Exam 4- Sarah Browne Microbiology study guide Ch 21-25

What is the name of the bacteria that causes Lyme disease?

Borrelia burgdorferi

What is relapsing fever?

Borrelia recurrentis, transmitted to humans via body louse. Occurs in africa and south america. It is characterized by recurring episodes of septicemia and fever due to the body repetitive efforts to remove the spirochetes.

Chlamydia pneumoniae causes?

Bronchitis, pneumonia, and sinusitis

What is the most common cause of bacterial gastroenteritis in the United States.

Campylobacter jejuni

In the United States, there are two primary tick vectors:

Dermacentor andersoni (in the western United States) and Dermacentor variablis (in the eastern United States)

What is the preferred treatment for Rickettsia prowazekii ? How is it prevented?

Doxycycline or chloramphenicol and tetracycline Prevented with good personal hygiene and a vaccine is available for high risk populations.

After a human is bitten by a rabies infected animal, where does the virus replicate? Name the complete mode of transmission

It replicates in the muscle near the bite, then the virus moves up the PNS to the CNS in the spinal cord, virus moves up the spinal cord where is reaches the brain and causes fatal encephalitis, finally the virus enters the salivary glands and other organs of the bite victim

Rickettsia prowazekii doesn't live long enough on humans to reproduce, how does it make a person sick?

It transmits bacteria to the human

This gram negative pathogenic Vibrio colonizes the stomach of it host, is obtained from ingestion of bacteria from contaminated hands, well water or fomites. It causes gastritis and most peptic ulcers. Treatment with antibiotics ↓ death and morbitity.

Helicobacter pylori

If a person is infected with Ehrlichia chaffeensis, what leukocyte is it infecting?

Human Monocyte

What is the primary host for Rickettsia prowazekii

Humans

What other area of the body besides the reproductive system does Chlamydia trachomatis affect?

It is also a major cause of eye infections worldwide. Blindness can occur but be prevented with prompt use of antibacterial agents

Most human infections are cause by three species of Rickettsia, Name them.

Rickettsia rickettsii, R. prowazekii and R. typhi

This disease is a tickborne disease caused by Rickettsia rickettsii

Rocky mountain spotted fever. The most severe of the tick borne rickettsial diseases

Gumma

Rubbery, painfully swollen lesions that can occur in bones, in nervous tissue, or on the skin

SLE Stands for? transmitted by?

Saint louis Encephalitis (SLE) transmitted via squirrels and chipmunks

why would a patient end up with DIC during a sepsis infection?

Sepsis triggers Platelet activating factor (TNF II also)

An Ixodes tick lives for two years, during which it passes through three stages of development: what are the stages?

Stage 1-a six-legged larva Stage 2- an eight-legged nymph Stage 3- an eight-legged adult. During each stage it attaches to an animal host for a single blood meal. After each of its three feedings, the tick drops off its host and lives in leaf litter or on brush.

What are the two agents (causes) of Bacterial Endocarditis?

Staphylococcus aureus and Streptococcus pneumoniae

The cyclical waves of parasitemia associated with Trypanosoma brucei infections are related to?

antigenic variation Trypanosoma brucei constantly changes its surface antigens, thereby persistently eluding the immune system.

Reovirus

are respiratory and enteric viruses with naked icosahedral capsids. They are unique in being the only microbes, viral or cellular, with genomes composed of double-stranded RNA (dsRNA). Each virus contains 10 to 12 segments of dsRNA.

The lower respiratory tract consists of?

bronchi lungs pleura trachea

Identify the diseases caused by Ehrlichia and Anaplasma

cause human monocytic ehrlichiosis (HME) and anaplasmosis

What are some common signs of septicemia?

Petechiae and splinter hemorrhage formation. A systemic inflammatory response syndrome can occur (SIRS)

When do Tick larvae become infected?

Spring time-During their first blood meal. Over the winter, larvae digest their blood meals while Borrelia replicates in the ticks' guts

What are the agents that cause sub-Acute Bacterial Endocarditis?

Staphykococcus epidermidis, Viridans Alpha hemolytic streptococci and enterococci.

What are the most common agents of SBE?

Staphylococci, Streptococci and Enterococci.

A patient exhibiting arthritis secondary to Lyme disease is likely in which phase of the infection? First, second, third or fourth?

Third

How does Chlamydia trachomatis enter the body?

Through abrasions and lacerations and infects the conjuctiva and various mucus membranes

What kind of tick causes Ehrlichia and Anaplasma?

Ticks, including the Lone Star tick , the deer tick (Ixodes), and the dog tick (Dermacentor), transmit Ehrlichia and Anaplasma to humans

Anaplasma phagocytophilum, a gram negative intracellular bacterium is the agent found in which tick borne diesase? What family is it found in? Which WBC does it affect?

- Human Granulocytic anaplasmosis (HGA) - Ehrlichia family - Neutrophils

How are the diseases confirmed? What is the desired treatment for HME and HGA?

- Immunofluorescent antibodies against Ehrlichia or against Anaplasma can demonstrate the bacterium within blood cells, confirming the diagnosis. -Doxycycline and tetracycline are effective against both Ehrlichia and Anaplasma, but chloramphenicol is not.

Chlamydia psittaci causes? What is it? What is the treatment?

- Ornithosis - Disease of a bird that can be transmitted to humans via inhalation of aerosols or contact with infected bird feces or the actual bird. - Tetracycline or azithromycin

West nile virus is also known as? What are the two forms?

-Flavivirus= Itis transmitted via mosquito's that have fed on infected birds. The mosquito bites a human or a horse and the virus spreads to the brain - West nile fever and West nile encephalitis

How do doctors diagnose all three forms of non venereal syphilis? What is the desired treatment for all Bejel, Yaws and Pintas?

