Molecular identification of Trichuris species in long-tailed macaques from Dong Ling Don Chao Pu Park and Kumphawapi Monkey Garden, Northeast Thailand: First report suggesting possible Trichuris ovis infection in non-human primates

This study aimed to molecularly identify Trichuris spp. in long-tailed macaques from two key habitats in Northeast Thailand: Dong Ling Don Chao Pu Park, Amnat Charoen Province, and Kumphawapi Monkey Garden, Udon Thani Province. Genomic DNA was extracted from 13 Trichuris spp. egg samples collected from 13 infected long-tailed macaques, and PCR amplification targeting partial sequences of the 18S rRNA gene and ITS2 region was performed for phylogenetic analysis. Of the 13 Trichuris spp. egg samples, the partial 18S rRNA gene was successfully amplified from six, while ITS2 amplification was unsuccessful. Phylogenetic analysis indicated that four specimens sequenced from Dong Ling Don Chao Pu Park were T. trichiura. In contrast, two specimens sequenced from Kumphawapi Monkey Garden clustered with the only confirmed T. ovis from goat, as well as unconfirmed Trichuris spp. from other ruminant hosts. These findings suggest that the Trichuris spp. in macaques are likely T. ovis; however, the evidence remains inconclusive. Therefore, accurate species identification in this region requires further molecular analysis using additional genetic markers. This study provides the first molecular identification of T. trichiura in long-tailed macaques from Northeast Thailand. Additionally, it is the first report suggesting the possible T. ovis infection in non-human primates. These findings highlight the potential for Trichuris spp. transmission across diverse host species, underscoring the need for enhanced surveillance of parasitic infections in wildlife and livestock, particularly in regions with close human-animal interactions. Continued molecular investigations are essential to elucidate Trichuris spp. transmission dynamics and zoonotic potential, aiding in public health risk mitigation.