-2 is spread sexually 90% of the population is infected -Usually develop as cold sores or fever blisters -Not the cause of canker sores -HSV-1 remains in trigeminal nerve ganglia; outbreaks are triggered y the sun, stress, or hormonal changes HSV-2- remains latent in sacral nerve ganglia near the spine -Herepes gladiatorum: vesicles on the skin -Herpetic whitlow: vesicles in the fingers -Herpes encephalitis: virus spreads to the brain; rare; more severe form; treated with acyclovir Measles (Rubeola) -Viral disease transmitted by the respirtory route -Cold like symptoms, macular rash -Koplik's spots - red spots on the oral mucosa oppisite molars -Encephalitis (inflammation of the brain) in 1 in 1000 cases -Subacute sclerosing panecephalitis -rare; occurs 1-10 years after measles recovery -severe neurological symptoms resulting in death -prevented by the MMR (measles, mumps, rubella) vaccine -children under 1 year old do not receive the vaccine as it is not effective Rubella -german measles -rubella virus -macular rash and light fever -transmitted via the respiratory route; 2 to 3 week incubation -congenital rubella syndrome -fetal damage; deafness; heart defects; mental retardation; fifteen percent mortality -prevented by the MMR vaccine; not recommended for pregnant women
Universal Precautions
Wear gloves, gowns, masks, and goggles Do not recap needles Risk of infection from infected needlestick injury is 0.3%
What is another name for pertussis?
Whooping Cough
Types of Botulism
Wound botulism: is caused by toxins produced in the anaerobic tissue of a wound infected with C. botulinum. Can be treated with antibiotics. Infant botulism: results from the ingestion of soil or food contaminated with C. botulinum endospores. Endospores commonly found in honey. It affects mostly infants 3 to 24 months because they have not established the normal balance of bowel microbes. Treatment with the antitoxin reduces recovery time, and ventilation may be needed.
Trichomoniasis Organism
able to swim, has flagella like Giarrdia.
12) The material used in the pertussis vaccine consists of acellular chemical extracts of Bordetella pertussis. endotoxins treated with formaldehyde. bacterial pili. chemically altered exotoxins.
acellular chemical extracts of Bordetella pertussis.
Three phases of Kawasaki Syndrome
acute phase - begins with the abrupt onset of a high fever that is unresponsive to antibiotics and antipyretics - child then develops remaining diagnostic symptoms and is typically very irritable during this phase subacute phase -begins with resolution of the fever and lasts until all clinical signs of kawasaki disease have disappeared - child is at greatest risk for the development of coronary artery status during this phase - irritability persists convalescent phase - all clinical signs of kawasaki disease have resolved, but lab values have not returned to normal - this phase is complete when all blood values are normal (6 to 8 weeks after onset) - at the end of this stage, the child usually has regained his or her usual temperament, energy, and appetite
Recognize the clinical features of Kawasaki Syndrome.
acute systemic vasculitis of unknown cause with about 75% of the cases occurring in children younger than 5 years, with peak incidence in the toddler age group, acute disease is self-limiting important to be considered in any infant or child with prolonged elevated temperature that is unresponsive to antibiotics and not attributable to another cause
What is the derivation of the word adjuvant?
adjuvants: chemicals added to improve effectiveness of antigens; from adjuvare, meaning to help
*Define septicemia
an ACUTE illness associated w/ presence and persistence of PATHOGENIC MICROBES or their TOXINS in their BLOOD -Sepsis- defined as a systemic inflammatory response syndrome (SIRS) caused by a focus of infection that releases mediators of inflammation into the bloodstream -SIRS- must exhibit at least 2 of a set of defined conditions: -Fever, rapid heart, or respiratory rates, high count of WBCs. -if infective bacteria cause RBCs to lyse, the release of iron containing hemoglobin can result in accelerated microbial growth -sepsis and septicemia- often accompanied by appearance of lymphangitis- inflamed lymph vessels visible as red streaks under the skin running along the arm or leg from site of infection
Cystits
an infection of the bladder that is most often caused by E. coli.
Prostatitis
an inflammation and infection of the prostate that typically develops in young men or older men following the placement of a catheter.
