黑龙江中俄边境口岸全沟硬蜱中分离到人巴贝西原虫

    付维明 何 浩 呼满霞 崔永民 杨丽炜

    （黑龙江出入境检验检疫局，哈尔滨 150001）

    摘要 〔目的〕了解中俄边境口岸人巴贝西原虫在蜱体内的感染携带情况及病原基因特征，以便采取必要的防控措施。〔方法〕用从黑龙江中俄边境口岸采集到的全沟硬蜱叮咬清洁级的SCID小鼠，而后，利用微气固相分离技术从被叮咬的SCID小鼠中分离人巴贝西原虫。〔结果〕涂片观察可见血细胞内呈现典型的四分体和环状体。离体培养血细胞中亦观察到人巴贝西原虫的生长。核糖体小亚基的基因序列分析表明，新分离到的人巴贝西原虫是微小巴贝西原虫，与密山株和日本神户株具有高度同源性。本批样本中，雌性全沟硬蜱的感染率为2.7%～4.0%。〔结论〕中俄边境口岸存在人巴贝西原虫的自然疫源地，存在人感染的风险，检验检疫部门应采取必要的防范措施，防止巴贝西原虫病传入传出。

    关键词 人巴贝西原虫；全沟硬蜱；微气固相分离技术；分离；口岸

    〔中图分类号〕　R184.39　〔文献标识码〕　B

    Babesia Microti-like Rodent ParasitesIsolated from Ixodes Persulcatus （Acari: Ixodidae） at China-RussiaPorts of Heilongjiang Province   Fu Weiming, He Hao, HuManxia, Cui Yongmin, Yang Liwei. Heilongjiang Entry-exit Inspectionand Quarantine Bureau, Harbin 150001,China.

    [Abstract]   Objective  To explore the fact that the China-Russia border of Heilongjiangprovince had been a human Babesia disease natural focus, to isolatea Babesia microti-like rodent parasite from the tick, and tocollect Ixodes persulcatus from the forest area of Heilongjiangprovince.  Methods   The collected Ixodexpersulcatus were allowed to feed on specific pathogen-free SCIDmice and red blood cells from the mice were used to isolate Babesiaspp. with the microareophilous stationary-phase culturetechnique.  Results Paired and tetrad forms of merozoites wereobserved by light microscope in red blood cells of SCID mice. Invitro growth of the parasites was also achieved in miceerythrocytes, which indicated the presence of Babesia spp. inIxodex persulactus. To further identify the Babesia species,polymerase chain reaction screening and subsequent sequencing ofnuclear small subunit ribosomal RNA （nss-rRNA） was employed. Theresults indicate that the observed parasites might be an isolatestrain responsible for human babesiosis - Babesia microti -whichhas 99.3% identity with that of Babesia microti isolate RcM5201（AB112050） from Mishan in Heilongjiang and Kobe isolates fromJapan. In addition, the infection rate of Babesia microti in Ixodexpersulcatus ticks in the region was 2.7%~4.0% in adult females andno infection in males.   Conclusion   Thoughthe infection rate is low, the high attack frequency of tickspecies on local residents indicates the risk of human babesiosisin the region and the necessary of precautionary measures.

    [Key words]   Babesia microti;Ixodes persulcatus； Microareophilous stationary-phase culturetechnique;Isolation; Port