title: Population genetic structure of Anopheles gambiae and Anopheles arabiensis in Niger.
abstract: The increasing usage of long-lasting insecticide-treated nets allows protection of millions of people from malaria infection. Monitoring studies should be planned during any wide-scale malaria control program integrating insecticide-treated materials, to evaluate their effects and effectiveness on epidemiologically relevant parameters. Such operational control interventions may be challenged by insecticide resistance spread within vector populations, as a result of wide insecticide pressure. A nationwide distribution of long-lasting insecticidal nets was implemented throughout Niger in 2005. We studied the population genetic structure of major malaria vectors across Nigerien Sahel, and investigated potential effects of this large malaria control intervention. Wild-caught Anopheles gambiae sensu lato females from seven villages and two wet seasons were genotyped at 12 microsatellite loci. The genetic diversity within both species appeared homogenous between villages and years. The estimated genetic differentiation among samples was very low within both species, indicating high gene flow across the area. An absence of differentiation was also found between 2005 and 2006 wet seasons, for all samples but one, showing that the net distribution did not impact significantly the genetic diversity and structure of vector populations in a single year. We provide valuable results participating to document effects of large malaria control programs, to maximize the efficiency of available tools in future interventions.
authors.affiliation: Centre de Recherche Médicale et Sanitaire, Institut Pasteur International Network, Niamey, Niger. cyril_czeher@yahoo.fr
authors.forename: Cyrille
authors.initials: C
authors.lastname: Czeher
authors.forename: Rabiou
authors.initials: R
authors.lastname: Labbo
authors.forename: Gaelle
authors.initials: G
authors.lastname: Vieville
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Arzika
authors.forename: Hervé
authors.initials: H
authors.lastname: Bogreau
authors.forename: Christophe
authors.initials: C
authors.lastname: Rogier
authors.forename: Laure
authors.initials: L
authors.lastname: Diancourt
authors.forename: Sylvain
authors.initials: S
authors.lastname: Brisse
authors.forename: Frédéric
authors.initials: F
authors.lastname: Ariey
authors.forename: Jean-Bernard
authors.initials: JB
authors.lastname: Duchemin
mesh_terms: D000818:Animals; D000852:Anopheles / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D002675:Child, Preschool; D007446:Chromosome Inversion; D002874:Chromosome Mapping; D002980:Climate; D017753:Ecosystem; D005260:Female; D006580:Genetic Carrier Screening; D014644:Genetic Variation; D005828:Genetics, Population / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007306:Insecticides / Q000494:pharmacology; D008288:Malaria / Q000517:prevention & control / Q000635:transmission; D018895:Microsatellite Repeats / Q000235:genetics; D057147:Mosquito Nets; D009548:Niger; D014960:X Chromosome
chemical_list: D007306:Insecticides