fml fml fml
A 45-year-old man has pus-filled vesicles distributed over his back in the upper right quadrant, over his right shoulder, and upper right quadrant of his chest. His symptoms are most likely due to
varicella-zoster virus.
HCV
hepatitis C virus
HDV
hepatitis D virus
HEV
hepatitis E virus
Which of the following is caused by an opportunistic pathogen?
candidiasis
HPV
(Human Papillomavirus) a virus that can cause genital warts, cervical cancer, or be asymptomatic
Eosinophils
*What IgE-mediated cell secretes major basic protein and has elevated levels in the blood during asthma and parasitic infections? *What type of WBC is present in increased numbers during an allergic reaction?
basophils
*When performing a WBC differential, which cell has the large, scattered dark blue granules that are darker than the nucleus? *A circulating leukocyte that produces histamine.
SARS-CoV-2 is the Cause of COVID-19
- A novel human coronavirus emerged in Wuhan, China in November 2019, causing severe respiratory disease in humans. -Chinese identified and sequenced the genetic material of this virus -It is a positive-sense, envelope RNA virus related to other coronaviruses of previous outbreaks -SARS coronavirus (2003), that cause of Severe Acute Respiratory Syndrome, mostly confined to China and SE Asia -MERS-CoV outbreak (2012), a servere outbreak of repriatory disease in the Middle East and South Korea.
Major Viral STIs
- AIDS, caused by HIV infection -Cervical cancer, caused by HPV -Genital warts, also caused by HPV, is most common ST in the US today -A vaccine in available -Cytomegalovirus infection, caused by CMV -Body fluids, sexual transmission, congenital. -Hepatitis B, caused by HBV - a vaccine is available.
Measles Complications
- Frequent pneumonia -Encephalitis in 1 in 1,000 cases -Subacute sclerosing panecephalitis in 1 in 100,000 cases -Measles is prevented by the MMR vaccine -MEASLES, MUMPS AND RUBELLA
Pertussis or Whooping Cough (Bordetella pertussis)
- Gram-negative encapsulated coccobacillus -Tracheal cytotoxin (TCT) damage ciliated cells -Another toxin, Pertussis toxin (PT) is an AB-type exotoxin -Endemic in the US despite vaccination -Thousands of cases in the last few years -Prevent by DTaP vaccine (acellular Pertussis cell fragments) -Vaccine immunity seems to wane
Viral Diseases of the Skin: Warts
- Harmless growth caused by HPV infections - Genital warts are STI's -In hands and feet, face, genitals Treatment - Removal - Cryotherapy -Electrodesiccation -Salicylic acid - Imiquimod (Stimulates interferon production) - Bleomycin
Streptococcal Toxic Shock Syndrome
- M proteins complex with fibrinogen - Bind to neutrophils - Activate neutrophils - Release of damaging enzymes - Shock and organ damage
Microbes and the Nervous System
- No microbe: normal microbiota of the central nervous system -Meningitis: Inflammation of meninges -Encephalitis: Inflammation of the brain -Meningoencephalitis: Inflammation of both the meninges and the brains
Prevention of Rabies
- Preexposure prophylaxis: injection of human diploid cells vaccine (HDCV) - Postexposure treatment: vaccine plus rabies immune globulin (RIG)
Shingles
- Reactivation of latent HHV-3 releases viruses that move along peripheral nerves to skin -Postherpetic neuralgia -Prevention: Live attenuated vaccine - Valacyclovir (nulcleoside analog) may lessen symptoms
COVID-19
-According to the CDC, the novel coronavirus may cause: -cough -shortness of breath or diffuclty breathing -fever -chills -repeated shaking with chills -muscle pain -headache -sore throat -new loss of taste or smeel
Claire is a healthy 19 year-old college freshman enjoying her first few weeks of being on a college campus. She's made lots of new friends, has been participating in many of the on-campus outdoor social activities, and is getting used to a hectic class schedule. For the last couple of days, she's been feeling more tired than usual, and she's had a sore throat. Her sore throat has been worsening, and she also has a low-grade fever and a headache that has been getting worse throughout the day. Although Claire thinks that her symptoms are due to exhaustion, Claire's roommate urges her to go the student health center just to make sure that it's nothing too major. At the student health center, Claire is examined by Dr. Peterson. She takes a routine medical history and does some basic assessment of Claire's condition including listening to her heart and lungs, checking her ears and eyes (for light responsiveness), looking at her throat, and feeling the lymph nodes in Claire's neck. Claire expects that Dr. Peterson is going to tell her to go home, drink plenty of liquids, and get lots of rest and that she'll be back to normal in a couple of days. Instead, Claire is surprised when Dr. Peterson tells her that there have been a couple of cases of meningitis reported in students living in Claire's dorm and she would like to do further tests for meningitis. Claire informs Dr. Peterson that she has received the vaccine for meningitis. Although Dr. Peterson tells Claire that this is a good thing, she informs Claire that they need to conduct further tests to confirm the causative agent and proceed with treatment.
----
S.A.R. (Severe Acute Respiratory Syndrome)
-2003: A new viral pneumonia affected 8,000 people in 20 countries, 10 % mortality. A few cases in the US -A coronavirus (SAR-CoV), an RNA, enveloped virus, was found to be responsible for the disease -Transmitted from droplets from infected people, possibly airborne. Related to worldwide transorptation
Tuberculous (Mycobacterium tuberculosis)
-Acid-fast cell wall bacteria; transmitted personn-to-person -Urease-positive aerobic bacillus -Other tuberculosis pahogen are M.bovis (non-human) and M. avium-intracellulare complex that infects people with late-stage HIV infections -Currently, low incidence in the US
Hepatitis
-An inflammation of the liver -May result from drug or chemical toxicity, EB virus, CMV or the hepatitis virus
Virulence Factors of Staphylococcus aureus
-Antibiotic resistant -Resists opsonization -Survives in phagolysosome -Lysozyme resistant -Produces leukocidin and other membrane-damaging proteins -Bioflims -Exotoxins Enterotoxin, Exfoliative toxin, Superantigen:TSS1
Characteristics of the COVID-19 Pandemic
-As of 5/2020, 3M cases,> 220,000 fatalities -In the US, > 1M cases, 60,000 deaths -Older adults and people with severe heath issues more at risk -Disease transmitted by respiratory droplets and contaminated objects -Incubation Period: 2 to 14 days -Severe disease caused by reaction of the immune system to the presence of the virus in the body -No specific treatment, no vaccine, many ongoing clinical trials of vaccine candidates and medicines
Genital Herpes
-Caused by herpes simplex virus 2 (human herpevirus 2, HHV-2; previously known as HSV-3) -Painful vesicles on genital,but frequently no symptoms -Transmission by intimate sexual contact, from a visible blister or just an infected partner. -Neonate herpes transmitted to fetus or newborns - Recurrences from viruses latent in nerves -suppression: acyclovir - nucleoside analog, inhibitor of viral DNA polymerase
Rabies
-Caused by the rabies virus -Transmitted by animal bite -Wild and domestic beasts -Furious rabies: Animals are restless then highly excitable -Paralytic rabies: Animal seem unaware of surroundings
Listeriosis (listeria moncytogenes)
-Currently, responsible for higher mortality than C. botulinum and Salmonella -Gram-positive motile aerobic rod -Reproduuce in phagocytes -Mobilize cell-to-cell by actin rockets -Usually foodborne (meats, cold cuts, unpasteurized milk); it can by transmitted to fetus -Gastroenteritis, meningoencephalitis, miscarriage, stillbirth
Haemophilus influenzae pneumonia
-Gram-negative coccobacillus Predisposing factors: alcoholism, poor nutrition, cancer or diabetes Diagnosis: isolation; special media for nutritional requirments Treatment: Cephalosporins
Salmonella
-Gram-negative, facultative anaerobic motile rods, enterobacteria close relative of E. coli. -Bacteria spread throughout body in phagocytes -Can reach bloodsteam and cause septic shock -Birds, reptiles are reservoirs
Gram-Positive Sepsis
-Healthcare-associated infections staphylococcus aureus streptococcus pyogenes Groupe B streptococcus, Steptococcus agalactiae Enterococcus faecium and Enterococcus faecalis
The Influenza Virus
-Hemagglutinin (HA) spikes: used for attachment to host cells -Neuraminidase (NA) spikes: part of the budding mechanism for viral exit -Treatment: Zanamivir and oseltamivir inhibit neuraminidase Prophylaxis: multivalent vaccine
Bacterial Meningitis
-Initially fever, headache, and stiff neck -Followed by nausea and vomiting -May progress to convulsions and coma -Diagnosis by gram stain and latex agglutination of CSF -Treatment: ceohalosporins, vancomycin
Chlamydia
-Most prevalent bacterial STI in the US (CDC -Cause by Chlamydia trachomatis -25% of men and 70% of women with no symptoms -Painful urination, discharge In men: leading to urethritis In women: cervix inflammation, salpingitis, PID, post-partum endometritis -Newborn conjunctivitis, pneumonia
Infections caused by S. pyogenes
-Necrotizing gasciitis (flesh-eating disease_ -Strep throat, laryngitis and pharyngitis -purerperal sepsis -scarlet fever -bacterial endocarditis -otitis media -Septic shock
Haemophilus influenzae Meningitis
-Occurs mostly in children (6 months to 4 years) -Gram-negative aerobic bacteria, normal throat microbiota -Capsule antigen type b -Respiratory route, also contaminated personal items -It has the distinction of being the first organism of any kind with completely decoded DNA (1995) -Prevent. by Hib vaccine
The challenge of Tuberculosis
-Once the leading cause of death in the US, still a serious concern -HIV-infected have several times higher incidence than general population -MDR-TB defined as TB resistant to rifampicin and isoniazid (first line ant0-Mycobacterium drugs) -XDR-TB multiple drug resistance. Rare in the US
Mycoplasmal Pneumonia
-One of the atypical or WALKING pneumonia -Mycoplasma pneumoniae -wall-less bacteria -Common in children and young adults
What are two of the conditions that define the systemic inflammatory response syndrome of sepsis?
