Taeniid cestodes in Tibetan foxes (Vulpes Ferrilata) detected by copro-PCR: Applications and challenges

Zuo Qingqiu; Sun Xiaohui; Wang Xu; Weng Xiaodong; Wang Xiaoming; Ding Youzhong; Xie Fei; Ba Jianfeng; Zou Bin; Tan Wenming; Wang Zhenghuan

doi:10.1016/j.ijppaw.2020.06.008

Taeniid cestodes in Tibetan foxes (Vulpes Ferrilata) detected by copro-PCR: Applications and challenges

Int J Parasitol Parasites Wildl. 2020 Jul 8:12:242-249. doi: 10.1016/j.ijppaw.2020.06.008. eCollection 2020 Aug.

Authors

Zuo Qingqiu¹, Sun Xiaohui¹, Wang Xu², Weng Xiaodong¹, Wang Xiaoming^{1

3}, Ding Youzhong¹, Xie Fei⁴, Ba Jianfeng⁴, Zou Bin⁴, Tan Wenming⁴, Wang Zhenghuan^{1

5

6}

Affiliations

¹ School of Life Sciences, East China Normal University, 500 Dongchuan Rd, Shanghai, 200241, China.
² National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, Key Laboratory of Parasite and Vector Biology, Ministry of Health, 207 Ruijin Rd, Shanghai, 200025, China.
³ Shanghai Science and Technology Museum, 2000 Shiji Rd, Shanghai, 200127, China.
⁴ Shiqu County Center of Disease Control, Renli Rd, Shiqu, Sichuan, 627350, China.
⁵ Joint Translational Science & Technology Research Institute, East China Normal University, 500 Dongchuan Rd, Shanghai, 200241, China.
⁶ Shanghai Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, 500 Dongchuan Rd, Shanghai, 200241, China.

Abstract

Tibetan foxes (Vulpes ferrilata) have been confirmed as the main wild definitive hosts in echinococcosis transmission in the eastern Tibetan Plateau. However, little information is available about the epidemiology in wildlife from the perspective of the Taeniidae family, which is essential knowledge in understanding the epidemiology and phylogeography of cestode species in the Tibetan plateau. Therefore, in this study, we used copro-PCR techniques, by amplifying nad1 and cox1 gene fragments, to detect the taeniid species from Tibetan fox feces collected in Shiqu County, (Sichuan Province, China), eastern Tibetan Plateau. Phylogenetic relationships between amplified sequences and existed Taenia species genotypes were evaluated. Then, the maximum prevalence (positive PCR results from at least one primer pair) and the conservative prevalence (positive PCR results from at least two primer pairs) were calculated. Thirty-six Tibetan fox feces were analyzed. Echinococcus multilocularis (conservative prevalence ± 95% CI: 22.2% ± 13.6%; maximum prevalence ± 95% CI: 33.3% ± 15.4%) and E. shiquicus (2.8 ± 5.4%; 8.3 ± 9.0%) was detected. Meanwhile, DNA fragments of T. polyacantha were detected with high similarity to NCBI sequences (cox1, 94.0%) and to the larva sample DNA sequenced in this study (93.4%), and were supported by phylogenetic analysis. Thus, T. polyacantha might infect Tibetan foxes (5.6% ± 7.5%, 11.1% ± 10.3%). Our limited findings in the epidemiology of parasitic Taenia species suggest that sylvatic transmission cycles for a more species-rich Taeniid community must be established between wild canids and small mammals than just for the two Echinococcus species. Besides, discrepancies in different primer pairs in detecting the taeniid species were evaluated. The sensitivity of some widely used universal primer pairs was poor in detecting Taenia species from canid copro-DNA samples. It is still challenging to the development of effective taeniid species-specific molecular markers especially for non-zoonotic species.

Keywords: Echinococcosis; Taenia polyacantha; Taeniidae; Tibetan fox; Tibetan plateau.