-Physicians diagnose bejel, yaws, and pinta by their distinctive appearance in children from endemic areas. Clinicians can not detect spirochetes in specimens from the lesions of bejel, but they are present in patients with pinta and yaws. -Penicillin is the most favored antimicrobial agent for treat-ing these three tropical diseases. Prevention involves limiting the spread of the bacteria by preventing contact with the lesions.

What is a secondary infection

A secondary infection is defined as an infection caused by an opportunistic microbe after a primary infection has weakened the host's defenses. Yeast infections are common secondary infections after antibiotic treatment for a primary bacterial infection.

Lyme disease is characterized by- It is treated with?

-dermatological (bulls eye rash, aka Erythema migrans)malaise, headaches, dizziness, stiff neck, severe fatigue, fever, chills, muscle and joint pain, and lymphadenopathy. cardiac and neurological abnormalities (Heart and nervous system impairment 2-8 weeks after rash appears). Neurological symptoms (e.g., meningitis, encephalitis, and peripheral nerve neuropathy) and cardiac dysfunction typify the second phase, which is seen in only 10% of patients. The final phase is characterized by severe arthritis that can last for years. In addition to the observed arthritis. Infected children may have paralysis of one side of their face (Bell's palsy). 2- Antimicrobial drugs effectively treat the first stage of Lyme disease

Prion define Spongioform encepaphalopathies-

-lack instructional nucleic acid. Prusiner named such agents of disease prions, for protein-aceous inefctive particles. -that prion PrP acts like a bad influence in a crowd of teenagers, encouraging molecules of normal, cellular PrP to misbehave by refolding into prion PrP molecules, which then clump together. As clumps of prion PrP propagate throughout the brain, neurons stop working properly and eventually die, leaving holes and a spongy appearance. Because of this appearnce scientists named it spongiform encephalopathies Copyright | Benjamin Cummings | Microbiology with Diseases by Taxonomy | Edition 4 | [email protected] | Printed from www.chegg.com

Rickettsia typhi causes? The major reservoir for the bacterium is? What are the vectors for this disease? What treatment is used?

-murine typhus, - the major reservoir for the bacterium is rodents - Rodent Fleas - Doxycycline or chloramphenicol

1) Which of the following factors would NOT contribute to the development of severe dermatomycoses? 1- corticosteroids for asthma control 2- diabetes mellitus 3- wearing sandals 4- HIV coinfection 2) How can this disease best be categorized? 1-zoonotic and noncommunicable 2-noncommunicable and chronic 3-contagious and chronic 4-acute and contagious

1) 3- wearing sandals 2) 3-contagious and chronic

1- Which kind of Bacterial endocarditis is rapid and progressive and caused by more virulent organisms? 2- This form of Bacterial endocarditis is slow and progressive and caused by less virulent organisms

1- Acute Bacterial Endocarditis 2- Subacute bacterial endocarditis

Which of the following types of immune cells is directly responsible for antibody synthesis? 1- B- lymphocytes 2-helper T lymphocytes 3-cytotoxic T lymphocytes 4-macrophages

1- B- lymphocytes

How do blastoconidia and chlamydoconidia produced by yeast differ from bacterial endospores? 1- Blastoconidia and chlamydoconidia are spore structures produced by budding in yeasts, whereas bacterial endospores are produced by bacteria under extreme conditions. 2- Blastoconidia and chlamydoconidia are produced only by yeasts in extreme conditions, whereas bacterial endospores are asexual reproductive structures. 3- Blastoconidida and chlamydoconidia are identical to endospores. 4- Blastoconidia and chlamydoconidia are male and female mating structures used for reproduction in yeasts, whereas bacterial endospores are asexual reproductive structures.

1- Blastoconidia and chlamydoconidia are spore structures produced by budding in yeasts, whereas bacterial endospores are produced by bacteria under extreme conditions.

1- How do humans get Cholera? 2- where is it found? 3-What is a characteristic of the stool infected with cholera? 4- what is the most important virulence factor associated with cholera? 5- What does this virulence factor do to the body? 6- How is it diagnosed? 7- How is it treated? 8- How is it prevented?

1- By ingesting contaminated food and water 2- found mostly in areas with poor sewage and water treatment 3- rice-water stool 4- Cholera toxin- shuts protein synthesis down 5- causes severe loss of fluid and electrolytes 6- Based on characteristic diarrhea 7- Fluid and electrolyte replacement 8- proper sewage and water treatment and an oral vaccine provides some protection

Which of the following can produce blindness, especially in children? 1- Chlamydia trachomatis 2- Chlamydophila psittaci and Chlamydia trachomatis 3- Chlamydophila pneumoniae 4- Chlamydophila psittaci

1- Chlamydia trachomatis

1- What are the symptoms of HHV 1? 2- Herpetic pharyngitis

1- Cold sores and fever blisters, Herpetic pharyngitis and esophagitis. 2- Young adults with sore throats resulting from other viral infections may also develop herpetic pharyngitis.

Which of the following statements best describes why the treatment for Tori's fungal infection may result in side effects to her own cells? 1- Fungal cells and human cells have a nucleus, multiple organelles, and 80S ribosomes for protein synthesis. 2- Fungal cells and human cells both reproduce via budding. 3- Fungal cells and human host cells both have cell walls made of cellulose. 4- Fungal cells and human host cells both have flagella for movement.

1- Fungal cells and human cells have a nucleus, multiple organelles, and 80S ribosomes for protein synthesis.

1-What kind of tick transmits R. rickettsii to humans and rodents? 2-Where in the tick is the disease found? 3-When does the bacteria become activated?

