Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 06726, Mexico.
Department of Research in Medical Entomology, Commemorative Gorgas Institute for Health Study, Panama 0816-02593, Panama.
Parasitol Int. 2021 Jun;82:102286. doi: 10.1016/j.parint.2021.102286. Epub 2021 Jan 21.
Phlebotomine sand flies are considered the main vectors of Leishmania, the causal agents of leishmaniasis, which is a serious emerging public health problem worldwide. The use of biological control alternatives, like endosymbiotic bacteria (Wolbachia and Rickettsia), have been proposed to decrease sand fly populations and reduce Leishmania transmissions, yet only few records on the detection of Wolbachia or Rickettsia in sand flies are available worldwide. The aim of this study was to perform the molecular detection of Rickettsial agents associated with sand flies from the last patch of a rainforest in south-eastern Mexico, where a high prevalence of Leishmania infantum has been reported. Sampling effort of sand flies covered 300 trap-nights between 2011 and 2013, and a total of 925 specimens from twelve species were morphologically identified. Using PCR techniques, we identified a new lineage of the endosymbionts Rickettsia in Psathyromyia aclydifera (prevalence of 19.54%), and Wolbachia in Psathyromyia shannoni and Lutzomyia sp. (prevalence of 25%). The detected Wolbachia lineage was similar to the wWhi strain found in Pa. shannoni from Colombia and Nyssomyia whitmani from Brazil; whereas the identified Rickettsia represents a new lineage worldwide. This is the first record of Rickettsial agents associated to sand flies from this region, yet it remains for analysed if these bacteria possibly play a role as vector control agents, capable of reducing the sand fly populations in Mexico.
嗜人按蚊被认为是利什曼原虫的主要传播媒介，而利什曼原虫是导致利什曼病的病原体，这是一个在全球范围内严重的新兴公共卫生问题。已经提出了使用生物控制替代物（共生细菌[沃尔巴克氏体和立克次氏体]）来减少沙蝇种群并减少利什曼病传播的方法，但全球范围内只有少数关于沙蝇中沃尔巴克氏体或立克次氏体检测的记录。本研究的目的是在墨西哥东南部最后一片雨林中进行与沙蝇相关的立克次体病原体的分子检测，该地区报告了利什曼原虫婴儿的高流行率。沙蝇的采样工作在 2011 年至 2013 年期间共进行了 300 个诱捕夜，共鉴定了 12 种 925 个标本。使用 PCR 技术，我们在 Psathyromyia aclydifera 中鉴定出了一种新的共生体 Rickettsia （流行率为 19.54％），并在 Psathyromyia shannoni 和 Lutzomyia sp. 中鉴定出了 Wolbachia （流行率为 25％）。检测到的沃尔巴克氏体谱系与在哥伦比亚的 Pa. shannoni 和巴西的 Nyssomyia whitmani 中发现的 wWhi 菌株相似；而鉴定出的立克次氏体代表了全球范围内的一个新谱系。这是该地区与沙蝇相关的立克次体病原体的首次记录，但仍需分析这些细菌是否可能作为控制媒介的代理，有能力减少墨西哥的沙蝇种群。
