Kochi Medical School, Facultad de Medicina, Universidad Catolica Santiago de Guayaquil, Instituto Nacional de Higiene y Medicina Tropical, Kumamoto University School of Medicine, Nihon University School of Medicine, Institute for Laboratory Animals, Kochi Medical School, Nagasaki University School of Medicine, Oita Medical College, Central Florida Research and Education Center, Hospital Cantonal Paute, Institute Oswaldo Cruz, Youngstown State University, Yale University School of Medicine, Nakoku, Kochi, Japan
Between 1986 and 1988, epidemiologic studies were carried out in a small rural community in an Andean region of Ecuador, where cutaneous leishmaniasis is highly endemic. A total of 25 human cases, positive for Leishmania parasites by culture and/or smear, were examined. Fourteen of the cases were in infants less than one year of age, suggesting intradomiciliary transmission of the disease. Clinically, many of these cases were similar to descriptions of “uta,” a form of cutaneous leishmaniasis which occurs in Andean regions of Peru and is reportedly caused by L. peruviana. Of the 11 positive cultures obtained from human cases in the present study, eight were identified by molecular characterization as L. mexicana and three were identified as L. major-like. Two additional isolates of L. mexicana were also made from an infected dog and from a sand fly, Lutzomyia ayacuchensis, living in the region, thus implicating the latter species as possible reservoir and vector, respectively, of L. mexicana in this highland community. The significance and validity of recent isolates of L. major-like parasites from the New World are also discussed.