Epidemiological patterns of cutaneous leishmaniasis in Panama. I. Epidemics among small groups of settlers.

Epidemic of cutaneous leishmanniasis among a small group of people established in a Panamanian forested area was studied. The first settlers arrived in June 1971, and by June 1973 there were 37 persons, 33 of whom had no previous history of the disease. Epidemiological surveys were made in June 1973 and March 1974. The disease developed in 14 (42.4%) of the 33 susceptible persons by June 1973, with an exposure time ranging from one to 14 months. The last case occurred in April 1973, and no new cases were observed during the ensuing 11 months. Two (15.4%) of 13 dogs examined were found with cutaneous leishmaniasis, but none of 41 feral mammals studied, mainly terrestrial rodents, was infected. Four leishmanial strains characterized, three from patients and one from a dog, were identified as Leishmania braziliensis. Phlebotomine sandfly population composition was studied and the probable vectors involved in the transmission to man were determined.