Current approaches to malaria chemotherapy and prophylaxis.

Malaria continues to be one of the most serious and widespread parasitic diseases, still occurring in over 100 countries despite concentrated efforts to eradicate it from many regions. Sixty-one countries now report their malaria cases to the WHO, and the latest analysis of these figures' shows little improvement in the overall problem during the last 15 years. Some countries, notably India and China, continue to report downward trends, but the problem continues to deteriorate in rural areas where intense economic development is taking place, particularly in Asia and the Americas. In 1984, 5.3 million cases of malaria were reported to the WHO. This is believed to represent but a small fraction of the total number because, for example, 38 of the tropical African countries do not report their malaria cases. Estimates based on the degree of malaria endemicity suggest a total incidence o f around 100 million cases annually. Chloroquine-resistant falciporum malaria has been confirmed in more than 40 countries, often showing cross-resistance to other drugs, and attempts to combat resistance using combination drugs have led to disturbing reports of side-effects as well as multidrug resistance. Vector control is also impaired in many areas due to insecticide resistance. Faced with these problems, we asked Dr Walther Wernsdorfer, head of the WHO Malaria Action Programme, what is the current WHO philosophy of malaria chemotherapy and prophylaxis?