海南省白沙黎族自治县中小学生芽囊原虫分子遗传特征分析

Molecular genetic characterization of Blastocystis in primary and middle school students in Baisha Li Autonomous County,Hainan

目的为了解海南省白沙黎族自治县中小学生芽囊原虫感染情况及其亚型分布特征,对该地两所中小学的学生进行了调查研究。方法2021年3—11月,收集海南白沙黎族自治县两所中小学学生的粪便样本。采用PCR方法扩增芽囊原虫核糖体小亚基基因(small subunit ribosomal RNA gene,SSU rDNA),通过序列分析确定芽囊原虫的感染情况和亚型,使用Mega 7软件构建系统发育进化树。同时对不同年级、性别的中小学生芽囊原虫的感染情况进行分析,评估感染相关因素。结果海南省白沙黎族自治县中小学生芽囊原虫感染率为4.1%(13/314),不同年级和性别的中小学生感染率差异无统计学意义(P>0.05)。经序列分析,共鉴定出3种芽囊原虫亚型,分别是ST3(n=7)、ST7(n=4)和ST1(n=2),这些亚型均具有人兽共患特性。结论本研究首次从分子水平对海南地区人群进行芽囊原虫研究,为该地区芽囊原虫病的防控提供了基础数据。多个人兽共患亚型的检出,提示未来需要进一步对该区域的人和动物进行芽囊原虫感染情况进行研究,以探究芽囊原虫可能感染的来源,为该地区芽囊原虫的防控提供科学依据。

Objective To investigate the prevalence and genetic characterization of Blastocystis in primary and middle school students in Baisha Li Autonomous County,Hainan Province,in order to understand the infection status of Blastocystis and its subtype distribution characteristics in this area.Methods From March to November 2021,fecal samples were collected from two primary and middle schools in Baisha Li Autonomous County.Nested PCR targeting the SSU rDNA was employed in this study,sequence analysis were performed to determine the prevalence and subtype.A neighbor-joining tree was built using Mega 7.Meanwhile,the risk factors of the Blastocystis infection among different grades and genders were evaluated.Results The infection rate of Blastocystis was 4.1%(13/314),there was no statistical difference in infection rates among genders and grades(P>0.05).Sequence analysis revealed that three Blastocystis subtypes were identified,namely ST3(n=7),ST7(n=4)and ST1(n=2),all of which have zoonotic potential.Conclusions This is the first report of the identification of Blastocystis in humans in Hainan at the subtype level,and provide the basic data for the prevention and control of Blastocystis in this area.The zoonotic subtypes identified in this area indicated more studies should be taken in humans and various animals,to better evaluate the transmission of Blastocystis and provide scientific support for the prevention and control of Blastocystis.