Wk 3 - Infection: Viral Gastroenteritis Flashcards
List the main viruses associated with human gastroenteritis.
- Rotaviruses
- Adenoviruses 40/41
- Astroviruses
- Sapoviruses
- Noroviruses
How does rotavirus spread?
Faecal-oral spread
What is the incubation period of rotavirus?
24-48 hrs incubation period followed by abrupt onset of vomiting and diarrhoea (± low-grade fever)
Describe the pathogenesis of rotavirus.
- RV infect apical cells of small intestinal villi causing cell death and desquamation
- Necrosis of apical villi reduces digestion, causing diarrhoea through primary malabsorption (leads to villous atrophy
- Villous atrophy compensated by reactive crypt cell hyperplasia giving increased secretin leading to diarrhoea
Why was the 1st rotavirus vaccine suspended?
Due to infants developing intussusception (a serious condition in which part of the intestine slides into an adjacent part of the intestine. This telescoping action often blocks food or fluid from passing through. Intussusception also cuts off the blood supply to the part of the intestine that’s affected)
What are the two types of adenoviruses most associated with viral gastroenteritis?
Types 40 and 41
Unlike rotaviruses, adenoviruses have…
Double-stranded DNA
Astroviruses named so because of…
their star-shaped morphology on electron microscopy
What is the characteristic surface morphology of sapoviruses?
Consist of hollows with the star of David structure particles on 3-fold symmetry
Unlike other viruses, noroviruses affect (which age groups?)…
all age groups vs others mainly neonates and under 3s
What part of the intestine do noroviruses affect?
Noroviruses infect mature enterocytes at the tips of the villi in the small intestine
Norovirus immunity ______ (does/does not) last.
Norovirus immunity does not last.
