Competence of the human host as a reservoir for Leishmania chagasi

Harvard School of Public Health. Department of Immunology and Infectious Diseases. Boston, Massachusetts / Universidade Federal do Piauí. Hospital de Doenças Infecto-Contagiosas. Departamento de Medicina Comunitária. Teresina, PI, Brasil.Universidade Federal do Piauí. Hospital de Doenças Infecto-Contagiosas. Departamento de Medicina Comunitária. Teresina, PI, Brasil.Universidade Federal do Piauí. Hospital de Doenças Infecto-Contagiosas. Departamento de Medicina Comunitária. Teresina, PI, Brasil.Ministério da Saúde. Fundação Nacional de Saúde. Instituto Evandro Chagas. Belém, PA, Brasil.Ministério da Saúde. Fundação Nacional de Saúde. Instituto Evandro Chagas. Belém, PA, Brasil.Universidade Federal do Piauí. Hospital de Doenças Infecto-Contagiosas. Departamento de Medicina Comunitária. Teresina, PI, Brasil.Universidade de São Paulo. Instituto de Ciências Biomédicas. Departamento de Parasitologia. São Paulo, SP, Brazil.Harvard School of Public Health. Department of Immunology and Infectious Diseases. Boston, MassachusettsThe failure of control programs for visceral leishmaniasis (VL) that depend on elimination of infected dogs suggests that other reservoir hosts may participate in the transmission cycle. To determine whether persons infected with Leishmania chagasi can infect the vector sand fly, laboratory-reared Lutzomyia longipalpis were allowed to feed on Brazilian subjects with active, cured, and asymptomatic VL and on asymptomatic residents of houses of persons with active VL. Of 3747 insects that had fed, 26 acquired infection from 11 of the 44 persons with active VL, but none acquired infection from the 137 asymptomatic persons. Among persons