Increase of Plasmodium falciparum parasites carrying lumefantrine-tolerance molecular markers and lack of South East Asian pfk13 artemisinin-resistance mutations in samples collected from 2013 to 2016 in Côte d'Ivoire

Abstract

Abstract One of the major obstacles to malaria elimination is the decreased susceptibility of Plasmodium falciparum to most antimalarial drugs. This study was focused on the prevalence of molecular markers linked to P. falciparum resistance to antimalarial drugs at different sites in Côte d'Ivoire. Samples were collected from 2013 to 2016 from asymptomatic and symptomatic subjects in Abengourou, Abidjan, Grand Bassam, and San Pedro. A total of 704 participants were enrolled. All samples were analyzed for pfk13 gene, while 344 samples were examined for pfmdr1. Overall, the success rate of molecular tests was 98.8% (340/344), 99.1% (341/344), and 94.3% (664/704) for pfmdr1 N86Y, pfmdr1 Y184F, and pfk13 genes respectively. Molecular analysis revealed twenty (5.9%; 20/340) and 219 (64.2%; 219/341) mutant alleles for pfmdr1 86Y and pfmdr1 184F, respectively. Twenty-nine cases of mutations in pfk13 gene (4.4%; 29/664) with 2.7% (18/664) of non-synonymous mutations was found. None of the mutations previously described in South East Asia (SEA) involved in P. falciparum resistance to artemisinin derivatives were reported in this study. According to year of collection, a decrease of the prevalence of pfk13 mutation (from 3.6–1.8%) and pfmdr1 N86Y mutation (from 8.5–4.5%) was noticed while an increase of mutant allele of pfmdr1 Y184F proportion (from 39.8–66.4%) was found. Comparing to previous studies in the country, an increase in lumefantrine tolerance of P. falciparum strains were noticed. The results of this study demonstrate the importance of establishing a strong system for molecular surveillance of malaria in Côte d’Ivoire.