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. 2019 Oct 9:10:274-280.
doi: 10.1016/j.ijppaw.2019.10.001. eCollection 2019 Dec.

Molecular identification and phylogenetic analysis of Cryptosporidium, Hepatozoon and Spirometra in snakes from central China

Xiao Xiao  1   2 , Rui Qi  1 , Hui-Ju Han  1 , Jian-Wei Liu  1 , Xiang-Rong Qin  1 , Li-Zhu Fang  1 , Chuan-Min Zhou  1 , Xiao-Qing Gong  1 , Si-Cong Lei  1 , Xue-Jie Yu  1
Affiliations

Molecular identification and phylogenetic analysis of Cryptosporidium, Hepatozoon and Spirometra in snakes from central China

Xiao Xiao et al. Int J Parasitol Parasites Wildl. .

Abstract

Snakes are popular as food and traditional medicine in China. However, information about parasitic and bacterial infections in snakes from China is scarce. We investigated the prevalence of selected zoonotic agents including Cryptosporidium, Hepatozoon and Spirometra, in snakes in central China from June to October in 2018 by PCR amplification using parasite-specific primers. PCR amplification and DNA sequencing showed that 10.1% (15/149) of snakes were positive for Cryptosporidium spp., while 2.7% (4/149) were positive for Hepatozoon. Additionally, we found 36.9% (55/149) of snakes were infected with Spirometra erinaceieuropaei. The spargana burden per infected snake ranged from 1 to 26. BLAST and phylogenetic analysis of small subunit ribosomal RNA (SSU rRNA) gene and 60-kDa glycoprotein (gp60) gene showed that the parasites belonged to Cryptosporidium parvum genotype IIdA15G1, C. baileyi, C. serpentis and a Hepatozoon species. We conclude that intensively farmed snakes excrete C. parvum and C. baileyi oocysts due to ingestion of infected feeder animals, and that wild snakes in central China were commonly infected with S. erinaceieuropaei, suggesting that eating improperly cooked snakes could be risky to human health.

Keywords: Cryptosporidium; Hepatozoon; Snake; Spirometra; Zoonotic.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Image 1
Graphical abstract
Fig. 1
Fig. 1
Maximum likelihood phylogenetic tree based on the SSU gene of Cryptosporidium. The phylogenetic tree SSU gene (834bp) was constructed by using the Kimura 2-parameter model with MEGA 7.0 and the bootstrap values were calculated with 1000 replicates. Representative sequences of Cryptosporidium detected in snakes in this study are in bold print and marked by circles. Scale bar indicates nucleotide substitutions per site.
Fig. 2
Fig. 2
Maximum likelihood phylogenetic tree based on the 18S rRNA gene of Hepatozoon. The phylogenetic tree was constructed with the 18S rRNA gene sequences (670bp) by using the General time reversible model with MEGA 7.0; the bootstrap values were calculated with 1000 replicates. Representative sequences of Hepatozoon detected in this study are in bold print and marked by circles. Scale bar indicates nucleotide substitutions per site.
Fig. 3
Fig. 3
Maximum likelihood phylogenetic tree of Spirometra based on the cox1 gene. The tree was constructed with the cox1 sequences (444bp) by using the Kimura 2-parameter model with MEGA 7.0; we calculated bootstrap values with 1000 replicates. The representative sequence of Spirometra spagarnas isolated from snakes in this study are in bold print and marked by circles. Scale bar indicates nucleotide substitutions per site.
See this image and copyright information in PMC

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