Feeding preferences of Triatoma dimidiata maculipennis in Yucatan, Mexico.

To determine whether a low preference for human blood by Triatoma dimidiata maculipennis Stal, 1859, the only known vector of Chagas' disease in Yucatan, Mexico, would account for the low prevalence of antibodies to Trypanosoma cruzi in man in the area, the intestinal contents of 924 bugs were tested against antisera to blood antigens of chicken, opossum, dog, bat, monkey, pig, goat, rabbit, horse, human, rat, ox, cat, and armadillo. Although the chicken was the primary host, man was fed upon frequently; thus, the hypothesis was rejected. Other explanations must be found for the relative lack of antibodies against T. cruzi in humans in Yucatan.