Urethritis
an inflammation and infection of the urethra
Pyelonephritis
an inflammation of one or both kidneys Fever in the small of your back Causative agent: usually E. coli Symptoms: fever; back or flank pain Diagnosis: 10,000 CFU/ml and positive LE test Treatment: cephalosporin
Gastroenterics
an inflammation of the stomach and intestines, usually with vomiting and diarrhea. Such inflammations can arise from either intoxications or infections.
What is considered to be the most dangerous form of sexual contact for transmission of HIV? 19-29
anal-receptive
Retrovirus replication is a twist on what?
animal virus replication
What is the quick way to test for HIV?
antibody detection is the quick way to test for HIV
To be infective HIV must go through what steps?
attachment, fusion, and entry
Why is E. coli the most common cause of cystitis, especially in females?
because the bacteria can be transferred from the anal region tot he vaginal region with ease
Hematuria
blood in the urine
Bacillary Dysentery
bloody diarrhea
Scalded skin syndrome (staphylococcal)
bullous impetigo toxin B causes exfoliation pemphigus neonatorum: impetigo of the newborn
How is HIV spread?
by dendritic cells
Identify the role of the cardiovascular and lymphatic systems in spreading and eliminating infections.
circulates blood through the body's tissues Includes the heart and associated arteries, veins, and capillaries Delivers substances to and removes substances from the cells
Hepatocellular carcinoma (HCC)
cirrhosis of the liver may result. Carriers are also at an increased risk
Group A streptococcus
contain pathogenic organisms, such as Streptococcus pyogenes.
Gastrointestinal tract
contains digestive organs (oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine).
Staph. aureus
carried in nasal passages of 20% of pool golden-yellow coagulase(+) may produce damaging toxins & cause sepsis avoids host defenses in skin by secreting proteins & toxins that kill phagocytic cells MRSA strains are antibiotic-resistant
List the causative agents, symptoms, methods of diagnosis, and treatments for nongonococcal urethritis (NGU)
causative agents: Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum Symptoms: Painful urination and watery discharge; in women, possible complications, such as PID Diagnosis: Culturing, PCR Treatment: Doxycycline, azithromycin
Streptococcus pneumoniae
cause S. pneumoniae (Gram Positive diplococcus) 70% of people are healthy nasopharyngeal carriers Most common in children (1 month - 4 years) Mortality is 30% in children and 80% in elderly Prevented by vaccination
smallpox (variola)
cause by orthopoxvirus Forms: 1. variola major 20% mortality 2. variola minor <1% transmitted: resp → bloodstream → skin *monkeypox: smallpox, endemic to sm animal in Africa; animals → humans; mortality: 1-10%;
Cytomegalovirus
causes brain damage and mental retardation, a type of herpes.
Dysbiosis
changes on the composition of microbiota, helps us to understand how the gut microbiome contributes to the development of other diseases.
Hemorrhagic colitis
characterized by bloody diarrhea, abdominal cramps, and a mild fever.
nonparalytic poliomyelitis vs paralytic poliomyelitis
characterized by fever, headache, and stiff neck. Complete recovery usually occurs. the virus infects the brain. This results in paralysis of the arms, legs, and body trunk.
Pertussis is primarily a (childhood/adulthood) disease, but can be quite severe
childhood
7) The presence of a psudomembrane is a result of strep throat meningitis diphtheria scarlet fever tuberculosis
diphtheria
16) Bacteriophages have been located in a lysogenic relationship with the causative organisms of pertussis and Q fever. tuberculosis and pneumococcal pneumonia. psittacosis and Q fever. diphtheria and scarlet fever.
diphtheria and scarlet fever.
17) The organisms of tetanus and ______ are known for their production of _______. pertussis; antitoxins typhoid fever; exotoxins tetanus; antitoxins diphtheria; exotoxins
diphtheria; exotoxins
Downey cells
damaged B cells with granulated and abundant cytoplasm
Alpha toxin
damages the plasma membranes and disrupts cell tissues, facilitating the spread of bacterial cells into the blood (sepsis)
SUMMARY! Introduction
• 1. The heart, blood, and blood vessels make up the cardiovascular system. • 2. Lymph, lymph vessels, lymph nodes, and lymphoid organs constitute the lymphatic system.
