Immunology of Malaria

Abstract

Malaria still ranks as the most serious parasitic disease of the tropical world despite the massive investment in eradication and control measures, these being directed primarily against the vectors. Vast areas have been rendered malaria free and are likely now to remain so. Increasingly, however, there are reports of the resurgence of infection in countries where control programs were in operation, and feasible methods for control for other parts of the world—much of the African continent, for example—have not yet emerged. Figures which illustrate the magnitude of the problem are worth repeating here, as an introduction to the immunology of the disease, because they give us some clues as to the nature of the immune response to the parasite that occurs in man. In Africa alone, there are something like 100 million cases of malaria every year, and about 1 million deaths, mainly in children, directly attributable to the disease. Malaria is also a direct cause of considerable morbidity and has other less obvious effects (WHO, 1974a). Deaths of children from malaria usually occur in those areas where the disease is transmitted regularly—the so-called stable malaria regions. In regions where transmission is irregular—the unstable malaria zones—epidemics may occur and affect a much wider age range. Elsewhere, although less important, cases of “imported” or “introduced” malaria may occur.