title: Molecular epidemiology of Trypanosoma cruzi and Triatoma dimidiata in costal Ecuador.
abstract: Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. In Ecuador, Triatoma dimidiata and Rhodnius ecuadoriensis are the main vector species, responsible for over half of the cases of T. cruzi infection in the country. T. dimidiata is believed to have been introduced in Ecuador during colonial times, and its elimination from the country is thus believed to be feasible. We investigated here the molecular ecology of T. dimidiata and T. cruzi in costal Ecuador to further guide control efforts. Analysis of the Internal Transcribed Spacer 2 (ITS-2) of 23 specimens from Progreso, Guayas, unambiguously supported the likely importation of T. dimidiata from Central America to Ecuador. The observation of a very high parasite infection rate (54%) and frequent feeding on humans (3/5) confirmed a continued risk of transmission to humans. All genotyped parasites corresponded to TcI DTU and Trypanosoma rangeli was not detected in T. dimidiata. TcI subgroups corresponded to TcIa (25%), and mixed infections with TcIa and TcId (75%). Further studies should help clarify T. cruzi genetic structure in the country, and the possible impact of the introduction of T. dimidiata on the circulating parasite strains. The elevated risk posed by this species warrants continuing efforts for its control, but its apparent mobility between peridomestic and domestic habitats may favor reinfestation following insecticide spraying.
authors.affiliation: Centro de Referencia Nacional de Parasitología, Instituto Nacional de Investigación en Salud Pública Leopoldo Izquieta Perez (INSPI), Guayaquil, Ecuador.
authors.forename: Yim Yan
authors.initials: YY
authors.lastname: Wong
authors.affiliation: Centro de Referencia Nacional de Parasitología, Instituto Nacional de Investigación en Salud Pública Leopoldo Izquieta Perez (INSPI), Guayaquil, Ecuador.
authors.forename: Karen Jeniffer
authors.initials: KJ
authors.lastname: Sornosa Macias
authors.affiliation: Centro de Referencia Nacional de Parasitología, Instituto Nacional de Investigación en Salud Pública Leopoldo Izquieta Perez (INSPI), Guayaquil, Ecuador.
authors.forename: Doris
authors.initials: D
authors.lastname: Guale Martínez
authors.affiliation: Centro de Referencia Nacional de Parasitología, Instituto Nacional de Investigación en Salud Pública Leopoldo Izquieta Perez (INSPI), Guayaquil, Ecuador.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Solorzano
authors.affiliation: Laboratorio de Parasitología, Centro de Investigaciones Regionales "Hideyo Noguchi", Universidad Autónoma de Yucatán, Merida, Yucatan, Mexico.
authors.forename: Maria Jesus
authors.initials: MJ
authors.lastname: Ramirez-Sierra
authors.affiliation: Department of Tropical Medicine, Vector-Borne Infection Disease Research Center, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, USA.
authors.forename: Claudia
authors.initials: C
authors.lastname: Herrera
authors.affiliation: Centro de Referencia Nacional de Parasitología, Instituto Nacional de Investigación en Salud Pública Leopoldo Izquieta Perez (INSPI), Guayaquil, Ecuador; Laboratorio de Parasitología, Centro de Investigaciones Regionales "Hideyo Noguchi", Universidad Autónoma de Yucatán, Merida, Yucatan, Mexico; Department of Tropical Medicine, Vector-Borne Infection Disease Research Center, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, USA. Electronic address: edumonte@tulane.edu.
authors.forename: Eric
authors.initials: E
authors.lastname: Dumonteil
mesh_terms: D000818:Animals; D014355:Chagas Disease / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D021901:DNA, Intergenic / Q000235:genetics*; D017753:Ecosystem; D004484:Ecuador / Q000453:epidemiology; D005247:Feeding Behavior / Q000502:physiology; D005260:Female; D005838:Genotype; D006801:Humans; D007300:Insect Control; D007303:Insect Vectors; D058865:Introduced Species; D008018:Life Cycle Stages / Q000235:genetics*; D008297:Male; D017720:Molecular Epidemiology; D010802:Phylogeny; D012239:Rhodnius / Q000469:parasitology; D014224:Triatoma / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000469:parasitology; D014349:Trypanosoma cruzi / Q000472:pathogenicity / Q000502:physiology
chemical_list: D021901:DNA, Intergenic
keywords: Chagas disease; Genotype; Triatoma dimidiata; Triatomine; Vector ecology