Seasonal variation of paediatric diseases in The Gambia, west Africa.

In a 3-year prospective study of 9584 consecutive paediatric admissions to the Royal Victoria Hospital in Banjul, The Gambia, we examined the impact of seasonal variations in childhood diseases. The four principal diseases (falciparum malaria, pneumonia, gastro-enteritis and malnutrition) all peaked in September to October following the rainy season. The mortality rate was also higher in the rainy season than in the dry season. Of the 1525 children with cerebral malaria, 83% were admitted during the extended rainy season from July to December. With the emergence of chloroquine-resistant malaria over the 3 years, there was a 27% annual increase in severe anaemia owing to malaria. The median age of malarial anaemia (23 months) was significantly younger than that of cerebral malaria (42 months). Malnutrition peaked immediately following the annual rainy season epidemics of bacterial gastro-enteritis but was not associated with the cool dry season rotavirus outbreaks. Rainy season diarrhoea was also associated with more persistent diarrhoea, an older mean age and a higher mortality. Meningitis was caused by either pneumococcus or Haemophilus influenzae in 64% of cases, of whom 19% were 0-2 months of age. Causes of death in hospital showed good agreement with Gambian community studies. We conclude that analysis of hospital data in a developing country can give accurate information on childhood morbidity and mortality patterns which can be used to set priorities for health care interventions. Seasonal variation is a cardinal feature of paediatric diseases in this part of Africa, and accentuates the vulnerability of children in poor families.