1- Hard ticks in the genus Dermacentor 2- Dormant in the salivary glands 3- After the arachnid feeds for several hours, active bacteria are released into the circulatory system of the mammalian host where they infect endothelial cells lining the small blood vessels

Untreated syphilis has four phases: primary, secondary, latent, and tertiary syphilis. Describe each phase 1- primary syphilis, 2- Secondary syphilis 3- Latent Syphilis 4- Tertiary Syphilis

1- Primary Syphilis starts with a small, painless, reddened lesion called a chancre, forms at the site of infection 10 to 21 days following exposure. Although chancres typically form on the external genitalia, about 20% form in the mouth, around the anus, or on the fingers, lips, or nipples. 2- Secondary Sphyilis- The bacteria has envaded the blood stream and spreads throughout the body to cause the symptoms and signs of secondary syphilis: sore throat, headache, mild fever, malaise, myalgia , lymphadenopathy (diseased lymph nodes), and a widespread rash that can include the palms and the soles of the feet. 3- Latent phase, most cases of syphilis do not advance beyond the secondary phase. After a few weeks the lesion disappears and the disease and the patient enters a latent (clinically inactive) phase of the disease. especially in developed countries where antimicrobial drugs are in use. Latency can last 30 plus years. 4- Tertiary phase-This phase is associated not with the direct effects of Treponema but rather with severe complications resulting from inflammation and a hyper-immune response against the pathogen. Tertiary syphilis may affect virtually any tissue or organ and can cause dementia, blindness, paralysis, heart failure, and syphilitic lesions called gummas , which are rubbery, painfully swollen lesions that can occur in bones, in nervous tissue, or on the skin

What are the order of events that occur during RMSF infection?

1- Tick bite transmits R. rickettsii into the blood stream 2-R. rickettsii travels through-out the body via the blood and lymph systems 3-R. rickettsii invades endotheilial cells of the blood vessels 4- R. rickettsii multiplies within host cells 5- Symptoms such as a macular rash develop (bulls eye rash)

Rickettsias are obligate parasites of other cells probably because they cannot retain small cofactors needed for independent metabolism. 1- True 2- False

1- True Rickettsias can synthesize ATP, but they may have a problem retaining small cofactors such as NAD+ because of their "leaky" cytoplasmic membranes

Chlamydias parasitize other cells because they cannot manufacture ATP. 1- True 2- False

1- True- Chlamydias lack the enzymes necessary to be able to synthesize ATP

1- What other disease of Vibrio results from ingestion of shellfish? 2- What does it cause?

1- V. parahaemolyticus 2- causes cholera like gastroenteritis

1- What other disease of Vibrio results from ingestion of contaminated shellfish or washing hands with contaminated seawater? 2- what does it cause?

1- V. vulnificus 2- Septicemia- which can be fatal if left untreated

Resistance to malaria is increased by all of the following EXCEPT _____. 1-presence of hemoglobin A 2-sickle-cell trait 3-a lack of Duffy antigens on erythrocytes 4- glucose-6-phosphate dehydrogenase deficiency

1- presence of hemoglobin A; This provides some protection against infection by Plasmodium; for some unknown reason, humans with two genes for hemoglobin C (not A) are protected against malaria

The IV regimen administered by Ron's doctors is consistent with the CDC's recommendation that doxycycline be administered when RMSF is suspected. Apply your knowledge of RMSF to choose the most likely reasons behind this recommendation. Select all that apply. 1-A delay in treatment can lead to complications that include respiratory, cardiac, and renal failure. 2- Most tests that can definitively identify R. rickettsii are not very effective early in infection. 3-Doxycycline is an effective treatment for most infections transmitted by vectors. 4-At the very least, treatment with doxycycline will slow the progress of the infection and allow the physicians adequate time to make a definitive diagnosis. 5-The symptoms of RMSF are similar to those of several other infections, making definitive diagnosis difficult. 6-Without prompt treatment, RMSF can have a mortality rate as high as 20%.

1-A delay in treatment can lead to complications that include respiratory, cardiac, and renal failure. 2- Most tests that can definitively identify R. rickettsii are not very effective early in infection 5-The symptoms of RMSF are similar to those of several other infections, making definitive diagnosis difficult. 6-Without prompt treatment, RMSF can have a mortality rate as high as 20%.

1-What kind of vector transmits all three species of Rickettsia? 2-How do these vectors enter the host cell? 3-Once inside the cell what do the microbes do?

1-Arthropods 2- By stimulating endocytosis 3- They secrete an enzyme that digests the membrane of the endocytic vesicle, releasing the bacteria into the cytosol. As a result, rickettsias avoid the lysis that would ensue if a lysosome had merged with the endosome

Mushrooms are structures associated with which of the following divisions of fungi? 1-Basidiomycota 2-Ascomycota or Zygomycota 3-Zygomycota 4- Ascomycota

1-Basidiomycota Mushrooms are the spore-bearing reproductive structures of certain members of the division Basidiomycota

1- What is the likely most common cause of gastroenteritis in the untied states? 2- What serves as a reservoir for C. jejuni? 3- How are humans infected and what is the most common source? 4- What do the infections produce?

1-Campylobacter jejuni (pathogenic gram neg vibrio) 2-many animals 3- consuming contaminated food, milk or water and poultry is the most common source 4- self limiting and bloody diarrhea

1-Cytomegalovirus (CMV) 2- How is CMV transmitted? 3-

1-HHV5, very harmful to fetuses, transplant recipients and people with HIV 2- in bodily secretions, including saliva, mucus, milk, urine, feces, semen, and cervical secretions. Transmission usually occurs via sexual intercourse but can result from in utero exposure, vaginal birth, blood transfusions, and organ transplants. CMV infects 7.5% of all neonates, makng it the most prevalent viral infection in this age-group. 3-

Which of the following is a characteristic of biological transmission from Dermacentor to a human host? 1- The human host is infected after drinking water contaminated with Dermacentor eggs. 2- R. rickettsii is transmitted to the human host during a bite, when tick saliva enters the wound. 3- R. rickettsii is transmitted to the human host after the human consumes food that the tick has contacted. 4- R. rickettsii is transmitted to the human after the human drinks water that has been contaminated by feces from an animal infected with Dermacentor spp.

