Differential pattern of infection of sylvatic nymphs and domiciliary adults of Triatoma infestans with Trypanosoma cruzi genotypes in Chile.
In Chile, the main vector of Chagas disease, Triatoma infestans, is under control after insecticide spraying. However, it has been found colonizing wild habitats. This study evaluated Trypanosoma cruzi infection of sylvatic and domiciliary T. infestans and identified their parasite genotypes. The sample studied was composed mainly of T. infestans sylvatic nymphs and domiciliary adults from a semi-urban area with human dwellings under vector control surveillance. Results showed prevalences of 57.7% in nymphs and 68.6% in adults. Hybridization tests showed a major T. cruzi lineage (TcI) circulating in sylvatic (93.3%) and domiciliary (100%) T. infestans. TcII, TcV, and TcVI were also detected, mainly in nymphs, suggesting differential adaptation of T. cruzi lineages among instars. We also discuss the origin of domiciliary individuals of T. infestans and the risk of human infection by triatomines of sylvatic foci that invade houses despite vector control programs.
Departamento de Ciencias Biológicas Animales, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Chile.
Antonella
A
Bacigalupo
Verónica
V
Segovia
Alejandro
A
García
Carezza
C
Botto-Mahan
Sylvia
S
Ortiz
Aldo
A
Solari
Mariana
M
Acuna-Retamar
Fernando
F
Torres-Pérez
Pedro E
PE
Cattan
D000818:Animals; D014355:Chagas Disease / Q000469:parasitology / Q000635:transmission; D002677:Chile; D016054:DNA, Protozoan / Q000235:genetics / Q000302:isolation & purification*; D017753:Ecosystem; D005838:Genotype; D006798:Housing; D007303:Insect Vectors / Q000187:drug effects / Q000469:parasitology*; D007306:Insecticides / Q000494:pharmacology; D009693:Nucleic Acid Hybridization / Q000379:methods; D009758:Nymph / Q000187:drug effects / Q000469:parasitology; D012307:Risk Factors; D014224:Triatoma / Q000187:drug effects / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*
D016054:DNA, Protozoan; D007306:Insecticides