-Sepsis -Septicemia
Pneumocococcal Pneumonia
-Streptococcus pneumoniae: the pneumococuss or diplococcus -Gram-positive encapsulated diplococci Symptoms: Infected alveoli of lung fill with fluid; interferes with oxygen uptake Diagnosis: optochin-inhibition test; serological typing of bacteria, PCR and direct DNA sequencing Treatment: Penicillin, fluoroquinolones Prevention: pneumococcal vaccine
Viral Lower Respiratory System Diseases: Pneumonia
-Viral pneumonia occurs as a primary infectious event -Or as a complication of influenza, measles, or chickenpox -Viral etiology is suspected if no other cause is determined.
Fungi, protozoans and animal parasites are easily distinguished from bacterial microbes by being
-in general large cells with many features -nucleated organisms -easily observed by light microscopy
Mary loved having her own garden and would often spend many hours tending to its care. She was meticulous in watering the plants, pulling the dreaded weeds, and harvesting the fruits and vegetables as they ripened. Her garden consisted of corn, tomatoes, green beans, okra, zucchini, squash, lima beans, watermelon, and cantaloupe. Often, the garden would produce much more than Mary and her daughter, Sue, could eat. Rather than waste the delicious food, the ladies would spend hours on the weekend canning the excess vegetables and fruit. It was something they had done for many years. On this particular occasion, Sue noticed that the pressure cooker, the instrument used to sterilize the canned food, did not seem to be acting quite right, but the cans were hot when they came out so she figured everything would be okay.Several months after their weekend of canning, the ladies invited the entire family over for Thanksgiving dinner. The meal consisted of turkey, ham, chicken, macaroni and cheese, rolls, spinach salad, tomatoes, corn, lima beans, green beans, and okra. All of the vegetables were the ones they had previously canned from their garden. For dessert, they had pecan pie and vanilla ice cream. The next day, while most of the family was out shopping, four of the family members were home with blurred vision, dry mouth, and muscle weakness. Mary called the family physician, Dr. Franklin, who told her to take the sick individuals to the emergency room, and he would meet them there. Upon arrival at the ER, Dr. Franklin asked what the family members had eaten for the meals before they developed the symptoms. The common foods that all of them ate were the chicken, the ham, the tomatoes, the green beans, and the spinach salad. The doctor determined that the family was suffering from botulism food poisoning. In the United States, foodborne botulism happens in 15% of cases each year, frequently from foods with a low acidity. He was suspicious of the green beans and tomatoes, even though tomatoes are highly acidic. Dr. Franklin also said that using proper methods of microbial control could have prevented their illness.
....
use of moist heat can control microbial growth in many circumstances, but heat-sensitive items and those susceptible to moisture cannot be sterilized in this manner. Which of the following correctly describes a method of physical control used to control microbial growth on or in such items?SELECT ALL THAT APPLY (ALL OF THEM)
1 Filtration is the passage of a liquid or a gas through a screenlike material with pores small enough to retain microorganisms. A vacuum is typically used to force the liquid through the mesh, and then the sterile liquid or gas is collected in a sterile container on the other side. 2 Nonionizing radiation, such as UV light, has a wavelength longer than that of ionizing radiation. The wavelengths of UV light are absorbed by cellular DNA in organisms directly exposed to the light. 3 Desiccation is a process that removes water from microorganisms, leaving them unable to grow or reproduce, but still viable. 4 Osmotic pressure is a process that uses high concentrations of salts and sugars to preserve food.
Botulism food poisoning is a preventable illness if special precautions are taken during food preparation. In this case, what could Sue have done to prevent the outbreak of botulism?Select all that apply.
1 Sue noticed that the pressure cooker was malfunctioning during the canning process. She should have fixed the instrument, borrowed a properly working one, or purchased a new pressure cooker. 2 Sue could have boiled the food for at least 10 minutes before serving it to her family members.
Which of the following is an example of microbial control? SELECT ALL THAT APPLY
1 Sue washes off the vegetables before serving them in a meal. 2 Sue uses bleach to clean the kitchen counters. 3 Mary places leftovers in the refrigerator after the meal.
Sodium nitrate and sodium nitrite are added to many meat products, such as ham, bacon, hot dogs, and sausage. These additives help to prevent the growth of Clostridium botulinum by inhibiting certain iron-containing enzymes of the organism. This is an example of chemical food preservation. Which of the following correctly describes a method of chemical control used to control microbial growth?Select all that apply
1 Surface-active agents, or surfactants, decrease surface tension among molecules of a liquid. 2 Phenolics exert antimicrobial activity by injuring lipid-containing plasma membranes, which causes the cellular components to leak out of the cell. 3 Alcohols exert their action by denaturing proteins and dissolving lipids.
What is the most likely sequence of events involved in the pathogenesis of meningococcal meningitis?
1) N. meningitidis enters and attaches to the nasopharyngeal epithelium 2) The organism passages through the mucosa and enters the blood 3) N. meningitidis crosses the blood-brain barrier 4) A massive influx of polymorphonuclear cells leads to increased pressure in the brain After entering the host, N. meningitidis will attach to epithelial cells (via fimbriae) lining the nasopharynx. After gaining access to the blood, the organism will be able to ultimately cross the blood-brain barrier. Throughout its passage through the body (and in the brain), N. meningitidis elicits a massive inflammatory response (due in large part to its lipooligosaccharide). In the brain, this influx of inflammatory cells leads to increased pressure. If left untreated (or treatment is delayed), this can lead to effects on hearing, vision, and/or motor skills.
Lactobacillus
1. Can derive lactic acid from glucose which creates an acidic environment (considered ACIDURIC***) 2. Produces LEXAN 3**** Lactobacillus are associated with advanced carious lesions DEEP in enamel AND are aciduric**** used as a probiotic
A microbe easily growing under refrigeration will have an optimal growth temperature closer to
25 degree celicus
The optimal temperature for growth of E. coli is closer to
25c
A Compound that merely inhibits the propagation of bacteria without killing them
A bacteriostatic
What animal does the infecting tick feed on just before it transmits Lyme disease to a human?
A deer
Now that you have considered the evidence at hand, you should start to build a hypothesis about what disease your patient has. In the beginning of your diagnostic process you should try and think broadly to help you consider any and all reasonable possibilities. You can then narrow down these possibilities by performing diagnostics that can support or refute your hypothesis.
A form of bacterial pneumonia Melioidosis Viral pneumonia, RSV, Coccidioidomycosis
What diagnostic test would be most useful at this stage of Dr. Peterson's diagnosis?
A lumbar puncture to obtain a sample of cerebrospinal fluid (CSF). In suspected cases of meningitis, a sample of CSF can be used for a variety of relatively quick diagnostic tests—the speed of results is essential in effective treatment. The lumbar puncture will not only be diagnostic of disease, but will allow for identification of the causative agent (Gram negative, Gram positive, or viral). This information is crucial for prompt treatment, which is essential for patient survival.
John's physician said that he might be suffering from Chikungunya fever, an emerging disease that once was limited to Asia, Africa, and Europe, but is now making appearances in the Caribbean and the United States. How did John most likely get infected?
A mosquito bite
fibrinogen
A plasma protein essential to blood clotting. The conversion of fibrinogen to its active form (fibrin) is among the final steps in clot formation, and is triggered by thrombin.
Which of the following best explains why the pressure cooker is so important in the canning process?
A pressure cooker utilizes steam to create a higher-pressure environment that allows the food to cook at higher temperatures than normal. The higher temperatures kill most contaminating microbes and endospores and therefore effectively sterilize the food.
coccus
A spherical bacterium.
Biofilms
A surface-coating colony of one or more species of prokaryotes that engage in metabolic cooperation.
neutrophils
A type of white blood cell(most abundant) that engulfs invading microbes and contributes to the nonspecific defenses of the body against disease. ENGULFS FOREIGN INVADING MICROBTES
Fungal Diseases of the Skin: Candidiasis (Candida albicans)
A yeast, normal microbiota -Candidiasis may result from suppression of competing bacteria by antibiotics -In skin and mucous membranes of mouth and genitourinary tracts -Thrush: infection of mucous membranes of mouth -More frequent in immunosuppressed patients -Topical treatment with miconazole or nystatin Systemic candidasis: -can affect immunosuppressed individuals -Can affect newborns Treatment: Fluconazole -Inhibitor of erogosterol biosynthesis
When microbial control methods are used, microbes are destroyed at a constant rate; there is no instantaneous death of all the microbes present. That microbial death rate is influenced by all of the following factors EXCEPT __________. A. toxins produced by the microbe B. the microbial characteristics C. the number of microbes D. the time of exposure
A. toxins produced by the microbe Although microbial toxins may influence the status of an infection, these factors do not influence the death rate of the organism.
The Big Picture Activity mentioned that because no vaccine is available, prevention is the next method for keeping the number of infections to a minimum. One of the methods recommended by the CDC is to prevent infected individuals from receiving mosquito bites during the first week of their infection. How does this help prevent further spread of infection?
Additional bites would increase the chances of an uninfected vector acquiring the virus. Uninfected vectors must acquire the virus from an infected human in order to transmit it to a new individual. The mosquito acquires the virus during a blood meal. Most infected individuals show the highest amounts of viral load, or highest numbers of virus particles in the blood during the first week of infection. By preventing the infected individual from being bitten, this decreases the chances of an uninfected mosquito acquiring the infection, thus limiting the spread of infection overall. Other methods of prevention mentioned in the Big Picture Activity include covering water sources that could be used as breeding grounds, trapping egg-laying females, and introducing sterile male mosquitoes to decrease the population.