*Why are certain foods more likely than others to cause Staphylococcal food poisoning?
high-risk foods (custards, cream pies, hams) -These foods are considered high risk because of the high osmotic pressure of sugars, which minimize the competing microbes. Cooking also minimizes the competing microbes. --> therefore, staph can grow more easily as there are no other competing microbes for nutrients. -Poultry- can harbor staph if handled and allowed to stand at room temp -Hamburger- staph do not compete well w/ large # of microbes that hamburger contains- its RARELY a factor in this type of food poisoning -foods prepared in advanced that are not kept chilled- source of staphylococcal food poisoning
Intoxications
illnesses in which bacterial toxins are ingested in food or water.
The latent infection is stored where?
in vacuoles
Where is the latent infection?
in vacuoles and t-cells
*Explain the unique form of persistence of anthrax in some areas.
incidence of human anthrax- rare in US, but occurrence in grazing animals is not uncommon -ppl at risk: those who handle animals, hides, wool and other animal products from foreign countries -Bacillus anthracis- causes anthrax in animals -endospore-forming bacillus -large, aerobic, gram-positive microbe that is able to grow slowly in soil types having specific moisture conditons -endospores have survived in tests in soil for up to 60 yrs -disease strikes primarily grazing animals- cattle and sheep -endospores are ingested along w/ grasses, causing a fulminating, fatal sepsis
What is a Candida albican?
infection of mouth, throat, or vaginia
folliculitis (staphylococcal)
infections of hair follicles *sty: folliculitis of an eyelash
Oncogenic (tumor causing) viruses
influence cancer development,transferred to test animals or cultures, an observable change in the morphology, biochemical, or growth patterns of normal cells takes place.
5) The exotoxin of Corynebacterium diphtheriae destroys Krebs cycle enzymes in tissues. interferes with ATP production in infected tissues. inhibits protein synthesis. interferes with membrane transport in human cells only.
inhibits protein synthesis.
What is the most common mode, worldwide, by which HIV is transmitted? 19-30
injected drugs
20.) Bordetella pertussis causes wooping cough by interfering with the activity of ciliated epithelial cells in the trachea the development of pneumonia suppressing mucus production forming a psudomembrane that obstructs the respiratory passages
interfering with the activity of ciliated epithelial cells in the trachea
What are the seven different routes of HIV transmission?
intimate sexual contact breast milk transplacental infection of a fetus blood-contaminated needles organ transplants artificial insemination blood transfusion
Characteristics of different types of anthrax
is a enzootic disease caused by Bacillus anthracis because it often infects large, domestic herbivores, such as cattle, sheep, and goats. The animals graze and ingest spores, which germinate inside the animal.Humans acquire anthrax from the infected animal in one of three ways: inhalation, intestinal, and cutaneous
Plasma viral load (PVL)
is determined by PCR or nucleic acid hybridization
Names three antibiotics used to treat TB.
isoniazid, rifampin, and pyrazinamide
What does the DNA do now that it is in the host cell?
it can control the production of an active infection or remains hidden in the host cell as a provirus
Congenital rubella syndroma
it can lead to destruction of the fetal capillaries, and blood insufficiency follows. The organs most affected include the eyes, ears, and cardiovascular organs, and children may be born with cataracts, glaucoma, deafness, or heart defects
What are the three components of the structure of HIV?
it has two identical strands of RNA the enzyme reverse transcriptase phospholipid envelope
What is reverse transcriptase?
it is where RNA is released and is transcribed into DNA.
2) All of the following are true statements concerning tuberculosis EXCEPT because of the waxy cell walls, TB bacteria can survive for months in dry sputum only about 3-10 cells are required for infection the disease may be arrested if the early tubercles become calcified extremely dangerous multiple drug-resistant strains have emerged it occurs only in the lungs
it occurs only in the lungs
33: Infectious mononucleosis
kissing disease" because it is spread from person-to-person via saliva or saliva contaminated objects.
A vaccine against AIDS must do what?
must elicit cell-mutated immunity as well as humoral immunity
Buruli ulcer
mycobacterium ulcers: produces toxin mycolactone *enters via break in skin or insect bite *causes deep damaging ulcers → may require amputation *exceeds incidence of leprosy: 1º western & central Africa
Would an antibody against the coat of HIV be able to react with a provirus?
no because the provirus shelters it from the immune system
Elementary body
non-replicating, extracellular, infectious
Sylvatic (jungle) yellow fever
occurs in monkeys and other jungle animals, where the yellow fever virus is taken up by blood-feeding mosquitos.
