Epidemiological patterns of cutaneous leishmaniasis in Panama. III. Endemic persistence of the disease.

Endemic persistence of cutaneous leishmaniasis is described in El Aguacate, a community established in the forest of central Panama about 75 years ago. Physiographic pecularities partially isolate El Aguacate from other villages in the region. Some of the original forest environment has been preserved and man-biting species of phlebotomine sandflies were abundant as was the two-toed sloth, Choloepus hoffmanni, the principal reservoir host of Leishmania braziliensis in Panama. The inhabitants, as well as their dogs, were examined for natural leishmaniasis in 1969 and 1973. Mammals and phlebotomine sandflies were collected from 1968 to 1973 in a search for reservoir hosts and potential vectors of the disease. Similar studies were undertaken in two nearby villages during 1968 and 1969. L. braziliensis has persisted for many years in El Aguacate, and infection is acquired during childhood. Dogs also were found naturally infected, and the two-toed sloth showed yearly infection rates up to 47.8%. Parasites were demonstrated from a night monkey, Aotus trivirgatus.