2- R. rickettsii is transmitted to the human host during a bite, when tick saliva enters the wound.

What kind of immune response occurs during Lyme disease? Why?

An adaptive immune response Since antibodies are used in the diagnosis of the disease, there must be an adaptive immune response

An indirect immunofluorescence assay is described as the CDC "gold standard serological test" for RMSF. Keeping in mind the principles behind indirect fluorescent-antibody (indirect FA) testing, which of the following characteristics contributes to its choice as the gold standard? Select all that apply. 1-Indirect FA uses an antibody that reacts with any human antibody. 2-Indirect FA will detect R. rickettsii-specific antibodies present in the patient's serum. 3-Indirect FA is rapid, sensitive, and specific. 4-Indirect FA is more sensitive than direct immunofluorescent testing. 5-Indirect FA will detect antigens present in the patient's serum. 6-Indirect FA requires an antibody that is specific for R. rickettsii.

1-Indirect FA uses an antibody that reacts with any human antibody. 2-Indirect FA will detect R. rickettsii-specific antibodies present in the patient's serum. 3-Indirect FA is rapid, sensitive, and specific. 4-Indirect FA is more sensitive than direct immunofluorescent testing.

Leptospira interrogans 1- What does it look like? 2- Where is it found? 3- How does it enter the body? 4- how does it travel in the body? 5- What can it cause? 6- how is it treated? 7-Is there a vaccine?

1-Spiral shaped and one end of the spirochete is hooked in a manner reminiscent of a question mark. 2- In numerous wild life and domestic animals 3-Skin or mucus membranes 4- via the blood stream 5-Hemorrhaging, liver and kidney disfunction 6- IV PCN 7- only for pets and live stock, not for humans

1- Arbovirus 2- Arboviral encephalitis is transmitted via?

1-The word arbovirus is an acronym (ARthropod-BOrne virus) 2-an abidgial vector such as a mosquito. Biological vector transmission

Chlamydia trachomatis infections often mimic infections of Neisseria gonorrhoeae. 1-True 2-False

1-True

1-WEE/EEE/VEE-What do they stand for? 2-Of these three which is the most deadly?

1-Western, Eastern and Venezulan Equine Encephalitis (horses). 2-EEE

Apicomplexans are members of which of the following groups of protozoa? 1-alveolates 2-amoebae 3-diplomonads 4-euglenids

1-alveolates Examples of apicomplexans are the genera Plasmodium and Toxoplasma

Lymphogranuloma venereum is associated with infections of which of the following? 1- Treponema pallidum pertenue 2- Chlamydia trachomatis 3- Chlamydophila pneumoniae 4- Campylobacter jejuni

2- Chlamydia trachomatis

Which of the following causes the most common reportable sexually transmitted disease in the United States? 1- Chlamydophila pneumoniae 2- Chlamydia trachomatis 3- Ehrlichia chaffeensis 4- Chlamydophila psittaci

2- Chlamydia trachomatis

Diagnosis of anaplasmosis and human monocytic ehrlichiosis is facilitated by the distinctive symptoms of these diseases. 1- True 2- False

2- False

Aflatoxin exposure can cause which of the following? 1-convulsions 2-liver cancer 3-allergic reactions 4- hallucinations

2- Liver cancer Aflatoxins, produced by the ascomycete Aspergillus, are carcinogenic at low levels, and can cause liver damage and liver cancer.

Which of the following infections are also caused by C. albicans? Select all that apply. 1- genital warts 2- oral thrush 3- syphilis 4- fulminating disease

2- Oral thrush 4- Fulminating disease **Candida albicans is also the causative agent of oral thrush and fulminating disease. Infants are prone to thrush because they come in contact with the yeast as part of mom's normal flora when nursing. Fulminating disease, which most often afflicts immunosuppressed individuals, results when the yeast enters the bloodstream and travels throughout the entire body, resulting in a systemic infection. Individuals suffering from AIDS are susceptible to this type of infection.

All of the following are pieces of evidence supporting the cellular nature of rickettsias EXCEPT __________. 1- they contain functional ribosomes 2- they contain DNA and RNA 3- they have a typical bacterial cell wall 4- they reproduce via binary fission

3- they have a typical bacterial cell wall

Tori, a 24-year-old graduate student, had been suffering from a respiratory infection for over a week. She went to the student health center, where the physician prescribed her a broad-spectrum antibiotic. By the end of her round of antibiotics, Tori was no longer suffering from respiratory complications, but she had noticed an increase in itchiness in her genital region. Within a few days, the itchiness was getting worse and was accompanied by a vaginal discharge that had a cheesy consistency and foul odor. Tori returned to the student health center to discuss her condition with the physician. A sample of her discharge was taken and sent to the laboratory for microscopy and plating. Why did tori develop a secondary infection? 1- Tori's immune system was compromised because of her respiratory infection, and this resulted in a yeast infection. 2- The antibiotics that treated Tori's primary respiratory infection also removed some of her normal bacterial flora, resulting in an overgrowth of other organisms. 3- Tori contracted a sexually transmitted infection that was not related to the primary respiratory infection. 4- The initial antibiotics were not successful in clearing the respiratory infection, so the organism disseminated to the genitourinary tract

2- The antibiotics that treated Tori's primary respiratory infection also removed some of her normal bacterial flora, resulting in an overgrowth of other organisms.

Which of the following is NOT a characteristic of all apicomplexan parasites? 1-They form nonmotile, spore-like shapes. 2- They infect the bloodstream. 3- They are parasites of animals. 4- They require two types of hosts to complete their life cycles.

2- They infect the bloodstream.

