Parasites and asthma in Tanzanian children

It has been claimed that parasitic infestation suppresses the development of asthma. Eight Tanzanian schoolchildren in whom asthma was confirmed by the demonstration of exercise-induced bronchospasm were found in an ascaris-endemic area of rural Tanzania. Faecal parasites were found equally commonly in the children with asthma and the ninety-seven non-asthmatic controls. The prevalence of asthma (3.3%) in the school under study was comparable with that found in developed countries.