Accessory digestive organs
outgrowths connected to the GI tract including salivary glands, liver, gallbladder, and pancreas. They are generally sterile.
warts
papillomas: sm skin growths transmission: contact papillomavirus: some cervical cancer treat: cryotherapy, electrodesiccation or salicylic acid
Fxn of skin (Cont)
perspiration provides moisture & nutrients for growth → contains salt that inhibits MO lysozyme bkdn bacterial cell walls anti-MO peptides sebum secreted by oil glands contain FA (inhibit pathogens)
25: Shiga toxin
produce enterotoxins
pustules (papules)
raised lesions w/ pus
13) A paroxysm is a __________ and is characteristic of _________. fever; meningitidis rapid-fire cough; meningitis fever; pneumonia headache; pertussis rapid-fire cough; pertussis
rapid-fire cough; pertussis
enanthem
rash on mucous membranes arising from disease
shingles (herpes-zoster)
reactivation of latent varicella-zoster virus that moves along peripheral nerve to skin → stress, lowered immunity follows distribution of affected cutaneous sensory nerves postherpetic neuralgia prevention: zoster vaccine antiviral drugs may lessen symptoms
1)The diagnosis of tuberculosis is aided by observation of cells with bipolar staining in the blood. recovery of acid-fast rods from the sputum. an agglutination cold test. "fried egg" shaped colonies on agar
recovery of acid-fast rods from the sputum
32: Koplik spots
red patches with white grain-like centers
Infections
refer to illnesses in which live bacterial pathogens in food and water are ingested and subsequently grow in the body.
Differentiate physical from chemical factors, and list five examples of each.
~ Physical factors: 1) Skin: Epidermis consists of tightly packed cells with Keratin, a protective protein 2) Mucous membranes: Line the GI, respiratory and genitourinary tracts 3)Secrete Mucus (produced by goblet cells): traps microbes 4)Keeps moisture 5) Lacrimal apparatus: washes eye 6) Saliva: washes microbes off 7) Urine: flows out 8) Vaginal secretions: flow out 9) Earwax: protects ear drum ~ Chemical Factors Sebum: oily substance made from sebaceous glands of the skin 1) Fungistatic fatty acid in sebum 2) Low pH (3-5) of skin 3) Lysozyme (cleave cell wall of bacteria) in perspiration, tears, saliva, and urine 4) Low pH (1.2-3.0) of gastric juice 5) Low pH (3-5) of vaginal secretions
Explain how precipitation reactions and immunodiffusion tests work.
~ Precipitation Reactions: IgM or IgG + antigens = lattices, precipitation ring test = antigen rich sol'n placed atop antibody rich sol'n, where they touch a precipitate layer forms ~ Immunodiffusion test: tests carried out an agar plate
Differentiate precipitation from neutralization tests.
~ Precipitation test: Relies on fact that antigens and antibody mixed in the proper proportion form large macromolecular complexes called precipitates. - Correct proportions are important to create precipitation. - One of the easiest of serological tests. ~ Neutralization test: Ability of virus to kill culture cells is neutralized when virus is first mixed with antibodies against it.
Differentiate sensitivity from specificity in a diagnostic test.
~ Sensitivity: Probability that the test is reactive if the specimen is a true positive. ~ Specificity: Probability that a positive test will not be reactive if a specimen is a true negative.
Compare and contrast T-dependent and T-independent antigens.
~ T-dependent antigens - Ag presented with (self) MHC to TH cell. - TH cell produces cytokines that activate the B cell. ~ T-independent antigens - Stimulate the B cell to make Abs.
Describe the roles of vasodilation, kinins, prostaglandins, and leukotrienes in inflammation.
~ Vasodilation: dilation of clood vessels to increase blood flow to the damaged area and is responsible for the redness associated with inflammation ~ Kinins: another group of substances that cause vasodialation and increased permeability of blood vessels ~ Prostaglandins: substances released by damaged cells intensify the effects of histamine and kinins and help phagocytes move through the capillary walls ~ Leukotrienes: produced by mast cells that cause increased permeability of blood vessels and help attach phagocytes to pathogens
Classify leukocytes, and describe the roles of granulocytes and monocytes.
