enteric viruses Flashcards
compare rotavirus to influenza virus?
both segmented, dsRNA that have capped mRNA
only influenza undergoes splicing
how can rotavirus be diagnosed?
rapid antigen tests
PCR/immunoassay for serotype (not usually done)
which virus causes cytoplasmic inclusion bodies with virus assembly in cytoplasm?
rotavirus
what are the two pathogenic mechanisms causing diarrhea by rotavirus?
NSP4: enterotoxin-like activity, alters apical membrane permeability increasing Cl secretion
osmotic diarrhea: impaired Na-glucose transport after damaging epithelium
what is the genome for norovirus? how is it diagnosed?
+ssRNA
RT-PCR assay (no rapid tests)
compare immunity in rotavirus and astrovirus to norovirus?
rotavirus/astrovirus: antibodies obtained early in life but wane in later years
norovirus: immunity wanes in about 6 months and antigenic diversity created by antigenic drift
what is the genome of astrovirus?
+ssRNA
who does astrovirus affect?
children
what virus is seen in summer and fall? why?
enteroviruses
replicate best at 37C
what is unique about the course of infection by enteroviruses amongst enteric viruses?
infects lymphoid tissue of URT and gut first before spreading to target organs with viremia
what is unique about the transcription of enteroviruses?
don’t require cap-binding proteins for translation of mRNA’s so continue to make viral proteins when host cell stops translation
who does adenovirus cause diarrhea in?
children
what viruses cause gastroenteritis in young children, show antibodies in most children?
rota, astro, adeno
what is the genotype of adenovirus?
linear dsDNA
what is unique about the course of adenovirus?
relatively long: 1 week incubation, 8-12 day duration