Chickenpox (Varicella)
Adults version: shingles -Varicella-zoster virus ( human herpesvirus ) - HHV-3 -tRANSMITTED BY THE RESPIRATORY ROUTE - causes pus-filled vesickes -Pneumonia is a possible complication -Virus may remain latent in dorsal root ganglia -Prevention by live attenuated vaccine
STI home test kits are still relatively new on the market. Given their newness, it is necessary to weigh the benefits and the risks to doing the tests at home. Place each statement below in the appropriate bin.
Advantage -anyone can purchase and use -improved communication -increased treatment Disadvantage -kits can make mistakes -information leaks -increased costs
Your patient's samples show the presence of: gram-negative bacteria
Although gram-negative organisms classically have an outer membrane, they have a thinner peptidoglycan layer, which does not hold the blue dye used in the initial dying process. RED
monocytes
An agranular leukocyte that is able to migrate into tissues and transform into a macrophage.
Arboviral Encephalitis
Arboviruses -Arthropod-borne viruses that belong to several viral groups. Prevention: controlling insects (mosquitoes)
thermophiles
Archaea that thrive in very hot environments, such as volcanic springs.
Nicole is very upset after receiving news that her ex-boyfriend Paul had tested positive for syphilis and gonorrhea. She makes an appointment with her physician. Nicole receives her test results, which indicate that she is positive for syphilis, but not for gonorrhea. What treatment will her doctor most likely prescribe?
Antibiotics Nicole is very upset after receiving news that her ex-boyfriend Paul had tested positive for syphilis and gonorrhea. She makes an appointment with her physician. Nicole receives her test results, which indicate that she is positive for syphilis, but not for gonorrhea. What treatment will her doctor most likely prescribe?
Antigenic Variation in the Influenza Virus
Antigenic shift -Changes in HA and NA spikes -Probably due to genetic recombination between different strains infecting the same cell Antigenic drift -Point mutations in genes encoding HA or NA spikes -May involve only 1 amino acid -Allows virus to avoid mucosal IgA antibodies
In which of the following North American locations would you expect to find the highest incidence of infection with Borrelia burgdorferi?
Atlantic coast The northern part of the East Coast has the highest incidence of Lyme disease.
Which other recommendations will any pregnant mother be given in order to prevent exposure to pathogens that can be vertically transmitted? Select all statements that are correct.
Avoid cleaning cat litter boxes to prevent exposure to Toxoplasma gondii.
A patient has pneumonia. Gram-negative rods are cultured on nutrient agar from a sputum sample. The etiology is
Burkholderia pseudomallei.
Fungal Diseases of the Respiratory System: Pneumocystis Pneumonia (PCP)
Causative agent: Pneumocystis jurovecii -A yeast-like fungus -First condition recognized as opportunistic infection of AID Reservoir: unknown; possibly humans or soil Diagnosis: Microscopy Treatment: Trimethoprim (folic acid synthesis inhibitor)
Which is the technique that is essential to start the process of identification of bacteria?
Bacterial colony isolation and start pure cultures
Why is urethritis, an infection of the urethra, frequently preliminary to further infections of the urinary tract?
Because of the limited defenses of the urinary tract Urethritis can easily spread. Using urea as a nutritional source provides the bacteria with nearly an unlimited food source
Why are fecal coliforms used as a measure of water quality?
Because the main source of water contamination is animal and human waste
A patient has a paroxysmal cough and mucus accumulation. What is the etiology of the symptoms?
Bordetella
Blood agar with gentamicin
Burkholderia pseudomallei
Which of the following is least likely to be observed when diagnosing a case of bacterial meningitis?
CSF is completely clear and colorless. This would be an unlikely observation if bacterial meningitis is present. In a case of bacterial meningitis, the fluid is likely to be hazy or cloudy due to the white blood cells in the fluid.
Lyme disease
Causative agent: Borrelia burgdorferi Reservoir: Deer Vector: Ticks First symptom: Bull's eye rash Second phase: Irregular heartbeat, encephalitis Third phase: Arthritis - Long-term antibiotic treatment
Thrush and vaginitis are caused by
Candida albicans
A 35-year-old woman has a red, raised rash on the inside of her thighs. Gram-stained skin scrapings show large budding cells with pseudohyphae. The infection is caused by
Candida albicans.
Why might some cells uncouple the electron transport chain?
Cells can use the energy from the proton gradient for functions other than producing ATP, such as heat generation.
CDC
Center for Disease Control
The physician performs a pelvic exam, which reveals the presence of an abnormal thin, watery vaginal discharge and inflammation of the cervix. The physician then palpates the abdomen (examines by touch and pressure) and finds that the uterus, fallopian tubes, and ovaries are enlarged and tender. The physician takes a swab sample of the cervix and sends it to the laboratory to determine the causal organism. Light microscopy and simple staining of the sample in the lab reveal an organism with a very unique life cycle. The organism is classified as gram-negative, but it stains very poorly compared to other classic gram-negative STI pathogens. The stain shows both a nonreplicating, extracellular infectious elementary body and a replicating, noninfectious reticulate body inside mucosal cells from the cervical epithelium swab. Based on the symptoms and these new laboratory findings, which of the following would be the most likely diagnosis for the patient?
Chlamydia The physician makes a clinical diagnosis of chlamydia. Additionally, the exam shows that the patient has signs of progressive chlamydial pelvic inflammatory disease (PID).
The two most common STI organisms associated with PID in the United States are Chlamydia trachomatis and Neisseria gonorrhoeae. There are many similarities between these STIs. Which of the following statements comparing chlamydia and gonorrhea are true?
Chlamydia and gonorrhea can infect a patient and be transmitted without causing obvious symptoms. Patients may be coinfected with both gonorrhea and chlamydia. Chlamydia is found more often in women, whereas gonorrhea is found more often in men. STIs not only are hard to detect, but also are not mutually exclusive. When a patient has one STI, others may be "hiding in the shadows." STIs spread rapidly and can have consequences outside the urinary and reproductive tracts.
How does cyanide poisoning result in the decrease of ATP production?
Cyanide permanently reduces cytochrome a3, preventing other components to change into the oxidized state. This causes the proton gradient to break down, stopping ATP synthesis.
Disease in Focus: Bacterial Diseases of Urinary System A 20-year-old woman felt a stinging sensation when urinating and felt an urgent need to urinate, even if very little urine was excreted. Can you identify an infection that could cause these symptoms?
Cystitis
Urinary System Infections
Cystitis: An inflammation of the urinary bladder Urethritis: An inflammation of the urethra Pyeionephritis: An inflammation of one or both kidneys
UV radiation mainly causes
DNA mutations known as thymine dimers
Virus
During infection, the structure of influenza plays a vital role. Hemagglutinin (HA) mediates attachment to the host cells, after which the lipid envelope fuses with the host cell membrane. This allows the virus to be internalized, followed by release of the RNA genome from the capsid. Viral proteins will be produced, assembled, and released from the host cell. Release is mediated by neuraminidase (NA), and as the viral particles leave, they take part of the host membrane, thereby creating their envelope.
Which is a prime example of coliform bacteria?
E. coli
Encephalitis is an inflammation of what organ or organ structure
Encephalitis is inflammation in the patients brain
Gram-Negative Sepsis
Endotoxin shock: Endotoxins caused blood pressure to decrease - Produved among others by E. coli, and bacterial of the genera Salmonella, Neisseria, Klebsiella, Enterobacter. -Antibiotics can worsen condition by killing bacteria -increase endotoxin release
Which of the following is in general most resistant to the action of antibiotics, antiseptics and disinfectants?
Escherichia coli
Cystitis is most often caused by
Escherichia coli.
Most nosocomial infections of the urinary tract are caused by
Escherichia coli.
Infleunza (Flu)
Etiology: widespread RNA enveloped virus (Orthomyxovirus). Influenzavirus A, B, and C -Influenzavirus A mutates faster, is much more variable and is the cause of serious pandemics Symptoms: chills, fever, headache, and muscle aches MAIN CAUSE OF VIRAL PNEUMONIA -No intestinal symptoms -1% mortality, very young and very old
A microbe that enters the vagina would likely cause cystitis if left untreated.
False
A positive tuberculosis skin test indicates that the patient has active tuberculosis.
False
In a nitrate reduction test, multiple outcomes for a positive result are possible
False
Bacterial meningitis is much more common than viral meningitis and tends to cause a milder form of disease.
False VIRAL meningitis is much more common than BACTERIAL meningitis and tends to cause a milder form of disease.
Morphological characterization of bacteria includes all of the following EXCEPT
Fermentation tests
fimbriae
Fingerlike projection of the uterin (fallopian) tubes that drape over the ovary.
Structures that allow mobility common to many organisms are
Flagella, cilia and pseudopods
Staphyloccal skin infections
Folliculitis: Infections of the hair follicles Sty: Folliculitis of an eyelash Furuncle: Abscess; pus. surrounded by inflamed tissue Impetigo: crusting (nonbullous) sores, spread by autoinoculation
Yeasts, penicllium, mushrooms have in common
Fungi
Semisolid gelatin nutrient medium is routinely used to see if microbes contain
Gelatinase
Which of the following characteristics is the most useful for helping in morphological studies for bacterial identification?
Gram staining
Are the endotoxins that cause sepsis from gram-positive or gram-negative bacteria?
Gram-negative bacteria
Staphylococcus epidermidis
Gram-positive cocci, coagulase-negative, does not ferment mannitol, catalase-negative
Of the several hepatitis diseases, HAV, HBV, HCV, HDV, and HEV, which two now have effective vaccines to prevent them?
