PATHOGEN-SPECIFIC RISK-FACTORS AND PROTECTIVE FACTORS FOR ACUTE DIARRHEAL DISEASE IN URBAN BRAZILIAN INFANTS

To evaluate potential risk factors and protective factors for acute diarrheal disease in urban infants, 500 infants less-than-or-equal-to 1 2 months old with diarrhea and 500 age-matched control subjects coming to a Sao Paulo emergency room were studied. On multivariate analysis, these apparently sporadic community-acquired cases of diarrhea were significantly associated with hospitalization in the month before onset (odds ratio [OR], 3.4), day care center exposure (OR, 2.0), prior diarrhea in another household member (OR, 4.4), and low family income (OR, 1.8). Breast-feeding infants < 6 months old (OR, 0.3) and boiling household drinking water (OR, 0.4) were protective. Enteropathogenic Escherichia coli (EPEC; OR, 12.0) and Salmonella (OR, 7/0, discordant pairs) infections were associated with prior hospitalization, rotavirus infections were associated with day care (OR, 6/0), and breast-feeding was protective against EPEC infections (OR, 0. 1). These results suggest that certain preventive strategies can prevent a substantial proportion of cases of diarrheal disease in Brazilian infants.