Aetiology

More than 90% of infectious diarrhoea in infants has a viral aetiology - in fact 90% is caused by rotavirus, a virus which can cause infections of both the GIT and URT. Other viruses include Echo and Enteroviruses.

A bacterial aetiology is suggested by high pyrexia and bloody diarrhoea. This is principally Enteropathic E. coli, although Shigella, Salmonella and Campylobacter should be borne in mind. World-wide, cholera must be considered, especially currently in South America.

Chronic infections might suggest protozoans, for example Giardia lamblia. This causes three or four episodes of foul smelling diarrhoea a day, and a diagnosis is made on the basis of cysts found in the stool.