Which of the following is the LEAST useful tool in the diagnosis of fungal infections? 1- growth on Sabouraud dextrose agar 2- direct immunofluorescence stain 3- KOH preparations 4-Gomori methenamine silver stain

2- direct immunofluorescence stain Because fungi are so prevalent in the environment and as part of the normal microbiota, immunological tests are the least useful means of distinguishing infection from simple exposure.

Spirochetes can be isolated during all phases of syphilis. 1- True 2- False

2- false

The cellular immune response is focused primarily on the presence and activity of which of the following? 1-B lymphocytes 2-T lymphocytes 3-complement proteins 4-interferons

2-T lymphocytes- The cellular immune response is focused primarily on the presence and activity of T lymphocytes; in contrast, the humoral immune response involves the activity of B lymphocytes.

Which of the following is part of the immune system's specific defense mechanism against virus-infected cells? 1-helper T lymphocytes 2-cytotoxic T lymphocytes 3-macrophages 4-B lymphocytes

2-cytotoxic T lymphocytes Cytotoxic T cells kill virus-infected cells, thereby preventing the spread of viruses to other cells.

Which of the following does NOT describe helminths? 1-macroscopic 2-routinely parasitic 3-eukaryotic 4-multicellular

2-routinely parasitic

Which of the following does NOT describe helminths? 1-macroscopic 2-routinely parasitic 3-eukaryotic 4-multicellular

2-routinely parasitic Helminths are macroscopic, multicellular, eukaryotic worms, only some of which enter into parasitic associations with other animals.

Which of the following is a type of asexual reproduction that is characteristic of some parasitic protozoa? 1-binary fission 2-schizogony 3-meiosis 4-conjugation

2-schizogony

Which of the following types of histoplasmosis can be fatal? 1- ocular histoplasmosis 2- systemic histoplasmosis 3- chronic cutaneous histoplasmosis 4- chronic pulmonary histoplasmosis

2-systemic histoplasmosis Systemic histoplasmosis, a severe form of the disease that can result in death, is usually only seen in AIDS patients.

Pseudohyphae are associated with which of the following opportunistic fungi? 1- Aspergillus 2- Cryptococcus 3- Candida 4- Pneumocystis

3- Candida

Which of the following pathogens is incorrectly matched with the biological vector that transmits it? 1- Orienta tsutsugamushi - mites 2- Rickettsia prowazekii - lice 3- Rickettsia typhi - rodents 4- Rickettsia rickettsii - hard ticks

3- Rickettsia typhi - rodents

How do pseudohyphae in yeasts differ from vegetative hyphae in filamentous fungi? 1- Yeasts use pseudohyphae as a means of sexual reproduction, whereas parasitic fungi use their hyphae to invade host tissue. 2- Yeasts use pseudohyphae for obtaining nutrients, whereas filamentous fungi use their vegetative hyphae to invade host tissues. 3- Yeasts use pseudohyphae to invade host tissue, whereas filamentous fungi use their vegetative hyphae for obtaining nutrients. 4-Yeasts use pseudohyphae as a means of obtaining nutrients, whereas filamentous fungi use vegetative hyphae as a means of reproduction.

3- Yeasts use pseudohyphae to invade host tissue, whereas filamentous fungi use their vegetative hyphae for obtaining nutrients.

Lyme disease __________. 1- is caused by a bacterium that can only survive in a human host 2- is spread to humans by mosquito bites 3- causes 75% of patients to have bull's-eye rash, can produce neurological symptoms, and can induce severe arthritis lasting years 4- is caused by the bacterium Vibrio cholera

3- causes 75% of patients to have bull's-eye rash, can produce neurological symptoms, and can induce severe arthritis lasting years

The symptoms of Rocky Mountain spotted fever are a result of __________. 1- the host immune response against Rickettsia rickettsii 2- rickettsial toxins 3- damage to blood vessels 4- the host immune response against the tick vector

3- damage to blood vessels

What is babesiosis?

A protozoan tick borne malarial like illness that infects RBC's and causes fatigue, aches, pains, chills, dark urine and an enlarged spleen

Rickettsia rickettsii is a gram-negative, obligate intracellular parasite. Which of the following statements about the R. rickettsii life cycle is FALSE? 1-Like viruses, R. rickettsii requires a eukaryotic host in order to carry out its life cycle. 2-In order to cause RMSF, R. rickettsii must enter host cells. 3-After entering a host, R. rickettsii multiplies to levels high enough to successfully invade cells and establish an infection. 4-During infection, R. rickettsii is able to survive and replicate within eukaryotic cells.

3-After entering a host, R. rickettsii multiplies to levels high enough to successfully invade cells and establish an infection.

Which of the following groups of opportunistic fungi is associated with buildings where birds roost near air-intake vents? 1-Candida 2-Aspergillus 3-Pneumocystis 4- Cryptococcus

4- Cryptococcus Human infections of Cryptococcus are caused by the inhalation of spores or dried yeast in aerosols from the droppings of birds that roost near building air-intake vents.

The infective stage of most protozoans is the __________. 1-trophozoite 2-gamete 3- endospore 4- cyst

4- Cyst The dormant cyst stage survives in the environment and is the infective form of most protozoan parasites.

