Diarrhea

Epidemiology


Etiology

Watery diarrhea

Viral

Norovirus (Norwalk) virus Rotaviruses Adenovirus Astrovirus
Genome/structure Positive ss RNA, non-enveloped, Star of David ds RNA (11 segments), non-enveloped, Wheel-like ds DNA, non-enveloped, type 40/41, fibers (penton) Positive ss RNA, non-enveloped
High risk Group settings, e.g., cruise ships Infants Infants, older children, adults Infants, elderly, immunocompromised
Seasonality Occurs year round November-April peak Late fall and winter peak Winter peak
Vaccine No Yes
Prevalence in developed countries has decreased dramatically due to vaccination.
No No

Bloody diarrhea

Pathophysiology


Inflammatory

Noninflammatory

Clinical features



Diagnostics


Treatment

Antidiarrheal agents

Warning

Loperamide should be avoided in patients with suspected invasive diarrhea with inflammatory features, as it reduces intestinal motility, which consequently increases the risk of bacterial colonization and invasion.