title: [The Anopheles gambiae species complex and Kdr resistance gene at the periphery of Douala, Cameroon].
abstract: This study was conducted from May to June 2015 in Yassa (industrialized area) and Logbessou (non-industrialized area), two peri-urban areas of the city of Douala, Cameroon with the aim of an assessment of the spatial distribution of the gambiae complex, the determination of their resistance to insecticides and the distribution of the Kdr mutation. Mosquito larvae were collected by the dipping method and nursed to adult stage. The sensitivity of adult Anopheles gambiae s.l. populations to DDT and pyrethroids was assessed following WHO protocol. All tested mosquitoes were identified by PCR SINE. Only survivors were used to search for the Kdr mutation. In both areas, the gambiae complex included An. coluzzii and An. gambiae sympatric in their breeding sites. However, An. gambiae was predominant in Logbessou (88%) and An. coluzzii in Yassa (68%). Tests with deltamethrin, permethrin and DDT revealed mortality rates below 90% regardless of the area of origin of the mosquitoes. PCR diagnosis of Kdr mutation showed that over 95% of survivors harbored the Kdr gene in both sites, with resistant allele frequencies ranging from 0.96 to 1.0 in An. gambiae and from 0.89 to 0.96 in An. coluzzii. The strong resistance of An. coluzzii and This study was conducted from May to June 2015 in Yassa (industrialized area) and Logbessou (nonindustrialized area), two peri-urban areas of the city of Douala, Cameroon with the aim of an assessment of the spatial distribution of the gambiae complex, the determination of their resistance to insecticides and the distribution of the Kdr mutation. Mosquito larvae were collected by the dipping method and nursed to adult stage. The sensitivity of adult Anopheles gambiae s.l. populations to DDT and pyrethroids was assessed following WHO protocol. All tested mosquitoes were identified by PCR SINE. Only survivors were used to search for the Kdr mutation. In both areas, the gambiae complex included An. coluzzii and An. gambiae sympatric in their breeding sites. However, An. gambiae was predominant in Logbessou (88%) and An. coluzzii in Yassa (68%). Tests with deltamethrin, permethrin and DDT revealed mortality rates below 90% regardless of the area of origin of the mosquitoes. PCR diagnosis of Kdr mutation showed that over 95% of survivors harbored the Kdr gene in both sites, with resistant allele frequencies ranging from 0.96 to 1.0 in An. gambiae and from 0.89 to 0.96 in An. coluzzii. The strong resistance of An. coluzzii and This study was conducted from May to June 2015 in Yassa (industrialized area) and Logbessou (nonindustrialized area), two peri-urban areas of the city of Douala, Cameroon with the aim of an assessment of the spatial distribution of the gambiae complex, the determination of their resistance to insecticides and the distribution of the Kdr mutation. Mosquito larvae were collected by the dipping method and nursed to adult stage. The sensitivity of adult Anopheles gambiae s.l. populations to DDT and pyrethroids was assessed following WHO protocol. All tested mosquitoes were identified by PCR SINE. Only survivors were used to search for the Kdr mutation. In both areas, the gambiae complex included An. coluzzii and An. gambiae sympatric in their breeding sites. However, An. gambiae was predominant in Logbessou (88%) and An. coluzzii in Yassa (68%). Tests with deltamethrin, permethrin and DDT revealed mortality rates below 90% regardless of the area of origin of the mosquitoes. PCR diagnosis of Kdr mutation showed that over 95% of survivors harbored the Kdr gene in both sites, with resistant allele frequencies ranging from 0.96 to 1.0 in An. gambiae and from 0.89 to 0.96 in An. coluzzii. The strong resistance of An. coluzzii and An. gambiae to insecticides highlights the need for developing new mosquito insecticides.
authors.affiliation: Laboratoire de biologie et physiologie animale, Département de biologie animale, Faculté des sciences, Université de Douala, BP. 24 157, Douala, Cameroun. patakono2000@yahoo.fr.
authors.forename: P
authors.initials: P
authors.lastname: Ntonga Akono
authors.affiliation: Laboratoire d'écologie et de parasitologie, Département de biologie et physiologie animale, Faculté des sciences, Université de Yaounde I, BP. 812, Yaoundé, Cameroun.
authors.forename: A
authors.initials: A
authors.lastname: Mbouangoro
authors.affiliation: Laboratoire de biologie et physiologie animale, Département de biologie animale, Faculté des sciences, Université de Douala, BP. 24 157, Douala, Cameroun.
authors.forename: A
authors.initials: A
authors.lastname: Mbida Mbida
authors.affiliation: Organisation de coordination pour la lutte contre les endémies en Afrique Centrale, BP 15665, Yaoundé, Cameroun.
authors.forename: C
authors.initials: C
authors.lastname: Ndo
authors.affiliation: Laboratoire d'écologie et de parasitologie, Département de biologie et physiologie animale, Faculté des sciences, Université de Yaounde I, BP. 812, Yaoundé, Cameroun.
authors.forename: M F
authors.initials: MF
authors.lastname: Peka Nsangou
authors.affiliation: Laboratoire de zoologie, Département de biologie et physiologie animale, Faculté des sciences, Université de Yaoundé I, BP. 812, Yaoundé, Cameroun.
authors.forename: S
authors.initials: S
authors.lastname: Kekeunou
mesh_terms: D000818:Animals; D000852:Anopheles / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D002163:Cameroon; D003634:DDT / Q000494:pharmacology; D005787:Gene Frequency; D017344:Genes, Insect; D005838:Genotype; D006801:Humans; D007305:Insecticide Resistance / Q000235:genetics*; D007306:Insecticides / Q000494:pharmacology; D009154:Mutation; D026023:Permethrin / Q000494:pharmacology; D011722:Pyrethrins / Q000494:pharmacology
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D026023:Permethrin; D003634:DDT
keywords: An. gambiae; Anopheles coluzzii; Douala; Insecticides; Kdr mutation; Kisumu; Logbessou; Sub-Saharan Africa; Yassa