Attraction of Triatoma infestans (Klug) to adhesive yeast-baited trap under laboratory conditions

Abstract

Existing methods to detect domestic triatomines have low sensitivity. As early house infestation detection is epidemiologically important, the exploration of better methods is required. Hence, we measured the attractiveness of a yeast-baited trap to adults and nymphs of Triatoma infestans, under laboratory conditions. The assays were conducted in an experimental arena, with an experimental and a control traps placed at opposite sides and one refuge in the center area. Insects were released and the number of triatomines in the yeast and control traps were counted, after 3, 6 and 24 h of the beginning of the experiment. We used generalized linear models within a multimodel inference approach to model the number of insects in the trap, using insect age classes, time after assay initiation and date of the experiment as predictors. Our results show that the attraction to CO2 depends upon the life stage of the insects. During the 24 h of experiment a constant number of adults (3.5; 95% CI [3.0; 4.1]) were attracted to the yeast trap, while nymphs show attraction only up to the first three hours after the initiation of CO2 liberation (2.7; 95% CI [2.0; 3.5]). Undoubtedly, the orientation response to chemical cues deserves further studies to be fully understood.