Comparison of some behavioral and physiological feeding parameters of Triatoma infestans Klug, 1834 and Mepraia spinolai Porter, 1934, vectors of Chagas disease in Chile

There are two vectors of Chagas disease in Chile: Triatoma infestans and Me praia spinolai. We studied the feeding behavior of these species, looking f or differences which could possibly explain the low impact of the latter sp ecies on Chagas disease. Both species used thermal cues to locate their fee ding source and consumed a similar volume of blood which was inversely rela ted to the bod weight before the meal and directly related to the time betw een meals. The average time between bites were 6.24 and 10.74 days. The ave rage bite of M. spinolai lasted 9.68 min, significantly shorter than the 19 .46 min for T. infestans. Furthermore, while T. infestans always defecated on the host, this behavior was observed in M. spinolai in only one case of 27 (3.7%). the delay between the bites and defecation was very long in M. s pinolai and short in T. infestans. These differences may affect the reduced efficiency of transmission of Chagas infection by M. spinolai.