Situación de mepraia spinolai: vector silvestre de la enfermedad de Chagas en Chile en relación con otros vectores desde la perspectiva de sus fuentes de alimentación / Situation of mepraia spinolai: wild vector of Chagas' disease in Chile compared with other vectors from the perspective of their alimentary profile

Background: Three triatomine species, Triatoma infestans, Mepraia spinolai and Mepraia gajardoi, are vectors for Chagas disease in Chile. Aim: To compare the alimentary profile of Mepraia spinolai, the Chilean wild vector of Chagas disease, with that of the several other triatomines. Material and methods: The alimentary profile of Mepraia spinolai was compared with that of other triatomines using cluster analysis (Q and R techniques) with the Jaccard index. Results: Three basic groups of triatomines were identified: domestic, wild and specialists, such as P. coreodes and C. pilosa. Our wild vector M. spinolai was in an intermediate position between wild and domestic clusters, grouping with T. rubrovaria, T. sordida and P. megistus. The feeding sources, animals of the domestic and peri-domestic habitat and wild animals, corresponded to the clusters of the two groups. Conclusions: Mepraia spinolai, being a preponderantly wild species, approaches human dwellings and obtains food from domestic animals and eventually, from human blood

Infección tripano-triatomina de triatoma spinolai en una zona de riesgo epidemiológico / Tripano-triatomine infection of triatoma spinolai in a zone with epidemiological risk

Triatoma spinolai is the only wild vector for Chagas disease in Chile and its epidemiological importance is being studied. To study the proportion of insects infected with Trypanosoma cruzi (tripano-triatomine index) in a zone with epidemiological risk in the Metropolitan Region of Chile, 492 specimens of triatoma spinolai were collected in 4 sites of a quarry zone, 14 kilometers north of Santiago. Their maturity and the presence of Trypanosoma cruzi in their intestinal contents were determined. Mean Tripano-triatomine index was 26.02ñ2 percent (range 0 to 34 percent in different sites). The proportion of infected insects increased along with the maturity and 58 percent of adult specimens were infected. There was a seasonal variation of the proportion of infected specimens being lower in march and June and higher in July and February. The studied zone has a potential epidemiological risk for the transmission of Chagas disease by Triatoma spinolai