All of the following are true about the cholera toxin EXCEPT __________. 1- it activates host cell cAMP, which causes the secretion of excess electrolytes from the cell 2- it produces a hyptertonic intestinal lumen, which causes water to flow out of the cells producing diarrhea 3- it is an example of an A-B toxin, containing A and B subunits 4- it forces water out of the host cell

4- it forces water out of the host cell

Which of the following is NOT a characteristic of the elementary bodies that cause chlamydia infections? 1- resistant to environmental extremes 2- infective forms 3- dormant 4- replicate inside phagosomes

4- replicate inside phagosomes

A 30-year-old man comes into a community clinic complaining of persistent redness, itching, and peeling skin on the soles of his feet and between his toes. He states that he works out daily and plays on several sports teams. He concluded he has athlete's foot, but every over-the-counter antifungal agent he has tried has failed to cure his condition. He has finally come to the clinic because his toenails have begun to thicken, yellow, and detach from the nail bed. His condition is pictured. What would be the most effective oral agent to use for treating the condition depicted in this case? 1- clotrimazole 2- amphotericin B 3- ampicillin 4- terbinafine tablets

4- terbinafine tablets

Tsetse flies can carry which of the following pathogens? 1-Giardia intestinalis 2-Plasmodium falciparum 3-Trypanosoma cruzi 4-Trypanosoma brucei

4-Trypanosoma brucei

What is thought to be the major source of Toxoplasma infection for humans? 1-bites from infected arthropods 2-contact with infected cats and their feces 3-sexual activity 4-ingestion of undercooked meat

4-ingestion of undercooked meat

Protozoa are most commonly classified using which of the following characteristics? 1-cell wall composition 2-staining patterns 3-types of reproductive structures 4-mode of locomotion

4-mode of locomotion The major groups of protozoa are differentiated based on their mode of locomotion. They include the ciliates, the amoebae, the flagellates, and the nonmotile apicomplexans.

Which of the following is NOT a suitable means of preventing Rocky Mountain spotted fever? 1-use of tick repellents 2-avoidance of tick-infested areas 3-tight-fitting clothing 4-prophylactic antibiotic use

4-prophylactic antibiotic use

Which of the following is a characteristic of protozoa? 1-cell walls 2-contain cellulose 3-prokaryotic 4-unicellularity

4-unicellularity Protozoa are eukaryotic cells.

How many different types of hepatitis are there? What can they all cause?

6, Hepatitis A,B,C,D,E,F AND G Cause severe liver damage, cirrohis and hepatic cancer

If transmission occurs while the mother is in the latent phase of the disease, the result for the fetus can be?

A latent infection in the fetus that causes mental retarda-tion and malformation of many fetal organs. After birth, newborns with latent infections usually exhibit a widespread rash at some time during their first two years of life.

Virion

A virus outside of a cell, consisting of a proteinaceous capsid surrounding a nucleic acid core.

Organisms infect BOTH deformed and normal heart valves, cause Eboli formatioin

Acute Bacterial Endocarditis

After a primary Herpes I or 2 Infection it goes into a latent stage. Where do they remain?

After a primary infection, these herpes viruses often enter sensory nerve cells and are carried by cytoplasmic flow to the base of the nerve, where they remain latent in the trigeminal, sacral, or other ganglia.

Prion diseases- , Mad cow disease, Variant Creudzfeldt Jacob disease (vCJD) Spongioform encepaphalopathies

Agent of the disease. Abnormal proteins. These are abnormal forms of normal proteins we need.

Congenital Syphilis

An infected mother can transmit Syphilis to her fetus. This can result in mental retardation, malformation and fetal death

what is bacterial endocarditis?

An infection of the inner blood bathed surfaces and valves of the heart

What is the most common form of viral meningitis?and what causes it?

Aseptic meningitis- echoviruses cause viral meningitis and some colds.

Endospores are produced in what kind of conditions?

Harsh conditions

Lyme disease is caused by ____________ and is transmitted by __________

B. burgdorferi; Ixodes

What does septicemia usually start as?

Bacteremia

Why is diagnosis difficult with Human monocytic Ehrlichiosis (HME) and anaplasmosis?

Because the diseases resemble many other illnesses. Physicians consider ehrlichiosis and anaplasmosis in any case of otherwise unexplained acute fever in patients exposed to ticks in endemic regions.

This type of nonveneral syphilis causes Bejel. Describe Bejel-

Bejel is a disease seen in children in Africa, Asia, and Australia and is caused by the T.pallidum endemicum bacteria+. In bejel, the spirochetes are spread by contaminated eating utensils, the initial lesion is an very small oral lesion. As the disease progresses, larger and more numerous secondary lesions form around the lips and inside the mouth. In the later stages of the disease, gummas form on the skin, bones, or nasopharyngeal mucous membranes.

Rickettsia typhi causes ________ typhus, the major reservoir of which is rodents.

Murine

A vaginal sample was taken to the lab. The lab technicians plated a sample of the organism on a nutrient media and on a Sabouraud dextrose agar plate. What yeast would most likely be grown on this kind of media?

Candida albicans-Diagnosis of a yeast infection usually involves patient history, observation of yeast cells via microscopy, and growth of a culture on Sabouraud dextrose agar. Differentiation between yeasts and bacteria is reliant on biochemical characteristics. Differentiation between yeasts and molds is reliant on spore type and function.

What is african sleeping sickness caused by and what is the name of the genus and species

Cause by a bite from a tse-tse fly vector and its called Trypanosoma bruceii

This type of non-venereal syphilis causes Yaws. Describe Yaws.

Caused by T.pallidum pertenue, a disease of tropical South America, central Africa, and Southeast Asia that is characterized initially by granular skin lesions that, although unsightly, are painless. Over time the lesions develop into large, destructive, draining lesions of the skin, bones, and lymph nodes. The disease is spread via contact with spirochetes in fluid draining from the lesions.

Norwalk virus

Causes gastroenteritis mainly in adults. AKA Cruise ship virus

A small, painless sore called a(n)______ is the major sign of primary syphilis.

Chancre

Which is considered the most abundant STD in the USA?

Chlamydias trachomatis

What are the two types of fungal meningitis?

Cryptococcal meningitis and cryptococcus neoformans

Immunization against smallpox was pioneered by which scientist?

Edward Jenner-Jenner pioneered the field of vaccination, also known as immunization, in his research involving smallpox.

Enterovirus causes

Encephalitis and paralysis

ECHO is an acronym for

Enteric Cytopathic Human Orphan, which means it has yet to be classified to a specific sub genus

What are the symptoms of Sub-Acute Bacterial Endocarditis?

