Combined chloroquine/Fansidar-resistant falciparum malaria appears in East Africa.

The first two cases from East Africa of RII chloroquine- and Fansidar-resistant falciparum malaria are described. The first case occurred in a non-immune Swedish expatriate 2 weeks after arrival in Tanzania, and the second in a semi-immune Tanzanian soldier. Fansidar has not yet been marketed in Tanzania. The significance and etiology of the occurrence of combined chloroquine/Fansidar resistance in East Africa are discussed.