Seasonal diarrhoeal mortality among Mexican children

The study investigated the effects on diarrhoeal deaths among under-5-year-old Mexican children of the following variables: season (summer or winter), region (north versus south), age group, and place of death. Examination of death certificates indicated that the distribution of deaths in 1989-90 was bimodal, with one peak during the winter and a more pronounced one during the summer. In 1993-94, however, the winter peak was higher than that in the summer (odds ratio (OR) = 2.04). These findings were due mostly to deaths among children aged 1-23 months (OR = 1.86). Diarrhoeal mortality was highest among children aged 6-11 months (OR = 2.23). During the winter, there was a significant increase in the number of deaths that occurred in medical care units and among children who had been seen by a physician before they died, but deaths occurring at home showed no seasonal variation. In the northern states, the reduction in diarrhoeal mortality was less in winter than in summer (OR = 2.62). In the southern states, the proportional reduction during the winter was similar to that in the summer.