Department of Parasitology, West China School of Basic Medical Sciences and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China.
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China.
PLoS One. 2019 Apr 25;14(4):e0210681. doi: 10.1371/journal.pone.0210681. eCollection 2019.
Leishmaniasis caused by protozoan parasite Leishmania is a neglected disease which is endemic in the northwest of China. Reptiles were considered to be the potential reservoir hosts for mammalian Leishmaniasis, and Leishmania had been detected in lizards from the epidemic area in the northwest of China. To date, few studies are focused on the natural infection of snakes with Leishmania.
In this study, 15 snakes captured from 10 endemic foci in the northwest of China were detected Leishmania spp. on the base of mitochondrial cytochrome b, heat shock protein 70 gene and ribosomal internal transcribed spacer 1 regions, and identified with phylogenetic and network analyses.
In total, Leishmania gene was found in 7 snakes. The phylogenetic inference trees and network analysis suggests that the species identification was confirmed as Leishmania donovani, L. turanica and L. (Sauroleishmania) sp.
Our work is the first time to investigate the natural Leishmania spp. infection of snakes in the northwest of China. Mammalian Leishmania (L. donovani and L. turanica) was discovered in snakes and the reptilian Leishmania (Sauroleishmania sp.) was closely related to the clinical strains both prompt the importance of snakes in the disease cycle. To indicate the epidemiological involvement of snakes, a wide sample size in epidemic area and the pathogenic features of reptilian Leishmania promastigotes are recommended in the future research.
由原生动物寄生虫利什曼原虫引起的利什曼病是一种被忽视的疾病，在中国西北部流行。爬行动物被认为是哺乳动物利什曼病的潜在储存宿主，在中国西北部的流行地区已从蜥蜴中检测到利什曼原虫。迄今为止，很少有研究关注蛇类的自然感染。
本研究基于线粒体细胞色素 b、热休克蛋白 70 基因和核糖体内部转录间隔区 1 区域，对来自中国西北部 10 个流行地区的 15 条蛇进行了利什曼原虫属检测，并通过系统发育和网络分析进行了鉴定。
共发现 7 条蛇携带利什曼原虫基因。系统发育推断树和网络分析表明，种属鉴定为杜氏利什曼原虫、土耳其利什曼原虫和（Sauroleishmania）sp。
本研究首次调查了中国西北部蛇类的自然利什曼原虫属感染情况。在蛇类中发现了哺乳动物利什曼原虫（杜氏利什曼原虫和土耳其利什曼原虫），而爬行动物利什曼原虫（Sauroleishmania sp.）与临床株密切相关，这提示蛇类在疾病循环中具有重要意义。为了表明蛇类在流行病学上的参与，建议在未来的研究中增加流行地区的样本量，并对爬行动物利什曼原虫前鞭毛体的致病特征进行研究。