HCV. and HEV
viral
HSV-2 CMV
Chocolate agar with X and V factors
Haemophilus influenza
Based upon these results, which of the following could your patient have?
Haemophilus influenzae pneumonia Legionellosis Melioidosis
A one-year-old boy was listless, irritable, and sleepy. Encapsulated Gram-negative rods were cultured from his cerebrospinal fluid. His symptoms were caused by
Haemophilus influenzae.
Choose the false statement about Norovirus from those listed below.
Hand sanitizers are very effective for destroying Norovirus on the hands.
Arrange the following statements in the order that best describes the sequence of events involved in the replication of influenza
Hemagglutinin (HA) spikes attach to host cells. Influenza enters the host cell. Nucleic acid enters the host cytoplasm. Influenza proteins are synthesized. Influenza nucleic acid is packaged in capsid. Influenza particles bud from the cell, releasing the virus into the surrounding environment. After gaining entry to the host respiratory system, influenza adheres to host cells. The virus then enters the cells and begins the process of hijacking host machinery in order to produce new viral particles. After all the components are synthesized, they are assembled, and the virus leaves via budding. The newly released particles then infect neighboring cells, perpetuating the infection.
Herpes Simlex
Herpes simplex virus 1 (HSV-1) AND 2 (HSV-2) - Cold sore or fever blisters (vesicles on lips) - Herpes encephaliis (congential) - HSV-1 can remain latent in trigeminal nerve ganglia
Degradation by microbes of casein, starch or fats in the presence of water is the basis for
Hydrolysis tests
phagolysosome
Intracellular vesicle formed by fusion of a phagosome with a lysosome, in which the phagocytosed material is broken down by degradative lysosomal enzymes.
The at-home tests work similarly to pregnancy tests and are based on antigen-antibody reactions between the infectious agent and the patient's antibodies. Which class of antibody is most likely to give a result in the assay?
IgG The at-home STI tests are similar to ELISA tests and the assay for IgG antibodies because they last the longest in the bloodstream. If the individual is positive for the infection, they will have antibodies that will bind in the lab tests to the STI antigen.
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 would conjugation to a protein carrier improve the efficacy (i.e. improve the immune response generated by the vaccine) of a polysaccharide vaccine?
In contrast to polysaccharide vaccines, protein-conjugated vaccines elicit a strong T-cell dependent response. The addition of a protein conjugate stimulates T cells to respond. This will generate a strong immune response characterized by generation of IgG-producing plasma cells and memory T cells.
As you read off the above questions to your patient, you start to get a feeling for the ubiquity of Legionella pneumophila in water sources. If Legionella is so common, then why doesn't everyone get sick? Generally, the risk of contracting legionellosis is low for an immunocompetent person; however there are some factors that seem to increase the likelihood of contracting the disease. Which of the following factors specific to your patient do you think played a role in whether or not he got sick once exposed to the bacterium?
His age His cigarette and alcohol consumption His travel history Men over the age of 50 are the most likely to contract legionellosis, especially if they are heavy smokers or drinkers.
What type of specimen was used to observe trypanosomes and malaria parasites?
Infected blood samples
The most common antiseptic is
Iodine
Why is postexposure vaccination for rabies a practical option?
It is practical because the vaccination is only needed if the animal that bit a person is positive for rabies.
Tuberculosis
It is responsible for nearly 2 million deaths per year. At least 1/3 of those who are TB-positive are also HIV-positive. Treatment requires at least six months of antibiotic therapy. Nearly 1/3 of the world's population is infected with tuberculosis.
Which of the following statements about sepsis is FALSE?
It most always is self-limiting
Buffered charcoal-yeast extract agar
Legionella pneumophila
Legionellosis (Legionaires' Disease)
Legionella pneumophila -Gram-negative rod -Found in water -Transmitted by inhaling aerosols; not transmitted from human-to-human.
Diseases in focus: Viral Hepatitis After eating at one restaurant, 355 people were diagnosed with the same hepatitis virus Can you identify infections that cold cause these symptoms?
Leprosy is characterized by loss of sensation in areas of the skin, and tetanus causes uncontrolled muscle contractions. Early symptoms of poliomyelitis include sore throat and nausea. Rabies, sleeping sickness, and CJD do not cause paralysis. (It is important to consider the most likely diseases first, and there is no indication that the patients traveled to trypanosome-endemic areas.) The progressive (descending) paralysis is characteristic of botulism. The photo shows endospore-forming rods cultured from the canned chili. The presence of botulinal toxin in the chili or in the patient's feces is confirmed by mouse bioassay. This can take several days, so the initial clinical findings are usually diagnostic. treated w/ antitoxin
Microscopic examination of cerebrospinal fluid reveals gram-positive rods. What is the organism?
Listeria
All of the following organisms are transmitted via the respiratory route EXCEPT
Listeria monocytogenes.
Pneumonia
Lung inflammation with many etiologies -Bacterial orgin: more than 2/3 of all -Streptococcus pneumoniae (50%) - Haemophilus influenzae (20%) -Atypical pneumonias Usually milder than those above and of viral orgin -Mycoplasma pneumoniae (3%) -CHlamydophila pneumoniae (13%) -Legionella pneumophila -Viral orin: 1/3 of all Main viral sources: rhinoviruses, coronaviruses, influenza virus, RSV Combine viral and bacterial presence in up to 45% of infant and 15% of adult pneumonias
Which organelle would play the most direct role in eliminating bacteria engulfed by a phagocytic white blood cell?
Lysosome Lysosomes contain a variety of different hydrolytic enzymes that would ultimately digest the engulfed bacteria.
Which of the following organelles breaks down worn-out organelles?
Lysosomes contain digestive enzymes and break down worn-out organelles.
All of the following microorganisms can directly cause meningitis EXCEPT
M
In microbiology class, a pregnant student learned about the TORCH test. This panel of tests was originally developed to screen mothers for antibodies to microbes that can harm their fetuses. Which of the following microbes and diseases are included in the TORCH test?
Measles Rubella Herpes Chickenpox
Koplik spots are a diagnostic indicator of
Measles (Rubeola)
Measles (Rubeola)
Measles virus -Transmitted by respiratory route, extremely contagious -Koplik's spots and macular rash -Prevented by vaccination -Alternative name in English-speaking countries
The TORCH Panel of Tests
Medical acronym for perinatal infections conditions (passed across the placenta to the fetus) that can lead to severe birth defects or fetal loss -Toxoplasmosis -Syphilis -Hepatitis B -enterovirus -Epstein-Barr virus -varicella-zoster virus -HIV -Rubella -Cytomegalovirus -Herpes simplex virus
The Nervous system
Meninges: protect brain and spina cord -Dura mater: outermost layer -Arachnoid mater: middle layer -Subarchnoid space contains cerebrospinal fluid (CSF) -Pia mater: Innermost layer Blood-brain barrier: prevents passage of antimicrobial principles
Neisseria Meningitis
Meningococcal meningitis -Caused by Neisseria meningitidis (the meningococcuss) -Gram-negative, aerobic encapsulated cocci -10% of people are healthy nasopharngeal carries -Respiratory route, also contaminated personal items -Begins as throat infection, rash -Multiple serotypes -Vaccination includes all U.S. serotypes; recommended for college students
A more detailed characterization of fermentation products is carried out by the
Methyl Red and Voges-Proskauer (MR-VP) tests
Where in a cell is ATP made?
Mitochondria
What group of bacterial pathogens causes what is informally called "walking pneumonia"
Mycoplasmal pneumonia
What is the likely cause for the drop in glucose levels?
N. meningitidis uses the glucose as a source of energy to fuel its growth. The nutrient-rich environment provided by CSF provides ample glucose to support N. meningitidis growth. This glucose allows N. meningitidis to grow very rapidly; this in turn stimulates a greater inflammatory response as cells move into the CSF to fight the infection. Interestingly, since viruses do not utilize glucose to support their growth, the decreased CSF glucose is not observed in patients with viral meningitis.
Nucleic Acid Amplification Testing (NAAT)
NAAT or nucleic acid amplification testing screens for chlamydia, gonorrhea, and trichomoniasis. These tests amplify nucleic acids from the organism causing the sexually transmitted infection. The data is then compared to known results to diagnose possible infections. Individuals can obtain their results by phone using a password. Anyone with a positive result is encouraged to visit a physician's office.
Which one of the following statements regarding tuberculosis is FALSE?
Nearly 1/3 of the world's population shows symptoms of tuberculosis.
Based on Claire's medical history and the Gram stain results, which is the most likely causative organism?
Neisseria meningitidis N. meningitidis is a Gram negative coccus (usually diplococcus). The Gram negative diplococci and large number of polymorphonuclear leukocytes are both clear in the micrograph of the CSF sample.
Which of the following is used to study a substance with nitrogen as an alternative to obtain energy by microbes?
Nitrate test
Given the above results, is it safe to say your patient has a MRSA infection?
No MRSA stands for methicillin-resistant Staphylococcus aureus. Your patient is infected with a strain of S. aureus that is resistant to penicillin, but still sensitive to methicillin
Norovirus
Norovirus has a very small infective dose Norovirus is the most common type of nonbacterial gastroenteritis. A 1:10 bleach solution (1,000 ppm) is useful for environmental disinfection or Norovirus Symptoms: Vomiting Diarrhae 2-3 Us main gastroenteritis agent Transmission: Fecal-oral route Direct contact Droplets Predisposing factors: Crowding such as in college campuses, community living, cruise ships. Incubation: 14-48 hours Diagnosis: PCR Treatment: Oral rehydration
Nicole received her diagnosis at her physician's office. Which of the following procedures was most likely used by the physician to confirm her infection?
