RESUMEN
In order to relate etiology of diarrhea to the duration of the episode, a cohort of 452 children up to 36 months of age was visited once weekly at their households for 18 consecutive months to record diarrheal morbidity. Fecal specimens were obtained in 453 diarrheal episodes occurring in 354 children during this period. The common putative agents as single isolations associated with diarrhea were EA-AggEC (17.2%), ETEC (14.1%), EPEC (6.0%) and rotavirus (4.0%). The pathogens with higher median duration of diarrhea were Shigella (13.5; mean +/- SD 13.7 +/- 2.7), Salmonella (8.8: 15.3 +/- 4.5) and EA = AggEC (12.0: 15.1 +/- 1.8). Of 55 episodes with duration of greater than 14 days, the main pathogens isolated were EA-AggEC (32.7%), ETEC (9.0), Salmonella, G. lamblia (5.5% each) and Shigella (3.5%). These data provide a preliminary evidence to suggest that EA = AggEC may well be the main long sought microbial agent responsible for diarrhea of long duration.