Acute diarrhea among children from high and low socioeconomic communities in Salvador, Brazil

Abstract

Objective: The etiology and epidemiologic characteristics of acute diarrhea among children of high socioeconomic status (HSES) and low socioeconomic status (LSES) in Salvador, Brazil, were compared.

Methods: From February to May 1994, children with (cases) and without (controls) acute diarrhea less than 5 years of age attending a public university pediatric outpatient clinic (LSES children) and two private outpatient clinics (HSES children) were identified, and their demographic, clinical, and epidemiologic characteristics were analyzed. Their stool samples were examined for enteric bacterial pathogens, rotavirus, and parasites. A polymerase chain reaction (PCR)-based method was used to differentiate Escherichia coli strains associated with diarrhea.

Results: During the 4-month study period, 59 LSES case children, 60 LSES control children, 52 HSES case children, and 49 HSES control children were identified. Low socioeconomic status children with diarrhea were two times younger than HSES children (P < 0.001). Sanitary and water supply conditions were significantly different between the two socioeconomic groups. However, within the same group, with the exception of association of fewer water supplies among HSES cases compared to HSES controls (P < 0.05), these variables were not associated with acute diarrhea. Diarrhea was significantly associated with isolation of one or more pathogens in each group. Enteropathogenic E. coli and Shigella spp were the most common pathogens in LSES children, whereas rotavirus was the most common organism associated with diarrhea in HSES children.

Conclusion: The differences in etiology of acute diarrhea among LSES and HSES children indicate that despite living in the same urban environment in northeastern Brazil, they have distinct risk factors and exposures to infectious agents. Diarrheal control strategies need to take these differences into consideration.