Longitudinal studies of infectious diseases and physical growth of children in rural Bangladesh. II. Incidence of diarrhea and association with known pathogens.

Longitudinal studies were done in two villages rural Bangladesh to learn more about the interactions between infectious diseases and the nutritional status of children. Diarrheal diseases, identified by surveillance of 197 children aged 2-60 months, were studied for bacterial, viral and parasitic enteropathogens in 1978-1979. The annual incidence of diarrhea was highest in children aged 2-11 months, and declined progressively with age from seven to four episodes per child per year. An enteropathogen was identified from rectal cultures taken during diarrhea in 51% of episodes and from 6% of monthly cultures taken when diarrhea was not present. Enterotoxigenic Escherichia coli were the pathogens found most frequently, followed by shigellae and rotaviruses. Diarrheal episodes associated with shigellae had the longest duration, while episodes associated with Vibrio cholerae or with rotavirus were more frequently associated with dehydration. E. coli diarrhea had a peak incidence during the hot months, and shigellosis was more frequent during the cool, dry months.