The mortality consequences of the continued use of chloroquine in Africa: experience in Siaya, western Kenya.

In spite of increasing resistance, chloroquine remains the primary drug for treatment of malaria in most sub-Saharan African countries. We evaluated the effect of drug treatment policy on the case-fatality rates of children, adjusting for differing distributions of malaria and severe anemia. In 1991, 63% of children were treated with chloroquine while the remaining 37% were treated with a regimen that would eliminate and clear parasitemia. Case-fatality rates were 13% and 4.1%, respectively; the proportion of deaths attributable to chloroquine treatment was 69%. The trend in case-fatality rates for malaria decreased as an increasing proportion of children received an effective treatment regimen; adjusted malaria case-fatality rates were 5.1%, 3.6%, and 3.3% in 1992, 1993, and 1994, respectively, when 85% of children in 1992 and 97% of children in 1993-1994 received effective therapy. These 4 years of data provide strong evidence that continued use of chloroquine in areas with resistance is contributing to excess Plasmodium falciparum-related deaths.