~ White blood cells: Destroy target cells by perforins proteins that cause cytolysis and granzymes that cause target cells to undergo apoptosis. ~ Granulocytes: a type of WBC (can be seen when stained) active in initial stage of infection, allergy responses, produce toxins against parasites. ~ Monocyte: type of WBCn (phagocytosis when they mature into macrophages) precurser of a macrophage.
What is the production of whole-agent vaccines?
~ Whole-agent Vaccine: - Living Agent, usually virus - Agent usually reproduces in host, therefore, generally provides most effective and long-lived immunity. - Microbe is either avirulent or less virulent than the disease-causing agent - Risk of Back mutation ~ Recombinant vaccines:
Differentiate the following, and provide an example of each: attenuated, inactivated, toxoid, subunit, and conjugated vaccines.
~ attenuated: Live microorganisms used, life lone immunity-MMR. ~ inactivated: killed microorganism by toxin- rabies, polio vaccine ~ toxoid: inactivated toxin-tetanus. ~ subunit: antigen without a viral particle. antigenic fragments of a microorganism that best stimulate an immune response-recombinant B hepatitis, and pneumococcal pneumonia vax ~ conjugated: bacterial capsular polysaccharide joined to a protein to enhance immunogenicity-deals with children with poor immune systems or HIB vaccine
Distinguish a primary from a secondary immune response.
~ primary: response of the body to the first contact with an antigen. ~ secondary: second contact with the same antigen results in a much higher antibody concentration (titer), also called anamnestic or memory response.
Differentiate humoral from cellular immunity.
~Humoral immunity -B cells mature in the bone marrow *Chickens: Bursa of Fabricius - Due to antibodies ~Cellular immunity - Due to T cells - T cells mature in the thymus (T and B cells develop from stem cells in red bone marrow)
Contrast subunit vaccines and nucleic acid vaccines.
~Subunit vaccine a vaccine produced from specific protein subunits of a virus and thus having less risk of adverse reactions than whole virus vaccines. ~ Nucleic acid vaccine-immunization that elicits immune responses similar to those induced by live, attenuated vaccines.
Streptococci can be divided into three groups, based on how they affect sheep red blood cells. Name and describe those groups.
α-hemolytic. Partial lysis. Blood agar turns olive green ß-hemolytic. Complete lysis. Clear, colorless zones. γ-hemolytic. No change in the agar. No lysis of red blood cells
Bacterial Diseases of the Lower Digestive System
• 1. A gastrointestinal infection is caused by the growth of a pathogen in the intestines. • 2. Incubation times range from 12 hours to 2 weeks. Symptoms of infection generally include a fever. • 3. A bacterial intoxication results from ingesting preformed bacterial toxins. • 4. Symptoms appear 1 to 48 hours after ingestion of the toxin. Fever is not usually a symptom of intoxication. • 5. Infections and intoxications cause diarrhea, dysentery, or gastroenteritis. • 6. These conditions are usually treated with fluid and electrolyte replacement.
Bacterial Diseases of the Mouth Dental Caries (Tooth Decay)
• 1. Dental caries begin when tooth enamel and dentin are eroded and the pulp is exposed to bacterial infection. • 2. Streptococcus mutans, found in the mouth, uses sucrose to form dextran from glucose and lactic acid from fructose. • 3. Bacteria adhere to teeth by the sticky dextran, forming dental plaque. • 4. Acid produced during carbohydrate fermentation destroys tooth enamel at the site of the plaque. • 5. Gram-positive rods and filamentous bacteria can penetrate into dentin and pulp. • 6. Carbohydrates such as starch, mannitol, sorbitol, and xylitol are not used by cariogenic bacteria to produce dextran and do not promote tooth decay. • 7. Caries are prevented by restricting the ingestion of sucrose and by the physical removal of plaque.
Introduction
• 1. Diseases of the digestive system are the second most common illnesses in the United States. • 2. Diseases of the digestive system usually result from ingesting microorganisms or their toxins in food and water. • 3. The fecal-oral cycle of transmission can be broken by the proper disposal of sewage, the disinfection of drinking water, and proper food preparation and storage.
Viral Diseases of the Cardiovascular and Lymphatic Systems Burkitt's Lymphoma
• 1. Epstein-Barr virus (EB virus, HHV-4) causes Burkitt's lymphoma. • 2. Burkitt's lymphoma tends to occur in patients whose immune system has been weakened; for example, by malaria or AIDS.
