RNA viruses Flashcards
picorno virus family
+ sense RNA, naked, utilization of RNA polymerase,
transmission of picorno?
fecal-oral
members of picorno virus?
hepatitis A, enteroviruses (coxzakie A&B, polioviruses, echoviruses), rhinoviruses
what is the main cause of aseptic meningitits?
enteroviruses
how does CSF look for viral meningitis?
glucose normal, aseptic/without bacteria, protein elevated
is polio acid stable?
YES
where does polio virus replicates? how long?
enter GI, replication in peyer’s patches and tonsils, 2-3 weeks
what is the polio virus target?
anterior horn of spinal cord, LMN
what are the two vaccines of polio?
salk = killed vaccine, sabin = live, attenuated
Which immune responses do the salk and sabin vaccines elicit?
Salk = IgG, Sabin = IgG and IgA
Coxzakie A virus?
hand, food, and mouth disease - red vesicular rash
What microbes cause rashes on the hands and feet?
coxzakie A, syphilis, rickettsia rickettsi
Coxzakie B virus?
dilated cardiomyopathy, devils grip/bornholm’s disease/pleurodynia
what is unique about rhinovirus transmission?
unlike other picoviruses, rhinovirus is acid labile and thus cannot be transmitted through GI tract. instead, respiratory, fomites - attach to ICAM1 of host cells
what are two acid labile bacteria?
salmonella and cholera
where does rhinovirus affect?
upper respiratory, lives in colder temps?
calicivirus
produces one long polyprotein that is cleaved into bits by viral protease
where do all + RNA viruses replicate?
cytoplasm
what is most common clinical cailicirus?
norovirus
who gets norovirus?
day care centers, schools, cruises, shellfish eaters
flavivirus
positive sense enveloped RNA virus
kinds of flavivirus?
dengue/breakbone fever, hep C, yellow fever, west nile virus
dengue fever
thrombocytopenia, renal failure, septic shock
yellow fever
jaundice, backache, blood diarrhea and vomiting
yellow fever symptoms?
encephalitis, meningitis, flaccid paralysis, seizures, coma
hep c transmission?
blood (blood transfusion < 80s, IV drugs, tattoos), prison, placenta, sex, breast feeding
what do LFTs look like in hepatitis infection?
rise and then fall by 6 mo
I say cryoglobulins, you say?
Hep C - serum proteins that contain IgM and can precipitate in cooler temperatures
Hep C tx?
1) Ribavirin and Interferon alpha 2) sofusbivir, protease inhibitor
How does Hep C so beautifully evade our immune system?
lack 3-5 exonuclease activity in RNA polymerase so envelope continually undergoes antigenic variation
how does hep C differ from hep B in regards to length of infection?
Hep C commonly goes onto be chronic, whereas hep B is often acute
arbovirus
arthropods - western, eastern, and venezuelan encephalitis; no treatment
3 types of rubella?
congenital rubella, childhood, adulthood
classic triad of congenital rubella?
congenital cataracts, sensory-neural deafness, patent ductus arteriosus
describe MMR vaccine?
live attenuated, avoid in pregnant and immunocompromised (HIV must have CD4>200)
whats the buzzword for rubella?
unvaccinated/foreigner
general symptoms of rubella?
descending rash starting on face, posterior and occipital lyphadenopathy, fever, arthralgias
list viruses that can cause the common cold
coronavirus, rhinovirus
what acute condition can coronavirus lead to?
acute bronchitis and acute respiratory distress syndrome
what are HIVs main protein??
pol (reverse transcriptome) , gag = p24 (capsule for RNA strands), env = gp41 and 120
function of env?
gp41 = transmembrane protein, gp 120 = surface protein
what two cells does HIV target?
CD4 T cells and macrophages
what differentiates HIV from AIDS?
CD4 count < 200
what are some HIV associated diseases?
diffuse large B cell lymphoma, karposi sarcomi, oral hairy leukoplakia
what surface receptors must HIV bind in order to gain access to cells?
CXCR4, CCR5
how to test for HIV?
Elisa, if + follow with western blot, use PCR to measure viral load
how do you test HIV neonates?
HIV RNA and DNA amplification tests
which receptor is used by HIV to infect cells in early phase?
CCR5
what categories of drugs are used in HIV tx?
NRTIs (integrate and hault elongation), NNRTIs (inhibits RT in other ways), protease inhibitors (cleave proteins vital for RT), Maraviroc (CCR5 inhibitor)
