FACTORS AFFECTING HOST PREFERENCE OF LUTZOMYIA-EVANSI (DIPTERA, PSYCHODIDAE), A VECTOR OF VISCERAL LEISHMANIASIS IN COLOMBIA

Previous studies have shown the sandfly Lutzomyia evansi to be the vec tor of Leishmania chagasi in northern Colombia. A longitudinal survey during seven months on the host preference of Lutzomyia evansi was con ducted in the visceral leishmaniasis focus of San Andres de Sotavento, Colombia. Host preference was determined by presenting sandflies with a choice of three baits (human, and the reservoirs dog and opossum) a nd a blank control in specially designed cone traps. A rotational expe rimental design involved 56 trap nights in which the effect of bait, p roximity to forest and season could be distinguished from the potentia lly confounding factors of site and day to day variation. From a total of 598 sandflies caught during all experiments, females and males of Lutzomyia evansi accounted for 93.8% of the captures in the baited tra ps. Overall, human attracted the greatest number of sand flies, follow ed by the other two baits. Attraction and feeding success showed signi ficant differences (P < 0.0001) between baits.