Viral enterotoxin is detected as a possible mechanism of pathogenesis in :
Adeno virus
Rota virus
Calcivirus
Astrovirus
Mechanism of Rotavirus diarrhea :
a. Rotavirus destroy mature enterocytes of proximal small intestine.

Loss of absorptive villi and proliferation of secretory crypt cells

– Secretory diarrhea

Brush border enzymes are reduced so unmetabolized disaccharides accumulates resulting.

– Osmotic diarrhea
b. NSP4 = enterotoxin which alteres epithelial cell function and permeability causing secretory diarrhea.
c. Virus evoke fluid secretion by the activation of enteric nervous system in intestinal wall.