Molecular diagnosis of resistance to antimalarial drugs during epidemics and in war zones

University of Maryland, Baltimore, Baltimore, Maryland, United States
The Journal of Infectious Diseases (Impact Factor: 5.78). 09/2004; 190(4):853-5. DOI: 10.1086/422758
Source: PubMed

ABSTRACT Plasmodium falciparum mutations pfcrt K76T and the dhfr/dhps "quintuple mutant" are molecular markers of resistance to chloroquine and sulfadoxine-pyrimethamine, respectively. During an epidemic of P. falciparum malaria in an area of political unrest in northern Mali, where standard efficacy studies have been impossible, we measured the prevalence of these markers in a cross-sectional survey. In 80% of cases of infection, pfcrt K76T was detected, but none of the cases carried the dhfr/dhps quintuple mutant. On the basis of these results, chloroquine was replaced by sulfadoxine-pyrimethamine in control efforts. This example illustrates how molecular markers for drug resistance can provide timely data that inform malaria-control policy during epidemics and other emergency situations.

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