Hosts and vectors of Trypanosoma cruzi discrete typing units in the Chagas disease endemic region of the Paraguayan Chaco.
Active Trypanosoma cruzi transmission persists in the Gran Chaco region, which is considered hyperendemic for Chagas disease. Understanding domestic and sylvatic transmission cycles and therefore the relationship between vectors and mammalian hosts is crucial to designing and implementing improved effective control strategies. Here we describe the species of triatomine vectors and the sylvatic mammal reservoirs of T. cruzi, in different localities of the Paraguayan and Bolivian Chaco. We identify the T. cruzi genotypes discrete typing units (DTUs) and provide a map of their geographical distribution. A total of 1044 triatomines and 138 sylvatic mammals were captured. Five per cent of the triatomines were microscopically positive for T. cruzi (55 Triatoma infestans from Paraguay and one sylvatic Triatoma guasayana from Bolivia) and 17 animals (12·3%) comprising eight of 28 (28·5%) Dasypus novemcinctus, four of 27 (14·8%) Euphractus sexcinctus, three of 64 (4·7%) Chaetophractus spp. and two of 14 (14·3%) Didelphis albiventris. The most common DTU infecting domestic triatomine bugs was TcV (64%), followed by TcVI (28%), TcII (6·5%) and TcIII (1·5%). TcIII was overwhelmingly associated with armadillo species. We confirm the primary role of T. infestans in domestic transmission, armadillo species as the principal sylvatic hosts of TcIII, and consider the potential risk of TcIII as an agent of Chagas disease in the Chaco.
Departamento de Medicina Tropical,Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asunción - UNA,San Lorenzo CP 2160,Paraguay.
Nidia
N
Acosta
Departamento de Medicina Tropical,Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asunción - UNA,San Lorenzo CP 2160,Paraguay.
Elsa
E
López
Department of Pathogen Molecular Biology,London School of Hygiene and Tropical Medicine,Keppel Street, London WC1E 7HT,UK.
Michael D
MD
Lewis
Department of Pathogen Molecular Biology,London School of Hygiene and Tropical Medicine,Keppel Street, London WC1E 7HT,UK.
Martin S
MS
Llewellyn
Centro para el Desarrollo de la Investigación Científica (CEDIC)/Díaz Gill Medicina Laboratorial/Fundación Moisés Bertoni,Asunción,Paraguay.
Ana
A
Gómez
Centro para el Desarrollo de la Investigación Científica (CEDIC)/Díaz Gill Medicina Laboratorial/Fundación Moisés Bertoni,Asunción,Paraguay.
Fabiola
F
Román
Department of Pathogen Molecular Biology,London School of Hygiene and Tropical Medicine,Keppel Street, London WC1E 7HT,UK.
Michael A
MA
Miles
Department of Pathogen Molecular Biology,London School of Hygiene and Tropical Medicine,Keppel Street, London WC1E 7HT,UK.
Matthew
M
Yeo
D000818:Animals; D001135:Armadillos; D058448:Biota; D014355:Chagas Disease / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D048293:Didelphis; D005260:Female; D005838:Genotype; D008297:Male; D010239:Paraguay / Q000453:epidemiology; D014225:Triatominae / Q000145:classification / Q000469:parasitology* / Q000502:physiology*; D014349:Trypanosoma cruzi / Q000235:genetics / Q000502:physiology*

               Trypanosoma cruzi
            ; Paraguayan Chaco; armadillos; discrete typing units; triatomine vectors