title: Geographic variation of Trypanosoma cruzi discrete typing units from Triatoma infestans at different spatial scales.
abstract: We assessed the diversity and distribution of Trypanosoma cruzi discrete typing units (DTU) in Triatoma infestans populations and its association with local vector-borne transmission levels at various geographic scales. At a local scale, we found high predominance (92.4%) of TcVI over TcV in 68 microscope-positive T. infestans collected in rural communities in Santiago del Estero province in northern Argentina. TcV was more often found in communities with higher house infestation prevalence compatible with active vector-borne transmission. Humans and dogs were the main bloodmeal sources of the TcV- and TcVI-infected bugs. At a broader scale, the greatest variation in DTU diversity was found within the Argentine Chaco (227 microscope-positive bugs), mainly related to differences in equitability between TcVI and TcV among study areas. At a country-wide level, a meta-analysis of published data revealed clear geographic variations in the distribution of DTUs across countries. A correspondence analysis showed that DTU distributions in domestic T. infestans were more similar within Argentina (dominated by TcVI) and within Bolivia (where TcI and TcV had similar relative frequencies), whereas large heterogeneity was found within Chile. DTU diversity was lower in the western Argentine Chaco region and Paraguay (D=0.14-0.22) than in the eastern Argentine Chaco, Bolivia and Chile (D=0.20-0.68). Simultaneous DTU identifications of T. cruzi-infected hosts and triatomines across areas differing in epidemiological status are needed to shed new light on the structure and dynamics of parasite transmission cycles.
authors.affiliation: Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina.
authors.forename: María Del Pilar
authors.initials: Mdel P
authors.lastname: Fernández
authors.affiliation: Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina.
authors.forename: María Carla
authors.initials: MC
authors.lastname: Cecere
authors.affiliation: Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina.
authors.forename: Leonardo Alejandro
authors.initials: LA
authors.lastname: Lanati
authors.affiliation: Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben", ANLIS, Buenos Aires, Argentina.
authors.forename: Marta Alicia
authors.initials: MA
authors.lastname: Lauricella
authors.affiliation: Laboratorio de Biología Molecular de la Enfermedad de Chagas, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor Torres" (INGEBI-CONICET), Vuelta de Obligado 2490, Buenos Aires, Argentina.
authors.forename: Alejandro Gabriel
authors.initials: AG
authors.lastname: Schijman
authors.affiliation: Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina.
authors.forename: Ricardo Esteban
authors.initials: RE
authors.lastname: Gürtler
authors.affiliation: Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina. Electronic address: mvcardinal@ege.fcen.uba.ar.
authors.forename: Marta Victoria
authors.initials: MV
authors.lastname: Cardinal
mesh_terms: D000818:Animals; D001118:Argentina / Q000453:epidemiology; D044822:Biodiversity; D001838:Bolivia / Q000453:epidemiology; D014355:Chagas Disease / Q000453:epidemiology* / Q000469:parasitology; D002677:Chile / Q000453:epidemiology; D003430:Cross-Sectional Studies; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology*; D010239:Paraguay / Q000453:epidemiology; D012424:Rural Population; D014224:Triatoma / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000302:isolation & purification*
keywords: Discrete typing units; Diversity; Molecular epidemiology; Triatoma infestans; Trypanosoma cruzi