Protozoan Diseases of the Digestive System Giardiasis
• 1. Giardia lamblia grows in the intestines of humans and wild animals and is transmitted in contaminated water. • 2. Symptoms of giardiasis are malaise, nausea, flatulence, weakness, and abdominal cramps that persist for weeks.
Normal Microbiota of the Digestive System
• 1. Large numbers of bacteria colonize the mouth. • 2. The stomach and small intestine have few resident microorganisms. • 3. Bacteria in the large intestine assist in degrading food and synthesizing vitamins. • 4. Up to 40% of fecal mass is microbial cells.
Viral Diseases of the Digestive System Mumps
• 1. Mumps virus enters and exits the body through the respiratory tract. • 2. About 16 to 18 days after exposure, the virus causes inflammation of the parotid glands, fever, and pain during swallowing. About 4 to 7 days later, orchitis may occur. • 3. After onset of the symptoms, the virus is found in the blood, saliva, and urine. • 4. A measles, mumps, rubella (MMR) vaccine is available.
Fungal Diseases of the Digestive System
• 1. Mycotoxins are toxins produced by some fungi. • 2. Mycotoxins affect the blood, nervous system, kidneys, or liver.
Bacterial Diseases of the Cardiovascular and Lymphatic Systems Sepsis and Septic Shock
• 1. Sepsis is an inflammatory response caused by the spread of bacteria or their toxin from a focus of infection. Septicemia is sepsis that involves proliferation of pathogens in the blood. • 2. Gram-negative sepsis can lead to septic shock, characterized by decreased blood pressure. Endotoxin causes the symptoms. • 3. Antibiotic-resistant enterococci and group B streptococci cause gram-positive sepsis. • 4. Puerperal sepsis begins as an infection of the uterus following childbirth or abortion; it can progress to peritonitis or septicemia. • 5. Streptococcus pyogenes is the most frequent cause of puerperal sepsis. • 6. Oliver Wendell Holmes and Ignaz Semmelweiss demonstrated that puerperal sepsis was transmitted by the hands and instruments of midwives and physicians.
Structure and Function of the Digestive System
• 1. The gastrointestinal (GI) tract, or alimentary canal, consists of the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. • 2. In the GI tract, with mechanical and chemical help from the accessory structures, large food molecules are broken down into smaller molecules that can be transported by blood or lymph to cells. • 3. Feces, the solids resulting from digestion, are eliminated through the anus. • 4. GALT is part of the immune system.
Structure and Function of the Cardiovascular and Lymphatic Systems
• 1. The heart circulates substances to and from tissue cells. • 2. Blood is a mixture of plasma and cells. • 3. Plasma transports dissolved substances. Red blood cells carry oxygen. White blood cells are involved in the body's defense against infection. • 4. Fluid that filters out of capillaries into spaces between tissue cells is called interstitial fluid. • 5. Interstitial fluid enters lymph capillaries and is called lymph; vessels called lymphatics return lymph to the blood. • 6. Lymph nodes contain fixed macrophages, B cells, and T cells.
Classic Viral Hemorrhagic Fevers
• 13. Yellow fever is caused by the yellow fever virus. The vector is the Aedes aegypti mosquito. • 14. Signs and symptoms include fever, chills, headache, nausea, and jaundice. • 15. Diagnosis is based on the presence of virus-neutralizing antibodies in the host. • 16. No treatment is available, but there is an attenuated, live viral vaccine. • 17. Dengue is caused by the dengue fever virus and is transmitted by the Aedesmosquito. • 18. Signs are fever, muscle and joint pain, and rash. • 19. Mosquito abatement is necessary to control the disease. • 20. Dengue hemorrhagic fever (DHF) can cause shock.
Rheumatic Fever
• 14. Rheumatic fever is an autoimmune complication of streptococcal infections. • 15. Rheumatic fever is expressed as arthritis or inflammation of the heart. It can result in permanent heart damage. • 16. Antibodies against group A beta-hemolytic streptococci react with streptococcal antigens deposited in joints or heart valves or cross-react with the heart muscle. • 17. Rheumatic fever can follow a streptococcal infection, such as streptococcal sore throat. Streptococci might not be present at the time of rheumatic fever. • 18. Prompt treatment of streptococcal infections can reduce the incidence of rheumatic fever. • 19. Penicillin is administered as a preventive measure against subsequent streptococcal infections.
