Exploring the impact of metabolic-based insecticide resistance on the clonal diversity of Plasmodium falciparum in Anopheles funestus

Background The rapid spread of insecticide resistance in malaria vectors raises concerns about its potential impact on disease transmission. This study investigated the influence of two key metabolic resistance markers (GSTe2 and CYP9K1) on the clonal diversity of Plasmodium falciparum in Anopheles funestus population from southern Cameroon. Methods A total of 138 P. falciparum isolates infecting a natural population of An. funestus sampled in Emana-Benyada, Nkol-Feb and Ezenglassi, three localities of southern Cameroon, were genotyped at block 2 of msp1 and block 3 of msp2 to assess parasite polymorphism. The genetic diversity was then compared according to host insecticide resistance genotypes. Results The overall clonal richness was highest in GSTe2 homozygote susceptible mosquitoes with 65 clones followed by RS (N = 53) and RR (N = 52) genotypes. In contrast, for CYP9K1 maker, RR showed the highest number of clones (N = 70), compared with 66 in SS and 52 in RS. Clones common to all genotypes were significantly more frequent (p < 0.0001), representing 71.78% to 90.36% of the entire population of P. falciparum . The heterozygosity was high across markers, ranging from 0.896 to 0.947 in RR, 0.824 to 0.944 in RS and 0.91 to 0.970 in SS. Conclusion Our study indicates that metabolic-based markers influence P. falciparum clonal richness in An. funestus , but do not substantially affect the overall likelihood of multiclonal infection. This study provides novel insight into how vector resistance mechanisms may shape parasite population structure.