First report of the East Africankdrmutation in anAnopheles gambiaemosquito in Côte d'Ivoire.
Background. 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. Thekdrtarget site point mutation which is among the best characterised resistance mechanisms seems to be changing its distribution patterns on the African continent. The 1014Fkdrmutation originally described only in West Africa is spreading to East Africa while the 1014Skdrmutation originally described in East Africa, is spreading to West and Central Africa. However, the East-kdrmutation has not been reported in Côte d'Ivoire so far.Methods. Immature stages ofAnopheles gambiae s.l.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 50An. gambiae s.l.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-Africankdrmutation using a Taqman assay.Results. 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,An. coluzziiwas predominant (68.3%) followed byAn. gambiaes.s.(19.5%) and a few hybrids (7.3%). Out of 30 specimens genotyped for East-kdr, a single hybrid mosquito appeared to be heterozygous for the mutation.Conclusion. The present study revealed the presence of the East-kdrmutation in Côte d'Ivoire for the first time inAn. gambiaeand highlights the urgent need to start monitoring the allele and genotype frequencies.
Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Cote d'Ivoire.
Mouhamadou
M
Chouaïbou
Centre Suisse de Recherches Scientifiques en Côte d'Ivoire (CSRS), Abidjan, Cote d'Ivoire.|Université Nangui Abrogoua, Abidjan, Cote d'Ivoire.
Fodjo Behi
FB
Kouadio
Centre d'Entomologie Médicale et Vétérinaire, Université Alassane Ouattara, Abidjan, Cote d'Ivoire.
Emmanuel
E
Tia
Institut Régional de Santé Publique, Ouidah, Benin.|Université d'Abomey-Calavi, Ouidah, Benin.
Luc
L
Djogbenou
Anopheles gambiae; Insecticide resistance; Malaria; Vector control; kdr mutation