Guimarães-E-Silva Antônia Suely, Silva Soraia de Oliveira, Ribeiro da Silva Rosa Cristina, Pinheiro Valéria Cristina Soares, Rebêlo José Manuel Macário, Melo Maria Norma
Centro de Estudos Superiores de Caxias, Laboratório de Entomologia Médica (LABEM), Universidade Estadual do Maranhão, Caxias, Maranhão, Brazil.
Departamento de Parasitologia, Laboratório de Biologia de Leishmania, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
PLoS One. 2017 Aug 24;12(8):e0179052. doi: 10.1371/journal.pone.0179052. eCollection 2017.
The aims of the study were to determine the blood feeding preferences of sandflies and to identify species of Leishmania that infected phlebotomines in Caxias, Maranhão, Brazil, an area that is highly endemic for leishmaniasis. Sandflies were captured in light traps located in the peridomiciliary environments of randomly selected houses in urban and rural settings between 1800 and 0600 hours on new moon days between March 2013 and February 2015. DNA extracts from 982 engorged female sandflies were submitted to fragment length polymorphism analysis to identify infecting species of Leishmania, and blood sources were identified for 778 of these specimens. Infection by Leishmania infantum was detected in Lutzomyia longipalpis, Lu. whitmani and Lu. termitophila; L. infantum/L. braziliensis in Lu. longipalpis, Lu. whitmani and Lu. trinidadensis; L. shawi in Lu. longipalpis; L. mexicana in Lu. longipalpis; L. braziliensis in Lu. longipalpis and Lu. whitmani; L. guyanensis in Lu. longipalpis and Lu. termitophila; L. amazonensis in Lu. longipalpis and L. lainsoni or L. naiffi in Lu. longipalpis, while Lu. longipalpis and Lu. trinidadensis were infected with unidentified Leishmania sp. Blood sources were identified in 573 individual phlebotomines and the preferred hosts were, in decreasing order, chicken, dog, rodent and human with lower preferences for pig, horse, opossum and cattle. Lu. longipalpis and Lu. whitmani performed mixed feeding on man, dog and rodent, while Lu. longipalpis was the most opportunistic species, feeding on the blood of all hosts surveyed, but preferably on dog/chicken, dog/rodent and rodent/chicken. Our findings reveal the concomitant circulation of Leishmania species that cause visceral leishmaniasis and tegumentary leishmaniasis in the study area, and explain the occurrence of autochthonous human cases of both clinical forms of leishmaniasis in Caxias, Maranhão. The results support our hypothesis that, in the municipality of Caxias, transmission of Leishmania occurs in close proximity to humans.
该研究的目的是确定白蛉的吸血偏好，并识别在巴西马拉尼昂州卡西亚斯感染白蛉的利什曼原虫种类，该地区是利什曼病的高度流行区。在2013年3月至2015年2月期间新月日的18:00至06:00，在城市和农村环境中随机选择房屋的住家周围环境中，用诱虫灯捕获白蛉。对982只饱血雌白蛉的DNA提取物进行片段长度多态性分析，以鉴定感染的利什曼原虫种类，并为其中778个标本确定血源。在长须罗蛉、惠氏罗蛉和嗜白蚁罗蛉中检测到婴儿利什曼原虫感染；在长须罗蛉、惠氏罗蛉和特立尼达拉罗蛉中检测到婴儿利什曼原虫/巴西利什曼原虫；在长须罗蛉中检测到沙氏利什曼原虫；在长须罗蛉中检测到墨西哥利什曼原虫；在长须罗蛉和惠氏罗蛉中检测到巴西利什曼原虫；在长须罗蛉和嗜白蚁罗蛉中检测到圭亚那利什曼原虫；在长须罗蛉中检测到亚马逊利什曼原虫，在长须罗蛉中检测到莱氏利什曼原虫或奈菲利什曼原虫，而长须罗蛉和特立尼达拉罗蛉感染了未鉴定的利什曼原虫种。在573只个体白蛉中确定了血源，首选宿主依次为鸡、狗、啮齿动物和人类，对猪、马、负鼠和牛的偏好较低。长须罗蛉和惠氏罗蛉对人、狗和啮齿动物进行混合吸血，而长须罗蛉是最具机会主义的物种，吸食所有调查宿主的血液，但更喜欢吸食狗/鸡、狗/啮齿动物和啮齿动物/鸡的血液。我们的研究结果揭示了在研究区域内导致内脏利什曼病和皮肤利什曼病的利什曼原虫种类的同时传播，并解释了马拉尼昂州卡西亚斯两种临床形式利什曼病本地人间病例的发生情况。结果支持了我们的假设，即在卡西亚斯市，利什曼原虫的传播发生在人类附近。
