背景:Onchocercidae是丝虫线虫家族,具有几种医学或兽医学重要性。微丝虫存在于血液和/或真皮中,并且通常通过血液样品的显微镜检查或皮肤活检在人类中诊断。这项研究的主要目的是评估是否可以在野生非人灵长类动物(NHP)的粪便样本中检测到丝虫DNA,检测到的寄生虫是否与感染人类的寄生虫密切相关,以及粪便中的丝虫DNA检测是否与线虫的共感染有关(食道和Necatorsp。)已知在以宿主肠粘膜为食时会引起失血。
方法:共分析了来自喀麦隆和加蓬的6种NHP的315个粪便样本。PCRs靶向cox1和12SrDNA基因的DNA片段,为了检测丝虫的存在,和内部转录间隔区2(ITS2),检测食管造口的存在。和Necatorsp。感染。
结果:在分析的315个样品中,121产生与Onchocercidae参考序列具有>90%同源性的序列。然而,63%的12SrDNA和78%的cox1基因序列可用于系统发育分析,并且12SrDNA基因的扩增显示出比cox1片段的扩增更少的辨别能力。系统发育分析表明,从加蓬的五个黑猩猩DNA粪便样本和喀麦隆的两个样本中获得的cox1序列与具有高引导支持的Mansonellaperstans聚集在一起。其余的大部分序列聚集在曼森氏菌属中,但该物种无法解决。在调查的NHP物种中,丝虫DNA检测与食管气孔之间存在显着关联。和Necatorsp。仅在大猩猩中观察到感染。
结论:据我们所知,这是第一个报告来自Mansonellaspp的DNA的研究。在粪便样本中。我们的研究结果对野生动物中这些寄生虫的多样性和丰度提出了质疑,它们作为热带水库的作用及其人畜共患传播的潜力。未来的研究应该集中在检测在人类和NHP中循环的变异,并改进分子信息,以解析或支持基于形态学描述的分类学分类。
BACKGROUND: The Onchocercidae is a family of filarial nematodes with several species of medical or veterinary importance. Microfilariae are found in the blood and/or the dermis and are usually diagnosed in humans by microscopy examination of a blood sample or skin biopsy. The main objectives of this study were to evaluate whether filariae DNA can be detected in faecal samples of wild non-human primates (NHPs), whether the detected parasites were closely related to those infecting humans and whether filarial DNA detection in faeces is associated with co-infections with nematodes (Oesophagostumum sp. and
Necator sp.) known to cause blood loss while feeding on the host intestinal mucosa.
METHODS: A total of 315 faecal samples from 6 species of NHPs from Cameroon and Gabon were analysed. PCRs targeted DNA fragments of cox1 and 12S rDNA genes, to detect the presence of filariae, and the internal transcribed spacer 2 (ITS2), to detect the presence of Oesophagostomum sp. and
Necator sp. infections.
RESULTS: Among the 315 samples analysed, 121 produced sequences with > 90% homology with Onchocercidae reference sequences. However, 63% of the 12S rDNA and 78% of the cox1 gene sequences were exploitable for phylogenetic analyses and the amplification of the 12S rDNA gene showed less discriminating power than the amplification of the cox1 fragment. Phylogenetic analyses showed that the cox1 sequences obtained from five chimpanzee DNA faecal samples from Gabon and two from Cameroon cluster together with Mansonella perstans with high bootstrap support. Most of the remaining sequences clustered together within the genus Mansonella, but the species could not be resolved. Among the NHP species investigated, a significant association between filarial DNA detection and Oesophagostomum sp. and
Necator sp. infection was observed only in gorillas.
CONCLUSIONS: To our knowledge, this is the first study reporting DNA from Mansonella spp. in faecal samples. Our results raise questions about the diversity and abundance of these parasites in wildlife, their role as sylvatic reservoirs and their potential for zoonotic transmission. Future studies should focus on detecting variants circulating in both human and NHPs, and improve the molecular information to resolve or support taxonomy classification based on morphological descriptions.