title: Distribution and pathogenicity of Trypanosoma cruzi isolated from peridomestic populations of Triatoma infestans and Triatoma guasayana from rural Western Argentina.
abstract: We assessed the distribution of Trypanosoma cruzi infection in peridomestic triatomines collected manually at a district-wide scale in rural villages around Olta, Western Argentina, and typed the isolated strains according to their pathogenicity to laboratory mice. Of 1623 triatomines examined, only 14 (0.9%) were infected with T. cruzi based on microscopical examination of feces. The prevalence of T. cruzi infection was 0.8% in Triatoma infestans, 2.3% in T. guasayana, and nil in T. garciabesi, T. platensis, and T. eratyrusiformis. Local transmission occurred in kitchens, store-rooms and goat corrals or nearby, though at very low levels. T. cruzi was detected by at least one parasitological method in 11 (79%) of 14 microscope-positive bugs. Hemoculture was the most sensitive method (67%) followed by culture of organ homogenates, histopathology or xenodiagnosis of inoculated suckling mice (55-58%), and culture of microscope-positive bug feces (46%). The evidence suggests that most of the isolated T. cruzi strains would be myotropic type III. Our study establishes for the first time that peridomestic, microscope-positive T. guasayana nymphs were actually infected with T. cruzi, and may be implicated as a putative secondary vector of T. cruzi in domestic or peridomestic sites.
authors: Instituto Nacional de Parasitologia Dr. Mario Fatala Chaben-ANLIS Dr. Carlos G. Malbrán, Av. Paseo Colón 568, 1063 Buenos Aires, Argentina. mlauri_2000@yahoo.es
authors: Marta A
authors: MA
authors: Lauricella
authors: Raúl L
authors: RL
authors: Stariolo
authors: Adelina R
authors: AR
authors: Riarte
authors: Elsa L
authors: EL
authors: Segura
authors: Ricardo E
authors: RE
authors: Gürtler
mesh_terms: D000818:Animals; D001118:Argentina; D014355:Chagas Disease / Q000469:parasitology / Q000473:pathology / Q000662:veterinary*; D005243:Feces / Q000469:parasitology; D007303:Insect Vectors / Q000145:classification / Q000469:parasitology*; D051379:Mice; D012424:Rural Population; D014224:Triatoma / Q000145:classification / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000302:isolation & purification*