Mapping partner drug resistance to guide antimalarial combination therapy policies in sub-Saharan Africa

Significance Antimalarial resistance has emerged and spread with every antimalarial deployed to date. Currently, parasite genotypes associated with reduced artemisinin and partner drug sensitivity have been reported in Asia, South America, and, most recently, Africa. Analyzing spatial-temporal trends in molecular markers can help policymakers choose efficacious partner drugs and slow the emergence of artemisinin resistance and spread of multidrug-resistant parasites. We display evidence of a continent-wide increase in molecular markers associated with reduced lumefantrine susceptibility, the partner drug of the most widely used artemisinin-based combination therapy in sub-Saharan Africa. We also generate hypotheses for large-scale demographic and environmental risk factors implicated in the spread of antimalarial resistance. Our results can help identify regions of developing parasite resistance that may require enhanced surveillance.