Etiology of gastroenteritis among Americans living in the Philippines.

Between December 1975 and June 1976, American military personnel with diarrhea who were seen at an outpatient clinic at Clark Air Force Base Hospital were investigated to determine the etiology of their disease. Enterotoxigenic Escherichia coli were detected in 16% (18/115), rotavirus in 4% (4/111), salmonellae in 3% (3/115), shigellae in 2% (2/115) and Giardia lamblia in 2% (3/152) of patients with diarrhea. Thus from only 27% of the subjects studied were identifiable potential pathogenic agents found. The incidence of gastroenteritis increased in May and June with the increase in rainfall; however, there was no increase in the proportion of diarrhea caused by any of these identifiable enteric pathogens. Americans experienced a seasonal increase of diarrhea similar to that affecting the Philippine population in Manila. Enterotoxigenic E. coli was the most common identifiable enteric pathogen among Americans with diarrhea at Clark Air Force Base in the Philippines during the study, though even in these cases, it may not have been the agent responsible for their illness.