Nucleic Acid Amplification Testing (NAAT)
Where is the genetic information of the cell stored?
Nucleus DNA is the genetic information of the cell, and it is stored in the nucleus.
You would like to determine which species of Staphylococcus your patient is infected with. Which test will allow you to eliminate some possibilities?
One of the most important phenotypic features that can be used to differentiate among Staph species is their ability to produce coagulase , an enzyme that causes blood clot formation
Escherichia coli Gastroenteritis
Pathogenic E.coli -Attach to intestinal cells with fimbriae -Produce toxins -May aggregate Pathogen: Enterotoxigenic Enteroinvasive Enteraggregative Shiga toxin-producing E. coli Symptoms: Watery diarrhea Shigella-like dysentery; hemorrhagic colitis and hemolytic uremic sydrome Intoxication/Infection: Infection Endotoxin Infection Shiga exotoxin Diagnosis Isolation of bacteria Treatment: Oral rehydration Quinolones; cephalosporins
Another name for pertussis is whooping cough. This symptom is caused by the pathogens' attack on which cells?
Pertussos causative agent: Bordetella pertussis symptoms:cough prevention: DTaP-the symptom of coughing is caused by the pathogens' attack on ciliated cells Tuberculosis acid fast aerobic causative agent: Mycobacterium tuberculosis symptoms: loss of weight, appetite, energy, night sweats prevention: vaccine: BCG--live but don't use in united states
What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?
Plasma membrane surrounds the cell and regulates the movement of materials into and out of the cell. Return to Assignment
The logical sequence of steps to determine the efficacy of antibiotics is
Plating of bacteria; laying of disks embedded with antibiotics; plate incubation; measurement of inhibition zones
Streotococcus pneumoniae Meningitis
Pneumococcal meningitis -Caused by S. pneumoniae -Gram-positve encapsulated bacteria, the diplococcus or pneumococcus -70% of people are healthy nasopharyngeal carriers -Same transmission by respiratory droplets as the 2 before -Most common in children (1 month to 4 years) -Mortality: 30% of children, 80% in elderly -Prevented by vaccination
pelvic inflammatory disease (PID)
Polymicrobic, usually -N. gonorrhoeae -C. trachomatis -Salpingitis (infection of uterine tubes) Symptoms: Chronic abdominal pain -PID contributes to reduced fertility/sterility Treatment: doxycycline and cefoxitin (a cephyalosporin_
What is NOT true about gram-negative sepsis?
Potent exotoxins cause shock.
Sexually Transmitted Infections (STIs)
Prevented by condoms, abstinence; reduced by testing, male circumcision. Bacterial infections are treated with antibiotics Example: CHLAMYDIA MOST PREVENT IN US
In a sugar fermentation tube, the presence of an inverted glass bell allows to detect
Production of gas
One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by
Ribosomes Ribosomes dock on the rough ER, and proteins are completed inside the rough ER.
Sepsis and Septic Shock
Septicemia: persistent pathogen pr their toxins in blood Sepsis: Systemic inflammatory response. Drop in blood pressure Septic shock: Sepsis and uncontrollable decreased blood pressure
Bacillus
Rod shaped bacterium
Viral Gastroenteritis
Rotavirus ad Norovirus
Which bacterial species features the virulence factor M protein?
S.pyogenes
exfoliative toxin
Scalded skin syndrome - Impetigo of the new born -Mechanism of action not clear
Before you can treat you patient, there is a very important factor you must consider.
Selecting the best drug to treat Staphylococcus aureus infections can be difficult because some strains of the bacteria have developed drug resistance .
Disease in Focus infections from Human Reservoirs A 27-year-old woman had a fever and cough for 5 days. Despite aggressive treatment with fluids and massive doses of antibiotics, she died 5 hours later. Catalase-negative, gram-positive cocci were islate from her blood, What infections could cause these symptoms?
Septic shock- drop in blood pressure and presence of bacteria in the blood. Streptococci is most likely one.
Whooping cough
Stage 1: Catarrhal stage, like common cold Stage 2: Paroxysmal stage-violent coughing sieges Stage 3: Convalescence stage
Diseases in Focus: Bacterial Disease of the lower digestive system An 8 year old body had diarrhea, chills, fever (39.3 celcius), abdominal cramps, and vomiting for 3 days. The next month, his 12-year-old brother experienced the same symptoms. Two weeks before the first patient became ill, the family had purchased a small (10cm) red-eared slider turtle at a flea market. Identify infection that could cause these symptoms
Staphylococcal food poisoning is not accompanied by a fever and the two boys did not have their symptoms at the same time; these facts eliminate an intoxication. The absence of serious diarrhea eliminates cholera and shigellosis; the absence of a high fever eliminates typhoid fever. Association with a reptile, especially a small turtle that is easily handled and is moist with water containing its feces, indicates salmonellosis.
Microbial diseases of the skin
Staphylococcal skin Infections: Staphylococcus epidermidis Staphylococcus aureus Streptoccal skin infections: Gram-positive chained cocci - Streptococcus pyogenes -Group A beta-hemolytic streptcocci Hemolysins, Hyaluronidase, Streptolysin, M proteins
These results support the idea that your patient's infection was caused by ______.
Staphylococcus aureus
Furuncles, toxic shock syndrome, and scalded skin syndrome all are caused by
Staphylococcus aureus.
The patient has vesicles and scabs over her forehead. Microscopic examination of skin scrapings shows gram-positive cocci in clusters. The etiology is
Staphylococcus aureus.
Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa
Staphylococcus aureus: -Gram-positive cocci, coagulase-positive, ferment mannitol, catalase-positive -Much more frequently pathogenic than S.epidermidis -About 20% of people are healthy masal carriers
Iodine reagent is commonly used to detect
Starch
alpha-hemolytic streptococci
Strep. pneumoniae Viridians Strep Group D Strep Enterococcus
SIM medium stands for
Sulfide, indole, motility
Enterotoxins
Superantigen -Responsible for food poisoning by S. aureus
Sepsis
Symptoms include fever and decreased blood pressure. It may be aggravated by antibiotics. Lymphangitis may occur. It usually is caused by gram-positive bacteria.
gonorrhea
Symptoms: In women: -Few symptoms but possible complications, such as PID -burning urination In men: Painful urination and discharge of pus Diagnosis: Gram stain, ELISA, PCR Treatment: Fluoroquinolones
Mumps virus
Symptoms: Swollen parotid glands, orchitis (testicle inf.) Transmission: Droplets, direct contact Predisposing factors: Childhood disease, seasonal Incubation: 16-18 days Diagnosis: Symptoms Treatments: Vaccine (MMR)
Rotavirus
Symptoms: Vomiting Diarrhea 1 week Transmission: Fecal-oral route Predisposing factors: Crowding such as in college campuses, community living, cruise ships, hotels, camps, ect. Incubation: 1-3 days Diagnosis: EIA Treatment: Oral rehydration; vaccine
Legionellosis
Symptoms: potentially fatal pneumonia that tends to affect older men who drink or smoke heavily, have chronic diseases or suffer from immune deficit Diagnosis: culture on selective media, DNA probe, PCR amplification and DNA sequencing Treatment: erythromycin
TORCH
The TORCH is a panel of tests that was originally developed to screen pregnant women for the presence of antibodies to various microbes that can be vertically transmitted and harm unborn children. TORCH is an acronym for "T"—Toxoplasmosis, "O"—Other (e.g., chickenpox, HIV, measles), "R"—Rubella, "C"—Cytomegalovirus, "H"—Herpes simplex virus.
Why does lack of oxygen result in the halt of ATP synthesis?
The chain shuts down and can no longer pump hydrogen ions across the membrane, and the proton gradient cannot be maintained.
Claire's symptoms are characteristic of many different infections. Why does Dr. Peterson suspect that Claire may have meningitis?
The closed, mixed environment of the college dorm allows for infection of susceptible students. - There have been documented cases of meningitis in Claire's dorm. Living in closed quarters such as a dormitory exposes college students to novel bacterial serotypes unfamiliar to their immune system. Without prior exposure or vaccination, students are susceptible to infection by these serotypes. The closed environment of the dorm provides an ideal environment for exposure and transmission—as evidenced not only by Claire's case but by the earlier documented cases.
When there are serious local outbreaks of arboviral encephalitis, what is the usual response to minimize its transmission?
The control of insects; for example mosiquitoes. In order to rid the local outbreaks from arboviral encephalitis the whole insect population must be killed.
Of the two diseases caused by the pathogen you isolated, ___________fits your patient's symptoms the best
legionellosis
What diseases could result from the organism you cultured?
legionellosis Pontiac fever
Why is paralytic polio more likely to occur than a mild or asymptomatic infection in areas with high standards of sanitation?
The high levels of sanitation prevent exposure during infancy when maternal antibodies are present so, during adolescence and adulthood, if the subject is exposed the virus is more serious.
Why is bacterial meningitis considered more life threatening than viral meningitis?
The immune response generated against bacteria leads to a massive influx of immune cells in the meninges; this response is much less extreme in viral meningitis. While both pathogens induce inflammation in the meninges, the overall number of cells entering the CSF during viral meningitis is much lower. In addition, the CSF in bacterial meningitis will contain primarily neutrophils while CSF in viral meningitis will contain primarily lymphocytes.
An individual presents with a pinkish-red rash and a red sore throat. Gram-positive cocci are cultured from a throat swab and demonstrate beta hemolysis on the blood agar plate. The cocci are growing in chains. Which of the following is the most likely conclusion?
The patient has scarlet fever.
Which is true of the Mumps virus?
The portal of entry is the respiratory route.
