Excess mortality by diarrhea simultaneous to a cholera epidemic in Northeastern Brazil

Abstract

OBJECTIVE: To evaluate excess mortality due to infectious diarrhea without etiological diagnosis, occurring simultaneously to Vibrio cholerae circulation. METHODS: Statistical modeling was applied to a time series of deaths ascribed to "poorly defined intestinal infections" (International Classification of Diseases - ICD-9) and "presumably infectious diarrhea and gastroenteritis" (ICD-10), between 1980 and 1998 in the Northeast Region of Brazil. The prediction of expected values was obtained after a discontinuity point. Excess mortality was calculated as the difference between observed figures and those estimated by the model. RESULTS: Between 1992 and 1994, only 19.3% of deaths by cholera were actually notified. In 1993, the year in which the epidemic reached its peak in the area, our modeling estimated underregistration at 82.2%. CONCLUSIONS: Results indicate substantial underregistration of cholera mortality during the epidemic in Northeastern Brazil.