Blood feeding preference of Lutzomyia whitmani (Diptera, Psychodidae) in a transmission area for American cutaneous leishmaniasis in the State of Maranhão, Brazil

Submitted by Sandra Infurna ([email protected]) on 2018-07-12T16:52:12Z No. of bitstreams: 1 elias_lorosa_etal_IOC_2009.pdf: 164142 bytes, checksum: 88acc7b6e08214339db7b0fece5e5227 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-07-12T17:03:36Z (GMT) No. of bitstreams: 1 elias_lorosa_etal_IOC_2009.pdf: 164142 bytes, checksum: 88acc7b6e08214339db7b0fece5e5227 (MD5)Made available in DSpace on 2018-07-12T17:03:36Z (GMT). No. of bitstreams: 1 elias_lorosa_etal_IOC_2009.pdf: 164142 bytes, checksum: 88acc7b6e08214339db7b0fece5e5227 (MD5) Previous issue date: 2009Universidade Federal do Maranhão. Programa de Pós Graduação em Biodiversidade e Conservação. São Luis, MA, Brasil.Universidade Federal do Maranhão. Programa de Pós Graduação em Biodiversidade e Conservação. São Luis, MA, Brasil.Universidade Federal do Maranhão. Programa de Pós Graduação em Biodiversidade e Conservação. São Luis, MA, Brasil.Universidade Federal do Maranhão. Programa de Pós Graduação em Biodiversidade e Conservação. São Luis, MA, Brasil.Universidade Federal do Maranhão. Laboratório de Entomologia e Vetores. São Luis, MA, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departamento de Entomologia. Rio de Janeiro, RJ. Brasil.Universidade Federal do Maranhão. Departamento de Biologia. São Luis, MA, Brasil.Universidade Federal do Maranhão. Departamento de Biologia. São Luis, MA, Brasil.O objetivo deste estudo foi determinar as fontes de alimento sanguíneo de fêmeas de Lutzomyia whitmani, espécie de flebotomíneo incriminada no Maranhão como principal vetor da leishmaniose cutânea americana. Para isso, 70 fêmeas desta espécie coletadas no município de Axixá, área com um dos maiores números de casos de leishmaniose cutânea americana em humanos no Maranhão, foram analisadas utilizando a técnica da precipitina. Dos indivíduos analisados, 90% apresentaram reação a algum tipo de antissoro e dentre estes, 73% apresentaram reações do tipo simples com predominância para sangue de galinha (22,2%), roedor (14,3) e humano (12,7%). Nas reações duplas predominaram as combinações galinha/humano (6,3%), galinha/gambá (4,8%), boi/humano e gambá/humano (3,2%). Assim, concluímos que seres humanos, animais domésticos e sinantrópicos constituem fonte alimentar sanguínea para Lutzomyia whitmani podendo desempenhar um papel importante no ciclo de transmissão da leishmaniose cutânea americana explicando os casos da doença em Axixá.The aim of this study was to determine the sources of blood meals for females of Lutzomyia whitmani, a phlebotomine species incriminated as the main vector for American cutaneous leishmaniasis in Maranhão. For this, 70 Lutzomyia whitmani females were collected in the municipality of Axixá, an area with one of the greatest numbers of cases of American cutaneous leishmaniasis in humans in Maranhão. They were analyzed using the precipitin technique. Ninety percent of the specimens showed a reaction to some type of antiserum positive immune reaction, among which 73% presented single reactions, with predominance for chicken blood (22%), rodent blood (14.3%) and human blood (12.7%). Among the double reactions, the predominant combinations were chicken/human (6.3%), chicken/opossum (4.8%), ox/human (3.2%) and opossum/human (3.2%). Thus, we conclude that humans and domestic and synanthropic animals are blood meal sources for Lutzomyia whitmani and may play an important role in the transmission cycle for American cutaneous leishmaniasis, thus explaining the cases of this disease in Axixá

Leishmania infection in humans, dogs and sandflies in a visceral leishmaniasis endemic area in Maranhão, Brazil

Leishmania infection in humans, dogs and sandflies was examined in the endemic visceral leishmaniasis (VL) municipality of Raposa, state of Maranhão, Brazil. In this study, we examined Leishmania chagasi infection in the blood serum of both humans and Canis familiaris and the natural Leishmania sp. infection rate in the sandfly vector, Lutzomyia longipalpis. Enzyme-linked immunosorbent assay, indirect immunofluorescence reaction and polymerase chain reaction were performed to detect Leishmania infections in humans, dogs and sandflies, respectively. Overall, 186 out of 986 studied human beings were infected with L. chagasi parasites, representing an infection prevalence of 18.9%. An even higher infection rate was detected in dogs, where 66 (47.8%) out of 138 were infected. Among all Lu. longipalpis captured (n = 1,881), only 26.7% were females. The Leishmania infection frequency for the vector Lu. longipalpis was 1.56%. Remarkably, all infected sandflies were found in the peridomiciliary area. Furthermore, a high incidence of asymptomatic forms of VL in the human and canine populations was observed. The results of this study suggest autochthonous transmission of L. chagasi in this endemic area for visceral leishmaniasis because infection by Leishmania sp. was identified in all important elements of the transmission chain