Fatigue, tachycardia and slight fever, emboli, stroke and aneurysm

What are two symptoms both forms of SBE have?

Fever and Tachycardia

What does Acute Bacterial Endocarditis cause? (symptoms)

Fever, valve destruction, heart abscesses, heart failure, Tachycardia and stroke

Rotavirus

Gastroenteritis mainly in infants and children and respiratory infections

Which type of septicemia is more severe? and why?

Gram negative is more severe due to endotoxin/Lipid A release.

Give the mode of transmission, the family it herpes comes from, whether it is acute or chronic and if there is a vaccine for these three- Hepatitis A Hepatitis B Hepatitis C

HAV-Fecal/oral transmission, family is picornaviridae, acute hepatitis and its vaccine is a inactivated virrus HBV-Parenteral, STD transmission, Hepadnaviridae, chronic hepatitis, recombinant Vaccine HCV-Parenteral, Filoviridae, chronic and no vaccine available

Which Herpes infects 7.5% of all neonates, mak-ing it the most prevalent viral infection in this age-group.

HHV 5 CMV

Where is Syphilis most contagious and why?

In female syphilis presents mostly on the cervix. A chancre forms and in the center is a pus filled pocket with millions of spirochetes in the pus that makes it highly contagious.

After the Nymphs feed a second time they drop off and undergo further development into adults, what happens then?

In the fall, adult ticks feed a final time, mate, lay eggs, and die

When do the ticks molt into nymphs?

In the spring of their second year and feed a second time, infecting the new hosts with Borrelia via saliva.

Cholangitis

Inflammation of the biliary ducts

Meningoencephalitis

Inflammation of the brain and the meninges

Cholecystitis

Inflammation of the gall bladder

Identify the three developmental stages of Ehrlichia and Anaplasma.

Inside a leukocyte the bacteria grow and reproduce through three developmental stages: an elementary body, an initial body, and a morula. The release of the cells from the morula and into the blood makes them available to feeding ticks.

Variant Creudzfeldt Jacob disease (vCJD)

Is the human form of mad cow disease

How long must an infected tick remain on its host in order to transmit enough spirochetes to establish a borrelia infection?

Laboratory studies have shown that infected ticks must remain on a host for 48 hours in order to transmit enough spirochetes to establish a Borrelia infection in that host.

What side of the heart does sub-Localized to the left side of the heart affect and what does it do?

Localized to the left side of the heart and it attacks deformed valves

What are some of the symptoms of septicemia?

Low BP, vasodialation, ↓body temp, increased HR, increased breathing, increased clotting, anemia, poor perfusion, ↓ blood glucose, ↓ urine out put, multiple organ failure and death

Which type of respiratory infection is more severe, lower or upper?

Lower respiratory

Borrelia causes two diseases in humans what are they?

Lyme disease and relapsing fever

Name another disease caused by Chlamydia trachomatis

Lymphogranuloma venereum. It starts out as an initial genital lesion followed by formation of a buboe. It can cause genital sores, urethral constriction and genital elephantisis.

What is Chlamydia trachoma? when does infection typically occur?

Occular disease and the leading cause of non traumatic blindness in Humans. Infection typically occurs during childbirth

Once the tick bites the human and the bacteria are in the blood what does each bacterium do?

Once in the blood, each bacterium triggers its own phagocytosis by a white blood cell (either a monocyte in Human monocytic Ehrlichiosis (HME) or a neutrophil in anaplasmosis).

What is the treatment of choice for syphilis?

PCN

What can reinfection of Chlamydia trachomatis cause?

PID

Meningoencephalopathy

Primary amoebic diseases called naegleria and acanthoaoemba

What can severe cases of Chlamydia pneumoniae resemble?

Primary atypical pneumonia caused by Mycoplasma pneumoniae

During what phase of syphilis is the fetus most likely to die?

Primary or secondary syphilis

H.Pylori has numerous virulence factors that allow it to survive the acids in the stomach and colonize, what are they? 2- How can H.Pylori be diagnosed?

Proteins that inhibit production of stomach acid, they have flagella that help the bacteria burrow through the stomach lining, adhesins facilitate binding to gastric cells and enzymes help neutralize stomach acid →urea →ammonia 2- By a positive urease test

R. rickettsii is unable to multiply in the external environment. Where does it grow?

R. rickettsii grow and live within the cytosol of host cells

The intracellular form of Chlamydia trachomatis is the _________body.

Reticulate

Transovarian transmission by hard ticks is associated with members of the genus________

Rickettsia

What causes spotted fever rickettsiosis (principally Rocky Mountain spotted fever, RMSF ) The most severe and most reported rickettsial illness.

Rickettsia rickettsii,

Which species of staphylococcus is responsible for over half of the bacterial endocarditis infections?

Streptococcus viridans

Over Half of all SBE are caused by which bacteria?

Streptococcus Viridans

This type of non-venereal syphilis causes Pintas. Describe Pintas

T. carateum causes pinta, a skin disease seen in children in Central and South America. The spirochetes are spread among the children by skin-to-skin contact. After one to three weeks of incubation, hard, pus-filled lesions called papules form at the site of infection; the papules enlarge and persist for months or years, resulting in scarring and disfigurement.

Types of nonveneral treponemal diseases seen in impoverished children living in unsanitry conditons are?

T.pallidum endemicum, T.pallidum pertenue and T.pallidum carateum

The different forms associated with the dimorphic fungi that cause systemic mycoses are influenced by which of the following factors?

Temperature At environmental temperatures (typically below 30°C) these fungi appear as mycelial thalli composed of hyphae. At body temperature (37°C) they grow as spherical yeasts.

What are the more important pathogenic vibrios of humans? Where are pathogenic gram negative Vibrios found?

