The invaders: Phylogeography of dengue and chikungunya viruses Aedes vectors, on the South West islands of the Indian Ocean
Autor(es): Delatte H, Bagny L, Brengue C, Bouetard A, Paupy C, Fontenille D
Resumo: Aedes albopictus - Aedes aegypti are the two main worldwide arbovirus vectors that have experienced invasion phases. Aedes aegypti is a pantropical species that spread centuries ago whereas Ae. albopictus started the main wave of invasion in the 1980s. Both species have been at various times on the different isl-s in Southwestern Indian Ocean (SWIO). This area provides an opportunity to examine the extent to which mosquitoes colonization patterns are influenced by different introductory events likely linked with human settlement - migration between the isl-s. To explore this hypothesis, we propose a CO1-based phylogeny using a large sampling of fresh Ae. albopictus, Ae. aegypti, - Ae. mascarensis, - 50-year-old dry specimens originating from different Indian Ocean isl-s. Our data allow us to hypothesize the existence of at least two waves of invasion for Ae. albopictus in the isl-s of SWIO. The first one most likely occurred several centuries ago with establishments in Madagascar, Mauritius - Reunion Isl-. The other one that appears to currently still on-going, reached almost all the isl-s of SWIO during the 1990s or later. The low genetic diversity found between the ancient invasive strain - the contemporary one, indicates with great certainty that Ae. albopictus is not indigenous to the isl-s of SWIO. Recently, in Madagascar, an invasive lineage of Ae. albopictus has exp-ed all over the isl- while Ae. aegypti populations have declined in urban areas. Three clusters of Aedes aegypti have been observed, two fitting with the wild form Ae. aegypti formosus - the other one fitting with the more domestic form Ae. ae. aegypti. Sequence of Ae. mascarensis, endemic to Mauritius suggest that this species might belong to Ae. aegypti species - on this basis we propose to classify it as a sub species or form of Ae. aegypti species. Given the increase of human population flux on these isl-s, the occurrence of these vectors - their ability to spread quickly are of high importance of arbovirus transmission - the epidemicity of the associated diseases in these isl-s.
Palavras-Chave: mtCOI markers; Invasion; Chikungunya; Dengue; Aedes; Mosquitoes
Imprenta: Infection, Genetics and Evolution, v. 11, n. 7, p. 1769-1781, 2011
Identificador do objeto digital: 10.1016/j.meegid.2011.07.016
Descritores: Chikungunya virus - Arbovirus ; Chikungunya virus - DNA ; Chikungunya virus - Flaviviridae ; Chikungunya virus - Genome ; Chikungunya virus - Molecular structure ; Chikungunya virus - Pathogenesis ; Chikungunya virus - Viral infections ; Chikungunya Virus - Virus ; Chikungunya virus - Transmission ; Chikungunya virus - Dengue ; Chikungunya virus - Epidemiology ; Chikungunya virus - Public health
Data de publicação: 2011
