Old Questions Flashcards
how do naked viruses enter host cells?
endocytosis
which of the following viral nucleic acids could be translated without further nucleic acid synthesis?
positive sense RNA
Type of antigens in the MMR vaccine
live attenuated viruses
Family name that includes Hanta virus:
bunyaviridae
For enveloped viruses, where does the envelope come from?
it is derived from the host cell membrane as the virus leaves the cell
The type of antigen in the injected polio vaccine:
inactivated whole viruses
___ indicates rabies infection
negri bodies
Which of the following is the typical host for measles?
humans
Virus that leads to hand, food, and mouth disease=
cocksackievirus
What flavivirus is NOT transmitted by a mosquito?
hepatitis c
most common outcome of polio virus infection:
viral replication in the GI tract that is asymptomatic
Role of ICAM in rhinovirus infections:
viral factor that binds to the host cell receptor
human disease caused by coxsackievirus A16:
hand, foot and mouth disease
Which of the following vaccines will protect against GI replication of poliovirus and paralytic disease?
sabin
most common seasons for enterovirus infections:
summer and fall
What is the virus source of cases of VAPP?
the oral polio vaccine
T/F: all common colds are caused by rhinoviruses
false
T/F: most of the symptoms of enterovirus infections are restricted to the GI tract
False
causeative agent of Hansens disease:
Mycobacterium leprae
lesion that contains live, dormant, tubercule bacteria, surrounded by immune cells is called a:
granuloma
time required for positive culture for Mycobacterium tuberculosis on solid agar plates:
6-8 weeks
region of the US with the highest rates of lyme disease
northeast
primary means of transmission of leptospira to people=
contaminated water inoculated into breaks in the mucosa
joint pain due to lyme disease occurs when?
months to years after initial infection
stage of pregnancy when syphilis has the greatest potential to cause harm to the baby
early in the pregnancy (8-15 weeks)
chief symptom of primary syphilis:
painless chancre
chief symptom of secondary syphilis
rash (runny nose, sore throat, aches)
chief symptom of tertiary syphilis
gummas (CNS and cardiovascular signs)
T/F: antimicrobial resistances are very common for treponema pallidum
false
salpingitis means an infection of:
one or both of the fallopian tubes
causative agent of trachoma
chlamydia trachomatis
causative agent of lymphogranuloma venereum (LGV)=
chlamydia trachomatis
causative agent of epidemic typhus=
rickettsia prowazekii
chlamydia pneumoniae causes:
mild pneumonia
causative agent of Q fever=
coxiella burnetii
T/F: chlamydial cervicitis can be asymptomatic yet still transmissible
true
commonly prescribed antimicrobial for the treatment of chlamydial infections:
tetracyclines (doxycycline)
anatomical site of trachoma:
eye
which of the following is the cause of a pneumonia following a cold?
secondary infections (bacterial or viral)
when associated with serious illness, West Nile virus causes:
encephalitis
which vaccine for polio is currently used in the US?
inactivated polio vaccine (IPV)
what population is most at risk with respect to mortality from west nile infections?
those >50 years old
when a person acquires a west nile virus infection, which of the following is most likely to happen?
no symptoms
Advantage of sabin polio vaccine:
produces intestinal immunity (which reduces infections and therefore reduce the incidence of paralytic disease)
This is the active, attenuated vaccine; contains all 3 serotypes of virus. administered as an oral vaccine;
Best prevention for infections with west nile virus=
avoid mosquitos
When would longer therapy or IV administration be necessary for patients with lyme disease?
late stages of the disease with neurological involvement or myocarditis
causative agent of human monocytic ehrlichiosis=
erhlichia chaffeensis
rickettsia typhi causes:
endemic typhus
much of the damage to the host during infection with chlamydia is due to:
the host immune response
a unique feature of the mycobacterial cell wall is that it:
contains mycolic acid
what makes mycobacterium “acid fast”?
mycolic acid in its cell wall
why is the nymph tick the usual tick form to transmit lyme disease to humans?
b/c it can stay attached to the body long enough to transmit the bacteria without being seen. the larger adult tick is usually discovered before the tick has fed long enough to transmit the bacteria
structurally, spirochetes are:
gram negative
LGV is a form of chlamydia that:
is more invasive and tends to involve the lymph nodes; treatable with antibiotics (longer treatments)
The BCG vaccine tends to work better in:
children than in adults
T/F: someone who has received the BCG vaccine will test positive for TB with the PPD test
true
The lesions associated with primary syphilis are known as:
syphilitic chancres
___ are soft tissue masses associated with tertiary syphilis
gummas
Where are gummas found?
can be found in almost any organ or tissue
typical transmission route for rocky mountain spotted fever=
bite of an infected dog tick
What is the feeding time for a tick to transmit R.rickettsii?
(rocky mountain spotted fever)
6-24 hours
how is epidemic typhus spread?
among people with body lice
Why is a rash seen in patients with rocky mountain spotted fever?
R. rickettsii are obligate intracellular parasites that live inside the endothelial cells lining the blood vessels. The rash is caused by damage to these blood vessels when the bacteria are growing
smallest prokaryotes capable of growth on cell-free media=
mycoplasma
What is a common cause of salpingitis?
chlamydial infections
what happens to the bacteria during stage 2 lyme disease?
the bacteria enter the blood and travel throughout the body which results in variable symptoms
Where do spirochetes replicate with regards to syphilis?
at the site of inoculation of the spirochetes
what is the main symptoms associated with secondary syphilis?
systemic rash that usually begins on palms of hands and soles of the feet
Erythema migrans is often described as a:
bulls eye rash
What strains of C.trachomatis are associated with chlamydia?
D-K
What strains of lymphogranuloma venereum are associated with chlamydia?
L1-L3
Why is treating syphilis so important?
Early treatment prior to tertiary syphilis can prevent irreversible damage to organ systems
How does leptospirosis get into bodies of water?
infected animals shed the bacteria in the urine which will contaminate bodies of water. the bacteria can then gain access to the tissue via small breaks in the skin when the person is swiming
What does RPR stand for?
rapid plasma reagin test
What does VDRL stand for?
venereal disease reference laboratory test
How do you diagnose syphilis?
- nontreponemal tests (RPR or VDRL). If results are + then..
- treponeme-specific test must be administered
How long does a tick need to feed to transmit the bacteria that causes lyme disease?
more than 2 days
What is the typical route for acquiring psittacosis?
birds have the bacteria which is present in their feces and then on their feathers. Humans then inhale the fecal dust which contains the bacteria
testing the STD form of chlamydia currently involves:
growth of the organisms on blood agar plates
Where do rhinoviruses like to live/grow/be?
cooler temperatures in upper respiratory tract
although most common colds are due to rhinoviruses, about 30% are due to:
coronaviruses
Poliovirus is in the ___ family
picornaviridae
Hepatitis A is in the ___ family
picornaviridae
Rhinovirus is in the ___ family
picornaviridae
Coxsackievirus is in the __ family
picornaviridae
Advantage of the sabin polio vaccine=
produces intestinal immunity (this is the live attenuated vaccine)