First identification and molecular subtyping of Blastocystis sp. in zoo animals in southwestern China

Lei Deng,Tingmei He,Zhijun Zhong,Hualin Fu,Shanyu Chen,Guangneng Peng,Ziyao Zhou,Yijun Chai,Haifeng Liu,Jingxin Yao,Xiaogang Shi

doi:10.1186/s13071-020-04515-2

Abstract

BackgroundBlastocystis sp. is an anaerobic protozoan that parasitizes many animal hosts and the human gastrointestinal tract, and its pathogenicity is controversial. Captive wildlife may be potential reservoirs for human infection with Blastocystis sp. The present study was performed to investigate the prevalence and subtype distribution of Blastocystis sp. in zoo animals in Sichuan Province, southwestern China.MethodsA total of 420 fresh fecal samples were collected from 54 captive wildlife species in four zoos in southwestern China between June 2017 and September 2019. The prevalence and subtype (ST) genetic characteristics of Blastocystis sp. were determined by PCR amplification of the barcode region of the SSU rRNA gene and phylogenetic analysis.ResultsOverall, 15.7% (66/420) of the animal samples and 20.7% (14/54) of the species tested were shown to be infected with Blastocystis sp. The highest prevalence of Blastocystis sp. was found in Panzhihua Zoo (24.3%), which was significantly higher than that in Chengdu Zoo (6.9%), and Xichang Zoo (2.9%) (P < 0.05). There are also significant differences in the prevalence of Blastocystis sp. among different species (P < 0.05), and the highest of Blastocystis sp. prevalence was observed in white-cheeked gibbon, black great squirrel, and red giant flying squirrel (100%). Subtype analysis of Blastocystis sp. revealed nine subtypes, including six zoonotic STs (ST1-5, and ST8) and three animal-specific STs (ST10, ST14, and ST17), with ST17 as the predominant subtype (26/66) in Blastocystis sp.-positive isolates.ConclusionsTo our knowledge, this is the first report on the prevalence and subtype distribution of Blastocystis sp. among captive wildlife in zoos in southwestern China. This study highlights that these animals may serve as reservoirs for human Blastocystis sp. infections.Graphical

Highlights

Blastocystis sp. is an anaerobic protozoan that parasitizes many animal hosts and the human gastrointestinal tract, and its pathogenicity is controversial
Prevalence of Blastocystis sp. in captive wild animals It is worth noting that the prevalences are the minimum since we used barcoding primers rather than qPCR
66 of 420 (15.7%) fecal samples collected from four animal zoos in China were determined to be Blastocystis sp. positive by polymerase chain reaction (PCR) amplification of the barcode region of the small subunit (SSU) Small subunit ribosomal RNA (rRNA) gene

Summary

Introduction

Blastocystis sp. is an anaerobic protozoan that parasitizes many animal hosts and the human gastrointestinal tract, and its pathogenicity is controversial. Is an anaerobic protozoan that parasitizes many animal hosts and the human gastrointestinal tract, and its pathogenicity is controversial. Captive wildlife may be potential reservoirs for human infection with Blastocystis sp. Blastocystis sp., belonging to the phylum stramenopiles, is a common anaerobic eukaryotic protist that inhabits the gastrointestinal tract of a wide range of hosts, including humans. It is estimated that this parasite has colonized 1 to 2 billion people worldwide based on epidemiological surveys [1]. There is supporting evidence that some human infections. Based on polymorphisms of small subunit (SSU) gene of Blastocystis sp., 22 subtypes (STs) consisting of ST1 to ST17, ST21, and ST23 to ST26 have been identified in humans and domestic and wild animals worldwide [7]. Remarkable genetic diversity was observed among various STs [10], and different STs exhibit diverse biological features, such as drug resistance, pathogenicity, and effects on microbiota [11,12,13]

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