Feeding-Site Selection of Lutzomyia longipalpis (Diptera: Psychodidae) on Mice Infected with Leishmania mexicana amazonensis

The feeding behavior of Lutzomyia longipalpis was examined on uninfected mice and on mice infected with Leishmania mexicana amazonensis. Feeding was limited to areas of exposed skin and included the ears, eyelids, feet, nose, and tail. The incidence of landing on specific sites was positively correlated with the surface area of the individual sites on both infected (r = +0.91) and uninfected (r = +0.96) mice, suggesting that selection of landing sites occurred randomly. Probing on infected mice was not a random event. Preferential probing by Lutzomyia longipalpis on cutaneous lesions of infected mice resulted in a frequency of feeding higher than expected on these lesions. Mice infected with Leishmania mexicana amazonensis develop cutaneous lesions that are rich in amastigotes; selective feeding on these lesions by sand flies could facilitate transmission of the Leishmania. Relevance to the epidemiology of leishmaniasis is discussed.