GI viruses Flashcards
What virus family does polio virus belong to?
Picornaviridae
What is the polio virus genome?
RNA
What is the transmission for polio virus?
Fecal-oral
Which polio vaccine does not have a risk for VAPP?
Inactivated
What are features of the live attenuated polio vaccine?
- Trivalent 2. Replicates in GI tract 3. Shed in stool for 6 weeks following inoculation 4. 1/2mil vaccine doses revert to VAPP
How is viral gastroenteritis different from bacterial in terms of setting?
Viral gastroenteritis can occur in both developed and developing countries
How is viral gastroenteritis different from bacterial in terms of vomiting?
Prominent - can be only disttinguishing feature especially in children
How is viral gastroenteritis different from bacterial in terms of diarrhea?
Common - non-bloody in almost all cases
How is viral gastroenteritis different from bacterial in terms of diagnosis?
Often a diagnosis of exclusion
Rotavirus is most severe for what age group?
3-24 months
What is the genome for rotavirus?
dsDNA, segmented
What is the clinical presentation for rotavirus?
- 1-3d incubation 2. Vomiting and diarrhea for 4-7d, occasional cough 3. 33% of patients have fever >102F 4. Typically infects 3-25mo patients 4. Malabsorptive diarrhea
What is the pathogenesis for rotavirus?
1.
What does the rotavirus NSP4 toxin do?
Induces calcium release
Which rotavirus toxin induces calcium release?
NSP4
What is the diagnosis for rotavirus?
- EIA - looking for Abs to virus 2. EM, rtPCR
What are the rotavirus vaccines?
- Rotateq 2. Rotatrix
What does the Rotateq vaccine protect against?
G1-G4, G9
How is the Rotateq vaccine made?
Reassortment between human and bovine rotaviruses
How is the Rotatrix vaccine made?
Live attenuated strain of human rotavirus G8
What age is recommended for the rotavirus vaccine?
Before 12 weeks
What are the clinical symptoms of norovirus?
- Incubation 24-48h 2. Nausea, vomiting, diarrhea for 24-60h 3. 50% have low grade fever 4. Affects all age groups 5. Pathology similar to rotavirus
What virus family does norovirus belong to?
Caliciviridae
What is the norovirus genome?
+ssRNA
What is the transmission for norovirus?
Fecal-oral
What is the virulence for norovirus?
As few as 100 virions can infect
What is the genome for adenovirus?
dsDNA, naked capsid
Which adenovirus serotypes cause GI disease?
40 and 41
What are the clinical manifestations for adenovirus gastroenteritis?
- 8-10d incubation 2. May have fever and vomiting 3. Watery, non-bloody diarrhea 7-8d 4. No seasonal variation 5. Primarily in children
What is the diagnosis for GI adenoviruses?
Looking for antigens to adenovirus in stool sample
What is the astrovirus genome?
+ssRNA
