Practical chemotherapy of malaria / Practical chemotherapy of malaria

The development of common guidelines on the use of antimalarial drugs is made particularly difficult by the rapidly changing epidemiological patterns of malaria, and their variability even within a country. Recognizing this, the WHO Scientific Group on the Chemotherapy of Malaria, in the present report has attempted no only to make recommendations for the use of specific drugs, but also to provide the technical information needed to evaluate and, if necessary, adapt those recommendations. The report therefore discusses the factors that need to be considered in developing and implementing a policy on the use of drugs in malaria. The management and treatment of both severe and uncomplicated malaria are dealt with in detail, and more general topics, such as estimating the amounts of drugs needed, their procurement, and monitoring systems, are also considered. A separate section deals with antimalarial drugs currently under development. The report is addressed primarily to middle-level planner and administrators responsible for malaria services, but research workers, clinicians and primary health planners wil also find a useful guide to the factor that

In vitro drug sensitivity of Plasmodium falciparum in Acre, Brazil

In Acre, the westernmost state of Brazil in the Amazon ragion, the sensitivity of Plasmodium falciparum to chloroquine, amodiaquine, mefloquine, quinine and uslfadozine/pyrimethamine was determined in vitro by the Rieckmann microtechnique. The study was performed between January and June 1987; the in vitro parasite responses to all antimalarial drugs were determined according to the recommendations of WHO. Of 83 isolates of P. falciparum, all were sensitive to mefloquine and of 87 isolated of P. falciparum, 84 (97 per cent) were sensitive to quinine. The EC50 for mefloquine was 0.27 umol/1 and for quinine 4.60 umol/1. In contrast, 65 of 89 (73 per cent) and 70 of 83 (84 per cent) isolates were resistant to amodiaquine was 0.34 umol/1 and for chloroquine 0.73 umol/1. Sulfadoxine /pyrimethamine resistance was seen in 23 of 25 (92 per cent) cases

These data clearly indicate that in the western part of the Amazon region the 4-aminoquinolines, as well as sulfadoxine/pyrimethamine, can no longer be recommended for the treatment of P. falciparum infections(AU)

A quantitative approach to recommendations on malaria prophylaxis

In order to develop recommendations for malaria prophylaxis, a quantitative method is needed to balance the risk of Plasmodium falciparum malaria infections against the toxicity of antimalarial drugs. Using decision analysis, we estimated the expetect mortality associated with three alternative regimens of prophylactic drugs for visitors to three areas with different risks of infection with chloroquine-resistant P. falciparum. The model used took into account the risks of malaria and of adverse reactions to antimalarial drugs. Estimates of the parameters used in the analysis were base on observations made on U.S. travellers. Reducing the risk of malaria infection was found to have a far greater impact on lowering the expected mortality than that of increasing the chemoprophylactic efficacy of the drugs used, thereby emphasizing the need for travellers to use anti-mosquito measures in malarious areas. The analytical method described can be used to define optimal malaria prevention strategies