Department of Parasitology, Tokai University School of Medicine, Isehara, Japan; Graduate School of Human Life and Ecology, Osaka Metropolitan University, Osaka, Japan.
Central Department of Zoology, Institute of Science and Technology, Tribhuvan University, Kathmandu, Nepal.
Acta Trop. 2024 Oct;258:107340. doi: 10.1016/j.actatropica.2024.107340. Epub 2024 Jul 30.
Entamoeba species infect humans and non-human primates, raising concerns associated with potential zoonotic transmission. Therefore, the prevalence of human Entamoeba infections is crucial for its management in areas, where macaques exhibit high infection rates. Previously, we demonstrated prevalent E. nuttalli infections in rhesus macaques in Kathmandu, Nepal. In this study, we surveyed Entamoeba infection among 185 schoolchildren from two schools visited by wild rhesus macaques to assess the risk of transmission. PCR-based screening for Entamoeba species identified E. coli in 13 % and E. dispar in 0.5 % of the human stool samples. However, E. nuttalli and E. chattoni infections, prevalent in macaques, were not detected in human samples. This suggests that Entamoeba spp. are not transmitted through macaques in the school environment. We surveyed the rhesus macaques living in the temple near schools as well as the rhesus and Assam macaques inhabiting Shivapri Nagarjun National Park, Kathmandu. Among the 49 macaque stool samples, E. chattoni, E. coli, E. nuttalli, and E. dispar were detected in 92 %, 86 %, 41 %, and 18 % of the samples, respectively. Notably, E. dispar infections in macaques were mostly prevalent in the temple. A sample isolated from Nagarujun showed an identical genotype at two tRNA-linked short tandem repeat loci to that of E. dispar isolated from humans, suggesting potential transmission from humans to macaques. Genotypic analysis of cultured E. nuttalli strains obtained from the macaques colonizing three locations demonstrated that the geographical distance rather than differences in macaque species played a crucial role in the genetic diversity of the parasites. The phylogenetic tree of E. nuttalli strains, including the previously isolated strains, reflected the geographical distribution of the isolation sites. This study sheds light on the intricate dynamics of Entamoeba transmission and genetic diversity in macaques and humans.
人体中存在的内阿米巴种属会感染人类和非人类灵长类动物，这引起了人们对内阿米巴种属潜在的人畜共患传播的关注。因此，在灵长类动物感染率较高的地区，人类内阿米巴种属的感染率是其管理的关键。之前，我们在尼泊尔加德满都的恒河猴中发现了普遍存在的棘阿米巴纳氏变种感染。在这项研究中，我们对两所被野生恒河猴光顾的学校的 185 名学童进行了内阿米巴种属感染调查，以评估传播风险。基于 PCR 的内阿米巴种属筛查在 13%的人类粪便样本中发现了大肠杆菌，在 0.5%的样本中发现了迪斯帕内阿米巴。然而，在恒河猴中普遍存在的棘阿米巴纳氏变种和棘阿米巴卡顿变种在人类样本中没有被检测到。这表明在学校环境中，内阿米巴种属不会通过恒河猴传播。我们还对学校附近寺庙中生活的恒河猴以及加德满都 Shivapri Nagarjun 国家公园中栖息的恒河猴和 Assam 猴进行了调查。在 49 份恒河猴粪便样本中，分别在 92%、86%、41%和 18%的样本中检测到了棘阿米巴卡顿变种、大肠杆菌、棘阿米巴纳氏变种和迪斯帕内阿米巴。值得注意的是，在寺庙中，恒河猴的迪斯帕内阿米巴感染最为普遍。从 Nagarujun 分离出的一个样本在两个与 tRNA 相连的短串联重复基因座上的基因型与从人类分离出的迪斯帕内阿米巴相同，表明可能存在从人类到恒河猴的传播。对从三个地点定居的恒河猴中分离出的培养棘阿米巴纳氏变种菌株进行基因分析表明，地理位置的差异而不是恒河猴种属的差异在寄生虫的遗传多样性中起着关键作用。包括之前分离出的菌株在内的棘阿米巴纳氏变种菌株的系统发育树反映了分离地点的地理分布。这项研究揭示了内阿米巴在灵长类动物和人类中的传播和遗传多样性的复杂动态。
