Prevalence of malaria resistance-associated mutations in Plasmodium falciparum circulating in 2017-2018, Bo, Sierra Leone.

Detection of the NFSND haplotype in 50% of the samples indicated the increasing prevalence of strains with elevated tolerance to artemeter + lumefantrine (AL) threatening the combination currently used to treat uncomplicated malaria in Sierra Leone. The frequency of mutations linked to resistance to antifolates suggests widespread resistance to the drug combination used for intermittent preventive treatment during pregnancy.