Zika Virus
The signs and symptoms (fever, headache, muscle and joint pain, malaise, skin rash, and conjunctivitis) that Jane is experiencing could be indicative of an infection with Zika virus (ZVD—Zika virus disease). This virus is transmitted by Aedes mosquitoes that may be found in the Caribbean, South America, and also the southern United States. ZVD will be confirmed by RT-PCR.
gram-negative sepsis
The site of infection itself may not be the bloodstream. LPS is released upon death of the cells. The rapid progression is almost impossible to treat effectively. The progression to lethal stages is rapid.
Your patient's samples show the presence of: gram-positive bacteria
The staining method uses crystal violet dye, which is retained by the thick peptidoglycan cell wall found in gram-positive organisms. This reaction gives gram-positive organisms a blue color when viewed under a microscope PURPLE
lymphocytes
The two types of white blood cells that are part of the body's immune system: B lymphocytes form in the bone marrow and release antibodies that fight bacterial infections; T lymphocytes form in the thymus and other lymphatic tissue and attack cancer cells, viruses, and foreign substances.
Which statement regarding normal microbiota of the human respiratory system is FALSE?
The upper respiratory tract is mostly sterile.
There are many types of HPV, and the available vaccines don't (can't) cover all of them. However, the vaccine is still recommended for helping to control the disease caused by the virus. Why?
The vaccine covers strains frequently associated with development of cancerous states.
Which of the following statements concerning viral sexually transmitted infections (STIs) is true?
The viral infections that cause genital warts and herpes can be treated but not cured.
What are some of the current challenges to production of the influenza vaccine?
The virus undergoes antigenic changes on a regular basis. In order to yield a vaccine, the virus must be produced in eggs A vaccine for influenza has been available since about 1945. The current vaccine generates protection against the three strains most likely to cause infection during the flu season. The vaccine is currently available in two forms: a nasal spray (made from live, attenuated virus) and an injection (made from inactivated virus). Although both offer protection, the effect is relatively short-lived and is specific only for the three strains contained in the vaccine.
Treatment of Tuberculosis
Therapy: Prolonged treatment with multiple antibiotics Vaccines: BCG, live avirulent M. bovis; not widely used in the U.S.
What is a likely result of the elevated WBC level in Claire's CSF?
There will be an extreme inflammatory response which will eventually lead to shock and ultimately to Claire's death. The massive influx of WBCs (primarily neutrophils) will be accompanied by a massive release of pro-inflammatory cytokines, which ultimately leads to shock.
What do the following four diseases/infections have in common: plague, Lyme disease, toxoplasmosis, anthrax?
Theses infections are all zoonotic.
In which of the following respects is measles similar to German measles (rubella)?
They can be controlled by vaccination
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
Why did you cover one-half of each plate to be exposed to UV radiation with a card?
To protect half of the surface of the plate from irradiation and leave it as a control
Superantigen: TSS1
Toxic shock syndrome toxin 1 (TSS1) - a superantigen - causes toxic shock syndrome
neither bacterial or viral
Toxoplasma gondii
Cats have been identified as an essential part of the life cycle for the protozoan that causes which disease?
Toxoplasmosis is caused by Toxoplasma gondii.
Chlamydia PID is just part of the overall spectrum of disease caused by Chlamydia organisms. Even though we now understand more about STIs and their complications, we are still exploring how the organisms "branch out" beyond just a single infection. Which of the following diseases have Chlamydia infection as an etiology?
Trachoma, inclusion conjunctivitis, pneumonia, cervical cancer, infertility, lymphogranuloma venereum (LGV) Mixed STI infections (which may involve both different species and different strains of the same species) are able to manifest in an infected patient with more than just the classic "clap" symptoms. The caregiver should always be aware that more may be going on in the patient than meets the eye and act appropriately to instruct the patient on routes of spread the person might not anticipate.
Natural selection is a gradual, nonrandom process by which biological traits become more or less frequent within a population. Which of the following are necessary conditions for natural selection to occur within a population of Staphylococcus aureus?
Traits that permit an individual to survive at least until reproduction will increase in frequency over time. Traits are hereditary. Some individuals in the population reproduce more than others.Individuals in the population vary from one another. Because individuals in a population differ from one another and can pass these differences on, the genes of individuals that survive to reproduce will increase in the population over time. The length of time it takes for these genes to increase within a population of bacteria is relatively short. There are several reasons for this: bacteria have relatively large population sizes and short generation times; bacteria also can pass their genes on to others by either vertical (from parent to offspring) OR horizontal transfer (one bacterium can pass a plasmid to another). All of these factors influence the rate at which genetic variations can arise and be sustained in a population.
Tuberculosis Diagnosis
Tuberculin skin test (Mantoux reaction) screening -Positive reaction means current or previous infection -Followed by X-ray or CT exam, acid-fast staining of sputum, culturing of bacteria
Toxoplasmosis. (Toxoplasma gondii)
Transmission: -Ingesting undercooked meat -Contact with cat feces -Transplacental/brith canal -Congential infection -Stillbirth -Neurological damage
Hepatitis E
Transmission: Fecal-oral Pathogen: Calicviridae Chronic liver disease no Vaccine? No vaccine
Hepatitis A
Transmission: Fecal-oral Pathogen: Picornaviridae Chronic liver disease: No Vaccine? Inactivated virus
Hepatitis C
Transmission: Parenteral Pathogen: Flaviviridae Chronic liver disease Yes Vaccine? No vaccine (antigenic variants)
Hepatitis D
Transmission: Parenteral, HBV coinfection Pathogen: Deltaviridae Chronic liver disease yes Vaccine? HBV vaccine
Hepatitis B
Transmission: Parenteral, STI Pathogen: Hepadnaviridae Chronic liver disease: yes Vaccine? Recombinant
Which one of the following statements about mycoplasmal pneumonia is TRUE?
Treatment is Tetracyclines
bacterial
Treponema pallidum Elizabethkingia Listeria monocytogenes
Nicole knew that these were both sexually transmitted infections caused by bacteria. Which of the following is correct regarding the causative agents for these diseases?
Treponema pallidum causes syphilis, while Neisseria gonorrhoeae causes gonorrhea
Catalase test is useful for identification purposes to distinguish between closely-similar gram-positive bacteria
True
It is common for a normal, healthy individual to carry potentially pathogenic organisms in their upper respiratory tract.
True
The oxidase test detects an enzyme only present in aerobic microbes
True
Salmonelosis and typhoid fever are cause by closely related organisms. Why was typhoid fever almost entirely eliminated in developed countries by modern sewage treatment whereas salmonellosis has not been?
Typhoid gever has been almost eliminated in developed countries by modern sewage treatment whereas salmonellosis Typhoid fever spreads by feces of humans. Proper sewage disposal, water treatement, and food sanitation makes in uncommon.
Which of the following situations does not result in a breakdown of the proton gradient?
Uncoupling proteins
In fermentation tests, you used medium with the following substrates EXCEPT
Urea
You carefully think over these results. You ultimately decide to drain the pus from the carbuncle and dress the wound. You instruct the boy and his family about proper wound care and decontamination to prevent the spread and recurrence of the infection. Why did you not prescribe antibiotics in this case?
Using antibiotics can accelerate drug resistance in Staph. Antibiotics can weaken the immune system. Antibiotics have side effects. Antibiotics will kill off beneficial bacteria. With careful supervision, your patient's wound heals well. Many health professionals agree that if a Staph infection can be treated without the use of antibiotics, it should be! Unnecessary antibiotic use for staphylococcal infections can double the probability of developing future MRSA infection. You made responsible choices with the treatment you administered, and if these sort of smart choices continue, you may be able to fight drug-resistant bacteria more efficiently.
Cystitis
Usual causative agents: E. coli Symptoms: Dysuria(difficult or painful urination) Diagnosis: > 100 CFU (colony forming units)? ml potential pathogen and positive LE test Treatment: trimethoprim - sulfamethexazole Inhibitors of the folate pathway
vertical trasmission
Vertical transmission occurs when microbes are passed from the mother to the fetus via the placenta or during delivery. These microbes may not cause harm to the mother while severely affecting the baby.
Which of the following statements about meningitis is TRUE?
Viral meningitis, while less severe than bacterial meningitis, is more common in occurrence.
Which of the following statements regarding antigenic shift are true?
Viral strains resulting from antigenic shift contain RNA segments from different species. Antigenic shift results in a major change in the genetic composition of the virus. Little immunity to virus strains resulting from antigenic shift exists in the population. Genetic analysis of the 1918 flu revealed that it contained genetic material that was both avian and mammalian in origin. This reassortment led to a deadly combination—a virus that was both highly virulent and transmissible. These factors, coupled with the lack of immunity in any population, led to the pandemic that impacted the entire world.
A pregnant woman found a large variety of microbes that can be vertically transmitted. She is making a list for her doctor to assess her risk of becoming infected with any of them. Match the infectious agents with their respective classification.
While a select group of pathogens may not harm the mother and cause only minor signs and symptoms, they may have detrimental adverse effects on an unborn child. Viral pathogens that can be vertically transmitted include herpes simplex virus 1 and 2, Zika, and Cytomegalovirus. Bacterial pathogens that can be vertically transmitted include organisms such as Treponema pallidum, Listeria monocytogenes, group B Streptococcus, and a newly discovered Elizabethkingia. The protozoan Toxoplasma gondii may also be transmitted vertically.
If a person in the United States is exposed to rabies, which animal is the most likely culprit?
Wild bats
Why is E. coli the most common cause of cystitis, especially in females?
Women are particularly at risk for UTIs because their urethra sits close to the anus, where E. coli is present. It's also shorter than a man's, giving the bacteria easier access to the bladder, where the majority of UTIs occur, and the rest of the urinary tract.
