Departamento de Epidemiologia, Faculdade de Saúde Pública, Universidade de São Paulo, CEP, Cerqueira Cesar, São Paulo, São Paulo, Brazil.
Centro de Controle de Zoonoses, Av. Ecologista de João de Oliveira Ramos de Sá 336, CEP, Chácaras Bartira, Embu das Artes, São Paulo, Brazil.
J Med Entomol. 2021 Mar 12;58(2):830-836. doi: 10.1093/jme/tjaa199.
Visceral leishmaniasis is spreading in Brazil where the main vector of its agent, Leishmania infantum Nicolle, 1908, is the Lutzomyia longipalpis (Lutz & Neiva, 1912) species complex (Diptera: Psychodidae: Phlebotominae), on which many of the activities of the visceral leishmaniasis surveillance program are based. However, there are areas where canine, and/or human cases have been occurring without the presence of this species complex as in the western part of the Greater São Paulo Metropolitan region, where Embu das Artes municipality is situated. In this area, Pintomyia fischeri (Pinto, 1926) has been implicated as potential vector of Le. infantum but so far its natural infection with this parasite has not yet been ascertained. Therefore, the present study sought to investigate the natural infection in sand flies of a CVL focus in Embu das Artes. The sand fly collections were undertaken with Shannon and CDC traps, monthly, between 1800 and 2100 hours from November 2018 to October 2019, inclusive. A total of 951 sand flies (457 males and 494 females), belonging to 10 species, were captured. Pintomyia fischeri was the predominant species (89.5%); of which 426 females were dissected and one of them (0.23%) was found to be harboring flagellates in its midgut. A sample of these flagellates was isolated in culture and characterized by a 234 base pair fragment of Leishmania heat-shock protein 70 gene (hsp70) and restriction fragment length polymorphism with Hae III restriction enzyme as Le. infantum. This finding reinforces previous evidence of Pi. fischeri as a vector of Le. infantum in foci of visceral leishmaniasis and highlights the importance of vector surveillance in areas where this species occurs.
内脏利什曼病正在巴西蔓延,其病原体利什曼原虫的主要媒介是卢茨omyia longipalpis(Lutz&Neiva,1912)物种复合体(双翅目:Psychodidae:Phlebotominae),许多内脏利什曼病监测计划的活动都基于该物种复合体。然而,在某些地区,犬科动物和/或人类病例的发生并没有这种物种复合体的存在,例如大圣保罗大都市区的西部,埃姆布达斯阿特斯市就位于该地区。在该地区,Pintomyia fischeri(Pinto,1926)已被牵连为潜在的利什曼原虫媒介,但迄今为止,尚未确定其对这种寄生虫的自然感染。因此,本研究旨在调查埃姆布达斯阿特斯内脏利什曼病焦点地区沙蝇的自然感染情况。沙蝇采集工作于 2018 年 11 月至 2019 年 10 月期间,每月使用 Shannon 和 CDC 陷阱,在 1800 至 2100 小时之间进行。共捕获 951 只沙蝇(457 只雄性和 494 只雌性),分属于 10 个种。Pintomyia fischeri 是优势种(89.5%);其中 426 只雌性被解剖,其中一只(0.23%)在中肠中发现含有鞭毛。从这些鞭毛中分离出一个样本,并在培养物中通过 234 个碱基对的利什曼原虫热休克蛋白 70 基因(hsp70)片段和 Hae III 限制酶的限制性片段长度多态性进行了特征分析,结果表明该样本为 Le. infantum。这一发现证实了 Pifischeri 先前作为内脏利什曼病流行地区利什曼原虫媒介的证据,并强调了在该物种存在的地区进行媒介监测的重要性。