title: Wild populations of Triatoma infestans are highly connected to intra-peridomestic conspecific populations in the Bolivian Andes.
abstract: Triatoma infestans, the major vector of Chagas disease south of the Amazon in South America, has a large distribution of wild populations, contrary to what has previously been stated. These populations have been suspected of being the source of reinfestation of human habitats and could impede the full success of vector control campaigns. This study examined gene flow between intra-peridomestic populations and wild populations collected in the surround areas in three Andean localities in Bolivia. The populations were defined according to temporal, ecological, and spatial criteria. After DNA extraction from the legs of each insect, the samples were analyzed using seven microsatellite markers. First, the analysis of molecular variance (AMOVA) detected an absence of differentiation between wild and intra-peridomestic populations, although strong structuring was observed between the populations within each environment. Then for some populations, the Bayesian method of assignment to inferred populations showed very similar assignment patterns of the members of wild or intra-peridomestic populations in each locality. Finally, the detection of the first-generation migrants within the different populations provided evidence of insect displacement from the wild to the intra-peridomestic environment. This result indicates that, after control campaigns in the Andes, controlling this new paradigm of vector transmission risk stemming from the invasion of human habitats by wild populations of T. infestans requires long-term maintenance of public monitoring to keep the risk at a minimal level. Since wild populations of T. infestans have also been detected elsewhere in Argentina, Paraguay, and Chile, there is an urgent need to take these populations into account in future monitoring of Chagas disease transmission.
authors.affiliation: Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France ; Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia.
authors.forename: Simone Frédérique
authors.initials: SF
authors.lastname: Brenière
authors.forename: Renata
authors.initials: R
authors.lastname: Salas
authors.forename: Rosio
authors.initials: R
authors.lastname: Buitrago
authors.forename: Philippe
authors.initials: P
authors.lastname: Brémond
authors.forename: Victor
authors.initials: V
authors.lastname: Sosa
authors.forename: Marie-France
authors.initials: MF
authors.lastname: Bosseno
authors.forename: Etienne
authors.initials: E
authors.lastname: Waleckx
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Depickère
authors.forename: Christian
authors.initials: C
authors.lastname: Barnabé
mesh_terms: D000818:Animals; D001838:Bolivia; D017753:Ecosystem; D005260:Female; D056426:Genetic Loci / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D005843:Geography; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny; D011157:Population Dynamics; D014224:Triatoma / Q000235:genetics*