You have a culture of bacteria that you suspect is either Staphylococcus aureus or Streptococcus pyogenes. Is there any morphological difference between the two?
Yes. Microscopically, S. aureus typically forms gram- positive cocci in clusters, whereas S. pyogenes forms gram-positive cocci in chains.
The primary victims of the influenza pandemic of 1918-1919 were
Young Adults
After returning from a family trip to Brazil, suffering from a fever and experiencing some minor joint and muscle pain and conjunctivitis, a pregnant woman has an appointment with her doctor. What will the doctor likely be testing her for after learning about her trip?
Zika virus disease
Superantigen
a class of antigens that cause non-specific activation of T-cells resulting in polyclonal T cell activation and massive cytokine release
Assume that your lab partner swabs the side of his face and uses the swab to inoculate a nutrient agar plate. The next day, he performs a Gram stain on the colonies. They are gram-positive cocci. You advise him that he should next look for
a coagulase reaction.
Our patient needs antibiotics to overcome this infection and prevent any further complications. Which of the following would be the best choice?
a combination therapy of cephalosporin-class AND macrolide-class. After 3 days of hospitalization for antibiotic therapy, monitoring, and laboratory testing to assess the function of her reproductive systems, the patient is released to go home. She is discharged with a short course of antibiotics, educational materials about STIs (with multiple copies so that she can notify and inform her partners), and instructions to follow up with her gynecologist for yearly checkups.
In the complete qualitative analysis of water, you combined
a fermentation medium and plate colony counts
Toxoplasma gondii
a protozoan pathogen that can be transmitted via ingestion of infected, inadequately cooked meat, and ingestion of oocysts from cat feces possibly acquired while cleaning cat litter boxes. It is advised that pregnant women avoid cleaning cat litter boxes or in case no help is available, gloves should be worn to prevent accidental ingestion of the infectious cells.
Legionelllosis is a nationally reportable disease, and you must notify the authorities of your finding. Before you call in your diagnosis however, you want to try and identify how your patient first contracted it. You decide to question your patient about his possible exposure history in the ten days before his illness. You ask him if he has been in, around, or used:
a shower (away from home, )long-term care, senior, or assisted living facility (e.g. nursing home, rehab facility), a steam room or sauna, grocery stores with misters for fruit and vegetables, a mall or other large enclosed shopping venue, any form of respiratory therapy equipment (e.g. sleep apnea, asthma devices), a hotel, a hospital (besides his current stay), recreational misters, a doctor's or dentist's office, a decorative fountain, a pool, hot tub, jacuzzi or whirlpool spa, construction or projects affecting, plumbing and/or water lines, a humidifier
The bacteria appear to be in clusters, as opposed to chains. This suggests that your patient has ______.
a staphylococcal infection
Which statement about antibiotic use is CORRECT? a.If tetracycline is effective against gram-positive, gram-negative, Chlamydia and Mycoplasma microbes, tetracycline must be a broad-spectrum antibiotic b.If an antibiotic is effective against gram-negative bacteria in a disk-diffusion test, it means that it must be effective against gram-positive microbes as well c.If penicillin is effective against gram-positive bacteria in a disk-diffusion test, it means that it must be effective against gram-negative microbes as well d.If tetracycline is effective against gram-positive, gram-negative, Chlamydia and Mycoplasma microbes, tetracycline must be a narrow-spectrum antibiotic
a.If tetracycline is effective against gram-positive, gram-negative, Chlamydia and Mycoplasma microbes, tetracycline must be a broad-spectrum antibiotic
Mycobacterium
acid-fast rod
AIDS
acquired immune deficiency syndrome A serious (often fatal) disease of the immune system transmitted through blood products especially by sexual contact or contaminated needles.
John mentioned that while in the Caribbean, he had been very careful to wear bug spray when outside and to use a mosquito net around the bed at night. Why were these protective measures not enough to keep him from being infected?
aedes mosquitoes prefer to live inside buildings, are more resistant to bug spray, and feed during the day. The mosquitoes' preferences to live inside and to feed during the day contributed to John's chances of being infected. The bug spray was less effective against the indoor mosquitoes than those that were outside. The net around the bed would have protected the couple at night, but the mosquitoes carrying Chikungunya prefer to feed during the day.
Legionella is transmitted by
airborne transmission.
A hydrogen bond
an attraction between hydrogen and more electronegative atoms that are themselves involved in polar covalent bonds.
Predict which of the following would be outcomes of treatment with Tamiflu.
an increase in the ability of the immune system to combat the infection overall decrease in the replication rate of influenza a decrease in the release of viral particles from the cell If taken within 30 hours of the appearance of symptoms, Tamiflu is quite effective at inhibiting viral replication. Because NA has been inhibited, the viral particles are unable to bud from the infected cells. As a result, the infection isn't perpetuated. This slowing in the replication cycle gives the body enough time to mount an effective immune response and eventually eliminate the infection.
Antibiotics that prevent the formation of bacterial cell walls
are mostly synthetic chemicals, man-made in an organic chemistry lab
A motile bacterium in SIM medium appears
as cloudiness occupying most of the growth space in the tube
Which organism does not belong with the others? a.Yeasts b.Penicillium c.Plasmodium d.Mushrooms
b. Plasmodium
you exposed bacteria plates in the UV boxes without their lids
because plastic is a barrier to UV radiation
The most effective disinfectant is
bleach
Polar covalent bonds
can result in partial charges and the attraction of molecules with opposite partial charges.
Gonorrhea
caused by Neisseria gonorrhoeae (the gonococcus) -Gram-negative, immnity-evading facultative anaerobe diplococcus -Encapsulated -Antigenic variation -Attaches to oral or urogenital mucosa by fimbriae -Opa proteins prevent CD4+ T-cell proliferation -Multiple drug resistance -Anal gonorrhea, pharyngeal gonorrhea If left untreated, may result in -Endocarditis -Meningitis -Arthritis -Ophthalmia neonatorum (congenital)
Syphilis
caused by Treponema pallidum STI. Invades mucosa or through skin breaks. Also congenital. Treatment: slow-release penicillin
Morphological characterization of bacteria includes all of the following
cell shape and arrangement Gram staining presence of occasional structures like capsule and endospores
CNS
central nervous system; brain and spinal cord
CSF
cerebral spinal fluid
Pyschrophiles
cold-loving microbes
marcophages
contain numerous lysosomes for intracellular degradation of phagocytized macromol a large phagocytic cell found in stationary form in the tissues or as a mobile white blood cell, especially at sites of infection.
The most common mode of HAV transmission is
contamination of food during preparation
Interferons (IFNs)
control of viral infections, regulation of inflammatory response INTERFER
The structural framework in a cell is the
cytoskeleton The cytoskeleton is the structural framework in a cell ("cyto" refers to cell and "skeleton" refers to a structural framework).
zoonotic
occurs primarily in wild and domestic animals and can be transmitted to humans.
To evaluate the effect of temperature on microbial growth
different bacteria were grown together in multiple replicate plates each incubated at a different temperature the same bacteria was grown in multiple plates at different temperatures
hemolytic
destruction of red blood cells
All of the following are true of the common cold EXCEPT
early treatment will drastically reduce the disease symptoms.
The most effective control of mosquito-borne disease is
elimination of the mosquito population
A possible complication of chickenpox is
encephalitis.
Arboviruses cause ________ and are transmitted by ________.
encephalitis; mosquitoes
How will you treat this disease?
erythromycin
Which of the following matches the organisms described with the correct domain?
eukarya--single-celled and multicellular organisms, with a defined nucleus and a variety of nutritional sources Eukarya is the domain that includes only organisms with cells that have a true nucleus. These organisms belong to the nutritionally diverse Kingdoms Protista, Fungi, Plantae, and Animalia.
Protozoa are commonly defined as
eukaryotic, non-photosynthetic, absorb or ingest nutrients, motile and unicellular
In the 1940s, penicillin began to be widely used to treat a variety of bacterial infections. At that time, penicillin-resistant strains of S. aureus were virtually unknown. Twenty years later, 80% of hospital-acquired S. aureus were penicillin-resistant, leading to the introduction of methicillin in 1961 to combat penicillin-resistant strains. Within one year, doctors began to encounter methicillin-resistant strains of S. aureus. Since the development of methicillin-resistance, strains of S. aureus have become resistant to beta-lactam drugs (including all the penicillins), as well as some cephalosporins, leaving vancomycin (typically a "drug of last resort") as the favored treatment for antibiotic-resistant Staph infection.In the late 1990s, vancomycin-resistant strains of Staph began to appear. Around that time, oxazolidinones also became available, and linezolid, also a drug of last resort, was introduced as a treatment for S. aureus. Linezolid-resistant strains of Staph were subsequently reported in 2003. The development of multi-drug resistance in Staphylococcus aureus is a classic example of ______.
evolution
Which of the following are symptoms of influenza infection?
fever, muscle pain, headache After the person is exposed to the flu virus, there is a short incubation period—only about one day—before symptoms of infection appear. Influenza infection commonly causes muscle aches and headache. These are most likely due to the fever that is part of the normal immune response to infection. As fever raises the body temperature, cellular demand for water will increase. At the same time, the person's appetite and thirst are typically depressed, leading to decreased consumption of water. These two factors contribute to dehydration and an electrolyte balance, which typically manifest as general malaise and headache.
