Cryptosporidium infection in Gambian children less than 5 years of age.

Cryptosporidium infection was studied in Gambian children less than 5 years of age over a 12-month period. Children who presented with diarrhoea at the Medical Research Council (MRC) clinic were selected randomly for detection of Cryptosporidium. They were compared with control children who presented with reasons other than diarrhoea. Cross-sectional surveys were conducted also to assess the community prevalence of Cryptosporidium. Cryptosporidium was found in 53 (9%) of 600 children with diarrhoea. In contrast Cryptosporidium was found in only 17 (3%) of 600 control children (chi 2 = 18.6, 1 df, P < 0.001). All 53 children with Cryptosporidium and diarrhoea were less than 2 years of age. In the community surveys, 11 (4%) of 250 children were Cryptosporidium positive. Cryptosporidium infection showed a well defined seasonal peak in association with the rains and a high relative humidity.