BACKGROUND Parasitic trichostrongyloid nematodes have a worldwide distribution in ruminants and frequently have been reported from humans in Middle and Far East, particularly in rural communities with poor personal hygiene and close cohabitation with herbivorous animals. Different species of the genus Trichostrongylus are the most common trichostrongyloids in humans in endemic areas. Also, Ostertagia species are gastrointestinal nematodes that mainly infect cattle, sheep and goats and in rare occasion humans. The aim of the present study was to identify the trichostrongyloid nematodes obtained from a familial infection in Guilan province, northern Iran, using morphological and molecular criteria. METHODS After anthelmintic treatment, all fecal materials of the patients were collected up to 48 h and male adult worms were isolated. Morphological identification of the adult worms was performed using valid nematode keys. Genomic DNA was extracted from one male worm of each species. PCR amplification of ITS2-rDNA region was carried out, and products were sequenced. Phylogenetic analysis of the nucleotide sequence data was performed using MEGA 6.0 software. RESULTS Adult worms expelled from the patients were identified as T. colubriformis, T. vitrinus and Teladorsagia circumcincta based on morphological characteristics of the males. Phylogenetic analysis illustrated that each species obtained in current study was placed together with reference sequences submitted to GenBank database. CONCLUSIONS The finding of current study confirms the zoonotic aspect of Trichostrongylus species and T. circumcincta in inhabitants of Guilan province. The occurrence of natural human infection by T. circumcincta is reported for the first time in Iran and the second time in the world.

中文翻译：

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伊朗北部桂兰省的Teladorsagia circumcincta和Trichostrongylus种的人畜共患病传播：分子和形态学特征。

背景技术寄生三线虫线虫在反刍动物中分布广泛，并且经常从中东和远东地区的人类中报告，特别是在个人卫生差且与食草动物同居的农村社区。Trichostrongylus属的不同物种是人类在流行地区最常见的Trichostrongyloids。另外，子宫震颤种是胃肠道线虫，主要感染牛，绵羊和山羊，并在极少数情况下感染人类。本研究的目的是使用形态和分子标准，鉴定从伊朗北部桂兰省的一家家族感染中获得的线粒体线虫。方法驱虫后至48 h收集患者所有粪便，分离出成虫。使用有效的线虫钥匙对成虫进行形态学鉴定。从每个物种的一只雄虫中提取基因组DNA。进行ITS2-rDNA区域的PCR扩增，并对产物进行测序。使用MEGA 6.0软件进行核苷酸序列数据的系统发生分析。结果根据男性的形态学特征，从患者身上排出的成虫被鉴定为co.colubriformis，T.vitrinus和Teladorsagia circumcincta。系统发育分析表明，将当前研究中获得的每个物种与参考序列一并提交给GenBank数据库。结论本研究的发现证实了桂兰省居民的毛圆线虫种和圆环线虫的人畜共患病方面。