Plasmodium sp.
example of a sporozoa that can cause disease causes malaria
Penicillin is an antibiotic widely useful against gram-positive and gram-negative bacteria
false
you take a sample of pus from your patient's abscess for analysis. Results from Gram-staining are shown here:What does this result show?
gram-positive, spherical bacteria
Based on the observed effect of UV radiation on microbes, UV radiation is routinely used
for decontamination purposes
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?
genital herpes
Both genital herpes and genital warts are caused by viruses; which one is the greater danger to a pregnancy?
genital herpes > neonatal herpes : can cause abortion or serious fetal damage to skin, mucous membranes and eyes
All common microbes can break down by oxidation or fermentation the following compound
glucose
One of the tests performed in the lab involves the formation of a red compound as a ring in the surface of the medium. This is the test to detect
glucose
In fermentation tests, you used medium with the following substrates
glucose, sucrose, lactose
bordella
gram negative pleomorphic rod
Haemophilus
gram negative rod
Cornyebacterium
gram positive rod
Beta-hemolytic streptococci
gram-positive bacteria that, when grown on blood-agar plates, completely hemolyze the blood and produce a clear zone around the bacteria colony. Group A beta-hemolytic streptococci cause disease in humans. usually precedes glomerulonephritis and rheumatic fever S.pyogenes ans S. agalctiae
HAV
hepatitis A virus
Which of the following causes inflammation of the liver?
hepatitis A virus
HBV
hepatitis B virus
Vaccines can be used to protect at-risk individuals from all of the following liver diseases EXCEPT __________.
hepatitis C NO VACCINE
HIV
human immunodeficiency virus HIV damages your immune system because it targets CD4 cells. The virus grabs on to the surface of a cell, gets inside, and becomes a part of it. When the infected CD4 cell dies, it releases more copies of HIV into the bloomstream.
Which bond is best described as an intermolecular attraction due to partial charges formed in polar covalent bonds? -covalent bonds -hydrophobic bonds -ionic bonds -hydrogen bond
hydrogen bonds A hydrogen bond is an attraction between hydrogen and more electronegative atoms that are themselves involved in polar covalent bonds. Polar covalent bonds can result in partial charges and the attraction of molecules with opposite partial charges.
The qualitative analysis of water has the objective of determining
if coliform bacteria are present in water samples
Predict which of the following are reasonable outcomes of the cytokine storm during the 1918 flu pandemic.
increased fluid in the lungs and labored breathing an excessive inflammatory response leading to extensive tissue damage The cytokine storm during infection with the 1918 influenza was extremely destructive. The massive release of cytokines in the lungs led to an uncontrolled inflammatory response. As cells moved into the lung tissue, the tissue was destroyed. Fluid entered the lungs, and patients struggled to breathe. Furthermore, the ability to deliver oxygen to the body was severely compromised, giving many patients a blue appearance.
Which type of bond is found between Na+ and Cl- ions in NaCl?
ionic bond
Chikungunya
is spread via mosquitoes, particularly those in the genera of Aedes.
Why can the antibiotic chloramphenicol readily cross the blood-brain barrier, whereas most other antibiotics cannot
it can cross because it is lipid soluble.
common cold
it is transmitted via aerosols and contact. it is caused by rhinoviruses and coronaviruses. the duration of symptoms is approximately one week. complications include laryngitis and otitis media.
leukocidin
lyses neutrophils and macrophages destroys WBC
What carries instructions for making proteins from the nucleus into the cytoplasm?
mRNA The "m" in mRNA stands for "messenger"; mRNA is the messenger that carries genetic instructions from the nucleus to the cytoplasm.
Bacterial encephalitis and meningitis are difficult to treat because
many antibiotics cannot penetrate the blood-brain barrier.
Infants born to asymptomatic mothers with recurrent genital herpes are less likely to acquire herpesvirus at birth than infants born to newly infected mothers because
maternal antibodies offer protection.
Organisms like E.coli and Staphylococcus aureus, part of our normal microbiota, are
mesophiles
The use of a selective medium is necessary to establish the presence of coliforms in water because
of all of the gas-producing bacteria, you are only interested in the gram-negative ones
All of the following are characteristic of the Group A beta-hemolytic streptococci EXCEPT
methicillin resistance.
Which of the following is used to treat candidiasis of the skin or mucous membranes?
miconazole
A driving force of this sort of evolution is ___________, which is sometimes colloquially referred to as the "survival of the fittest."
natural selection
Which of the following is part of the endomembrane system?
nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles and the plasma membrane. GOGLI It manufactures, processes, and transports lipids and proteins. The Golgi apparatus processes and packages proteins.
Warts are caused by
papillomavirus. (HPV)
How might the use of penicillin result in a case of candidiasis?
penicillin would suppress normal microbiata allowing C. albicans to overgrow
On October 5, a pet store sold a kitten that subsequently died. On October 22, rabies was diagnosed in the kitten. Between September 19 and October 23, the pet store had sold 34 kittens. Approximately 1000 people responded to health care providers following local media alerts. These people were given
postexposure prophylaxis.
Animal parasites
present a variety of macroscopic and microscopic structures
Scarlet fever
produced by the erythrogenic toxin produced by Streptococcus pyogenes.
Vibrio cholerae (Cholera)
produces a toxin that makes Gprotein stay in active form. It continues to make cAMP and that causes GI cells to secrete salt into intestines. deathly once person loses too much water and salt infect the GI tract remains outside the eipothelial cells rehydration and azythromycin
Which one of the following is responsible for epidemics of respiratory disease in infants?
respiratory syncytial virus
Exfoliative toxin is responsible for
scalded skin syndrome.
Exotoxins
secreted and cause disease even if the prokaryotes that produce them are not present
SARS
severe acute respiratory syndrome
STI's
sexually transmitted infections
transmitted via the respiratory route
smallpox. measles. chickenpox. rubella. Haemophilus influenzae. Cryptococcus neoformans. Neisseria meningitidis.
Where are lipids made in the cell?
smooth endoplasmic reticulum (ER)
What body fluid is sampled to diagnose bacterial meningitis?
spinal fluid
Now that you have considered the evidence at hand, you should start to build a hypothesis about what disease your patient has. In the beginning of your diagnostic process you should try to think broadly and consider any and all reasonable possibilities. You can then narrow down these possibilities by performing diagnostics that can support or refute your hypothesis.
staphylococcal skin infection (folliculitis, impetigo, scalded skin syndrome, toxic shock syndrome) streptococcal skin infection (necrotizing fasciitis, erysipelas) acne
Much of the energy released in catabolic reactions is captured in ATP for use in other reactions. When the phosphate is transferred directly from an organic molecule to ADP in order to produce ATP without an energized membrane, what has occurred?
substrate-level phosphorylation This is the case when the phosphate is transferred from a substrate to ADP.
What is the common name for otitis externa?
swimmers ear
Naegleria fowleri meningoencephalitis is commonly acquired by
swimming in warm ponds or streams.
When a sugar fermentation tube medium changes color after inoculation and incubation and the glass bell does not show a bubble inside, we can conclude that
the microbe degrades the sugar without producing gas
All of the following are transmitted via the respiratory route EXCEPT
tinea
Characteristics of Group A beta-hemolytic streptococci
the ability to dissolve blood clots. the ability to damage cell membranes. M proteins. hyaluronidase production.
What was the MOST likely source of the family's botulism food poisoning?
the family consumed botulism toxin in the canned green beans.
The efficacy of a compound against a certain microbe can be determined by
the measurement of the zone of inhibition
After reviewing your patient's medical history, you decide to list out the factors that you think will be most important to your diagnostic process.
the patient's symptoms the fact that the bite did not respond to treatment with antibiotic ointment the fact that more than one person had similar symptoms the patient's activities before and during the infection
Detection of gas in fermentation tubes in the last step of water quality implies
the presence of coliforms in the original sample
hemolysis
the rupture or destruction of red blood cells.
One of the most apparent features of fungi is that
they are not green, they completely lack chlorophyll and thus are heterotrophic many produce large black masses of spores
mesophiles
those growing best between 20 degrees and 40 degrees celcius; the human pathogens are in this group NORMAL MICROBIOTA LOVING MODERNATE TEMERPERARURE
Simmons' citrate agar is used
to detect bacteria that use citrate as a sole source of carbon
A patient comes in with a possible Chikungunya infection. Rank the following in order.
uninfected mosquito feeds on an infected person replication of the virus Inside the vector infected mosquito feeds on uninfected person patient has fever, headaches, and joint pain treatment with supportive therapy In order for a mosquito to acquire the virus and be infectious, it must first take a blood meal from an infected individual. Once the virus gets into the mosquito, it must replicate and form new virus particles. These virus particles are now spread to a new uninfected host. This individual will begin to exhibit signs and symptoms within a week of being bitten by the mosquito. At this time, there are no antivirals available, so treatment is to give supportive therapy for the signs and symptoms. Patients are advised to get plenty of rest, drink plenty of fluids, and to take over-the-counter medications for fever and pain.
Which of the following eukaryotic organelles is correctly matched with its function?
vacuole--storage of materials Vacuoles provide storage for many important cellular substances.
A woman just found out that she is pregnant. As a first-time mother-to-be and student in microbiology, she is worried about all the different microbes that could potentially harm her unborn child. What is the term used to describe the transmission of microbes from mother to fetus via the placenta or during delivery?
vertical transmission
Now that we have looked at ways to prevent breeding in mosquitos, another possible prevention is to limit the vector geographically, but recent climate changes have led to changes in location where the mosquito can now be found. Which of the following climate change scenarios has allowed for this increase in vector habitat?
warmer temperatures in northern regions with increased rainfall Rising temperatures and increased rainfall has increased the population of Aedes mosquitoes in the more Northern parts of the United States. It is predicted that the increases in annual temperatures and the average rainfall will lead to migration of the mosquito to areas of the world that were previously uninhabited by these mosquitoes. The increase of their numbers in this geographic location also increases the incidence of any infectious disease that the mosquito might be harboring. This has been shown with viruses such as Dengue and West Nile. It is predicted that the numbers of Chikungunya will also increase because of the migration of these vectors.