Pcr-rflp genotyping of pfcrt and pfmdr1 in plasmodium falciparum isolates from children in Vatomandry, Madagascar

Malaria is a parasitic disease caused by a hematozoan of the genus Early diagnosis followed by effective treatment is one of the keys to control this disease. In Madagascar, after more than 60 years of use for the treatment of uncomplicated malaria, chloroquine (CQ) was abandoned in favor of artesunate + amodiaquine (ASAQ) combination because of high prevalence of CQ treatment failure. Surveillance based on the assessment of therapeutic efficacy and genetic markers of resistance to antimalarials is therefore essential in order to detect the emergence of potentially resistant parasites as early as possible. In this context, our study aimed to genotype the chloroquine resistance transporter gene or and multidrug resistance gene 1 or in isolates collected from children in the district of Vatomandry. A total of 142 isolates collected during active case detection of malaria in children under 15 years old, between February and March of 2016 and 2017 in Vatomandry district, were analyzed. (K76T codon) and (N86Y codon) genotyping was carried out by polymerase chain reaction followed by enzymatic digestion (restriction fragment length polymorphism) or PCR-RFLP. The successful rates of amplification of and genes were low, around 27% and 39% respectively. The prevalence of isolates carrying the mutant K76T codon and the mutant N86Y codon was 2.6% [95% confidence interval (95% CI): 0.1 - 15.0%] and 36% [95% CI: 23.7 - 49.7%] respectively. Despite the limited number of samples analyzed, our study highlighted the circulation of isolates carrying both the mutant K76T and N86Y alleles. Although the prevalence of mutations in and genes that we observed was low, other studies should be carried out in order to follow the evolution of these markers in time and space. The use of more sensitive methods will better characterize strains circulating in Madagascar. Artesunate-amodiaquine is used as a first-line treatment for uncomplicated malaria in the country; it is also crucial to monitor the other codons, i.e. 184 and 1246 of the gene, implicated in the resistance of to amodiaquine in Africa.