The more important pathogenic vibrios of humans are in the genera Vibrio, Campylobacter, and Helicobacter - mostly in watery environments world wide

Rabies is a disease of which body system? What family is it in? What are the two kinds of rabies infections called? How are rabies detected? How are rabies treated?

The nervous system -Lyssavirus -Furious rabies and paralytic rabies - By Negri bodies in neural tissue, they stain very dark - First by Human rabies immune globulin followed by a series of vaccines called Huamn rabies diploid cell vaccine (HDCV) 5 intramuscular injections

How many divisions of fungi are there

There are three divisions of fungi: Zygomycota, Ascomycota, and Basidiomycota.

What is the Chlamydia cell wall composed of?

They do not have cell walls, they have two membranes without any peptidoglycan between them.

Why is it unusual that they are obligate intracellular parasites?

They have functional genes for protein synthesis, ATP production and reproduction

What is gram positive septicemia due mostly to?

Toxemia from exotoxin production

What does Gram positive septicemia release into the blood stream?

Toxins

The leading cause of nontraumatic blindness in humans is an eye disease called?

Trachoma

What are the three genera of Spirochetes that cause human diseases?

Treponema, Borrelia and Leptospira

True or False: Xenodiagnosis is sometimes used to demonstrate Trypanosoma cruzi infection.

True: This procedure uses uninfected kissing bugs to feed on a patient suspected of being infected with Trypanosoma cruzi; if the bugs are found to harbor T. cruzi four weeks after feeding on the patient, then a diagnosis of Chagas' disease is made.

Chagas disease

Trypanosoma cruzi- Opossums and armadillos are the primary reservoirs for T. cruzi ,but most mammals, including humans, can harbor the organism.

What does the development cycle of Chlamydia involve?

Two forms: Elementary bodies (EBs) and larger Pleomorphic reticulate bodies (RBs). Both forms can occur within the phagosome of the host cell

Which of the following types of hypersensitivity is most frequently caused by fungal allergens? type I type II type III type IV

Type I Fungal allergens typically trigger type I hypersensitivity resulting from the binding of immunoglobulin E to allergens. This causes common allergic responses such as asthma and eczema.

Occult/Idiopathic septicemia

Unidentifiable cause of sepsis

How do uninfected Nymphs become infected?

Uninfected nymphs can become infected at this time if they feed on an infected host.

Where is the most common pathogenic gram negative Vibrios to infect humans?

Vibrio cholerae- can survive in fresh water and causes the disease known as cholera

How is relapsing fever treated?

With doxycycline or, in pregnant women and children, with erythromycin.

Where does Chlamydia grow and multiply?

Within the vesicles of host cells

Both types of relapsing fever are characterized by recurrent episodes of septicemia and fever separated by symptom-free intervals—a pattern that results from the bodies repeated efforts to remove the spirochetes. How does the body respond to these recurrent episodes?

Within the first week of infection, the spirochetes induce a fever, which is associated with chills, myalgia, and headache. In response to infection, the body produces antibodies that are directed against the spirochetes' surface molecules; once the antibodies have targeted the spirochetes, phagocytes clear most pathogens from the blood, and the body's temperature returns to normal. Some the of Borrelia evade the immune response by changing their antigenic surface molecules; when these spirochetes multiply, they induce a relapse of fever. The body mounts a second immune response, this time against the new antigens, eventually again clearing the blood of most spirochetes and again returning body temperature to normal. But a few spirochetes yet again change their antigenic components, leading to still another recurrence of fever, continuing the pattern.

As an obligate intracellular organism, R. rickettsii must carry out its entire life cycle within a?

a eukaryotic cell.

Describe the disease caused by Treponema pallidum.

a sexually transmitted pathogen and the venereal disease that causes Syphilis. Transmission is almost solely via sexual contact

Rickettsia prowazekii causes?

epidemic typhus, 1 which is also called louse-borne typhus because it is vectored by the human body louse, Pediculis humanus

What is the treatment for Rotavirus?

is self-limiting, and treatment involves supportive care, such as replacement of lost water and electrolytes. Prevention of infection involves good personal hygiene, proper sewage treatment, and vaccination.

Where does Rickettsia prowazekii occur mostly?

in crowed unsanitary conditions

IPV, what is it and what is it called? OPV, what is it and what is it called?

inactivated polio virus and it is called Salk vaccine live, attenuated oral polio vaccine post-polio syndrome

How can a human become infected with C. jejuni?

ingestion of contaminated, raw milk

What is dermatomycoses?

is a skin disease caused by a fungus. Examples of dermatomycoses are tinea and cutaneous candidiasis.

Rotavirus description

is an almost spherical reovirus with prominent glycoprotein spikes. During replication, rotaviruses acquire and then lose an envelope. Even with-out envelopes, they function like enveloped viruses because glycoprotein spikes on their capsids act as attachment molecules that trigger endocytosis, a process common to enveloped viruses. Rotaviruses infect almost all children everywhere in the first few years of life via the fecal-oral route.

What is a whitlow?

is an inflamed blister resulting from infection of HHV-1 and HHV-2 via a cut or break in the skin.

Are there different kinds of treatments for dermatophytes?

no-The treatment recommendations are the same for all dermatophytes

At what pH are echoviruses ineffective?

over a wide range of pH (3-10) and are resistant to alcohol

What are the signs and symptoms of R. Rickettsii?

patients experience fever, headache, chills, muscle pain, nausea, and vomiting. In most cases (90%), a spotted, nonitchy rash develops on the trunk and appendages —including the palms and soles, In about 50% of patients, the rash develops into sub-cutaneous hemorrhages called petechiae In severe cases, the respiratory, central nervous, gastrointestinal, and renal systems fail. Encephalitis may also occur, producing language disorders, delirium, convulsions, coma, and death. Even with treatment, almost 5% of patients die

Empyema

pus in thelungs