Salmonellosis (Salmonella Gastroenteritis)
• 14. Salmonellosis, or Salmonella gastroenteritis, is caused by many Salmonella entericaserovars. • 15. Symptoms include nausea, abdominal pain, and diarrhea and begin 12 to 36 hours after eating large numbers of Salmonella. Septic shock can occur in infants and in the elderly. • 16. Mortality is lower than 1%, and recovery can result in a carrier state. • 17. Cooking food will usually kill Salmonella.
Typhoid Fever
• 18. Salmonella typhi causes typhoid fever; the bacteria are transmitted by contact with human feces. • 19. Fever and malaise occur after a 2-week incubation period. Symptoms last 2 to 3 weeks. • 20. S. typhi is harbored in the gallbladder of carriers. • 21. Typhoid fever is treated with quinolones and cephalosporins; vaccines are available for high-risk people.
Toxoplasmosis
• 2. Toxoplasmosis is caused by Toxoplasma gondii. • 3. T. gondii undergoes sexual reproduction in the intestinal tract of domestic cats, and oocysts are eliminated in cat feces. • 4. In the host cell, sporozoites reproduce to form either tissue-invading tachyzoites or bradyzoites. • 5. Humans contract the infection by ingesting tachyzoites or tissue cysts in undercooked meat from an infected animal or contact with cat feces. • 6. Congenital infections can occur. Signs and symptoms include severe brain damage or vision problems.
Tularemia
• 20. Tularemia is caused by Francisella tularensis. The reservoir is small wild mammals, especially rabbits. • 21. Signs include ulceration at the site of entry, followed by septicemia and pneumonia.
Emerging Viral Hemorrhagic Fevers
• 21. Human diseases caused by Marburg, Ebola, and Lassa fever viruses were first noticed in the late 1960s. • 22. Ebola virus is found in fruit bats; Lassa fever viruses are found in rodents. Rodents are the reservoirs for Argentine and Bolivian hemorrhagic fevers. • 23. Hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome are caused by Hantavirus. The virus is contracted by inhalation of dried rodent urine and feces.
Brucellosis (Undulant Fever)
• 22. Brucellosis can be caused by Brucella abortus, B. melitensis, and B. suis. • 23. The bacteria enter through minute breaks in the mucosa or skin, reproduce in macrophages, and spread via lymphatics to liver, spleen, or bone marrow. • 24. Signs include malaise and fever that spikes each evening (undulant fever). • 25. Diagnosis is based on serological tests.
Cholera
• 22. Vibrio cholerae O:1 and O:139 produce an exotoxin that alters the membrane permeability of the intestinal mucosa; the resulting vomiting and diarrhea cause loss of body fluids. • 23. The symptoms last for a few days. Untreated cholera has a 50% mortality rate.
Noncholera Vibrios
• 24. Ingestion of other V. cholerae serotypes can result in mild diarrhea. • 25. Vibrio gastroenteritis can be caused by V. parahaemolyticus and V. vulnificus. • 26. These diseases are contracted by eating contaminated crustaceans or contaminated mollusks.
Anthrax
• 26. Bacillus anthracis causes anthrax. In soil, endospores can survive for up to 60 years. • 27. Grazing animals acquire an infection after ingesting the endospores. • 28. Humans contract anthrax by handling hides from infected animals. The endospores enter through cuts in the skin, respiratory tract, or mouth. • 29. Entry through the skin results in a pustule that can progress to sepsis. Entry through the respiratory tract can result in septic shock. • 30. Diagnosis is based on isolating and identifying the bacteria.
Escherichia coli Gastroenteritis
• 27. Enterotoxigenic, enteroinvasive and enteroaggregative, strains of E. coli cause diarrhea. • 28. Enterohemorrhagic E. coli, such as E. coli O157:H7, produces Shiga toxins that cause inflammation and bleeding of the colon, including hemorrhagic colitis and hemolytic uremic syndrome. • 29. The most common causes of traveler's diarrhea are enterotoxigenic and enteroaggregative E. coli.
Cryptosporidiosis
• 3. Crytosporidium spp. cause diarrhea; in immunosuppressed patients, the disease is prolonged for months. • 4. The pathogen is transmitted in contaminated water.
