First report of the East African mutation in an mosquito in Côte d'Ivoire.

. The intensive use of insecticides in public health and agriculture has led to the development of insecticide resistances in malaria vectors across sub-Saharan Africa countries in the last two decades. The target site point mutation which is among the best characterised resistance mechanisms seems to be changing its distribution patterns on the African continent. The 1014F  mutation originally described only in West Africa is spreading to East Africa while the 1014S  mutation originally described in East Africa, is spreading to West and Central Africa. However, the East- mutation has not been reported in Côte d'Ivoire so far. . Immature stages of were collected from breeding sites at the outskirts of Yamoussoukro, Côte d'Ivoire. Emerging 3-5 day old adult female mosquitoes were tested for susceptibility to deltamethrin 0.05%, malathion 5%, bendiocarb 1% and dichlorodiphenyltrichloroethane (DDT) 4% according to WHO standard procedures. A total of 50 specimens were drawn at random for DNA extraction and identification down to the species level. A subsample of 30 mosquitoes was tested for the East-African mutation using a Taqman assay. . The tested mosquito population appeared to be strongly resistant to deltamethrin (1.03% mortality), bendiocarb (38.46% mortality) and DDT (0% mortality) with probable resistance observed for malathion (92.47%). Among the 41 mosquitoes that were successfully characterized, was predominant (68.3%) followed by   (19.5%) and a few hybrids (7.3%). Out of 30 specimens genotyped for East-, a single hybrid mosquito appeared to be heterozygous for the mutation. . The present study revealed the presence of the East- mutation in Côte d'Ivoire for the first time in and highlights the urgent need to start monitoring the allele and genotype frequencies.