title: Triatoma infestans chooses to feed upon immune prey.
abstract: Blood-feeding Triatoma infestans obtained its fills from immune chickens in 15 min, but it needed 40 min for feeding upon non-immune chickens. High-titer specific IgGs and skin reactivity against T. infestans saliva antigens were elicited in immune chickens. Fluorescence-labeled leukocytes from non-immune or immune chickens were used to determine sources of blood drawn by equal numbers of triatomines distributed in separate compartments of a hut-like box. It was shown that 64.4 +/- 4.7% of the reduviids were captured in the immune chicken room; 35.6 +/- 4.5% were present in the non-immune chicken dwelling, and these differences were statistically significant (P < 0.001). Furthermore, T. infestans feeding upon immune birds reached the adult stage 40 days before those feeding upon non-immune birds, and differences were statistically significant. These results appear to have a broad epidemiologic significance as for spreading enzootics; hence, the immunologic status of vertebrate host populations appears to favor T. infestans as the main transmitter of Trypanosoma cruzi.
authors.affiliation: Chagas Disease Multidisciplinary Research Laboratory, Faculty of Medicine, University of Brasília, Federal District, Brazil.
authors.forename: Mariana M
authors.initials: MM
authors.lastname: Hecht
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Bussacos
authors.forename: Silene P
authors.initials: SP
authors.lastname: Lozzi
authors.forename: Jaime M
authors.initials: JM
authors.lastname: Santana
authors.forename: Antonio R L
authors.initials: AR
authors.lastname: Teixeira
mesh_terms: D000818:Animals; D002645:Chickens / Q000276:immunology; D004198:Disease Susceptibility; D005247:Feeding Behavior / Q000502:physiology*; D007303:Insect Vectors / Q000469:parasitology*; D014224:Triatoma / Q000469:parasitology* / Q000502:physiology*; D014349:Trypanosoma cruzi / Q000472:pathogenicity*