Ergot Poisoning
• 3. Ergot poisoning, or ergotism, is caused by the mycotoxin produced by Claviceps purpurea. • 4. Cereal grains are the crop most often contaminated with the Claviceps mycotoxin.
Infectious Mononucleosis
• 3. Infectious mononucleosis is caused by EB virus. • 4. The virus multiplies in the parotid glands and is present in saliva. It causes the proliferation of atypical lymphocytes. • 5. The disease is transmitted by the ingestion of saliva from infected individuals. • 6. Diagnosis is made by an indirect fluorescent-antibody technique. • 7. EB virus may cause other diseases, including cancers and multiple sclerosis.
Campylobacter Gastroenteritis
• 30. Campylobacter is the second most common cause of diarrhea in the United States. • 31. Campylobacter is transmitted in cow's milk.
Hepatitis
• 5. Inflammation of the liver is called hepatitis. Symptoms include loss of appetite, malaise, fever, and jaundice. • 6. Viral causes of hepatitis include hepatitis viruses, Epstein-Barr virus (EBV), and cytomegalovirus (CMV). • 7. Hepatitis A virus (HAV) causes hepatitis A; at least 50% of all cases are subclinical. • 8. Hepatitis B virus (HBV) causes hepatitis B, which is frequently serious. • 9. Hepatitis C virus (HCV) is transmitted via blood. • 10. Hepatitis D virus (HDV) has a circular strand of RNA and uses HBsAg as a coat. • 11. Hepatitis E virus (HEV) is spread by the fecal-oral route. • 12. There is evidence of the existence of hepatitis types F and G.
Amebic Dysentery (Amebiasis)
• 7. Amebic dysentery is caused by Entamoeba histolytica growing in the large intestine. • 8. The ameba feeds on red blood cells and GI tract tissues. Severe infections result in abscesses.
Staphylococcal Food Poisoning (Staphylococcal Enterotoxicosis)
• 7. Staphylococcal food poisoning is caused by the ingestion of an enterotoxin produced in improperly stored foods. • 8. S. aureus is inoculated into foods during preparation. The bacteria grow and produce enterotoxin in food stored at room temperature. • 9. Boiling for 30 minutes is not sufficient to denature the exotoxin. • 10. Foods with high osmotic pressure and those not cooked immediately before consumption are most often the source of staphylococcal enterotoxicosis. • 11. Laboratory identification of S. aureus isolated from foods is used to trace the source of contamination.
Bacterial Infections of the Heart
• 7. The inner layer of the heart is the endocardium. • 8. Subacute bacterial endocarditis is usually caused by alpha-hemolytic streptococci, staphylococci, or enterococci. • 9. The infection arises from a focus of infection, such as a tooth extraction. • 10. Preexisting heart abnormalities are predisposing factors. • 11. Signs include fever, anemia, and heart murmur. • 12. Acute bacterial endocarditis is usually caused by Staphylococcus aureus. • 13. The bacteria cause rapid destruction of heart valves.
Malaria
• 7. The signs and symptoms of malaria are chills, fever, vomiting, and headache, which occur at intervals of 2 to 3 days. • 8. Malaria is transmitted by Anopheles mosquitoes. The causative agent is any one of four species of Plasmodium. • 9. Sporozoites reproduce in the liver and release merozoites into the bloodstream, where they infect red blood cells and produce more merozoites.
Cytomegalovirus Infections
• 8. CMV (HHV-5) causes intranuclear inclusion bodies and cytomegaly of host cells. • 9. CMV is transmitted by saliva and other body fluids. • 10. CMV inclusion disease can be asymptomatic, a mild disease, or progressive and fatal. Immunosuppressed patients may develop pneumonia. • 11. If the virus crosses the placenta, it can cause congenital infection of the fetus, resulting in impaired mental development, neurological damage, and stillbirth.
Periodontal Disease
• 8. Caries of the cementum and gingivitis are caused by streptococci, actinomycetes, and anaerobic gram-negative bacteria. • 9. Chronic gum disease (periodontitis) can cause bone destruction and tooth loss; periodontitis is due to an inflammatory response to a variety of bacteria growing on the gums. • 10. Acute necrotizing ulcerative gingivitis is often caused by Prevotella intermedia.
