摘要
目的描述山西省2007年Ⅰ型疫苗衍生脊髓灰质炎(脊灰)病毒(Vaccine-derived Poliovirus,VDPV)的基因特征,分析该VDPV的来源及对当地维持无脊灰的影响。方法对山西省2007年1例急性弛缓性麻痹(Acute Flaccid Paralysis,AFP)病例采集的双份粪便标本进行病毒分离,并对分离到的脊灰病毒(CHN11061株)进行VP1编码区基因核苷酸序列测定和分析,然后与国内外报道的其它Ⅰ型VDPV构建亲缘进化树。结果从该AFP病例的双份粪便标本中分离到2株Ⅰ+Ⅱ+Ⅲ混合型脊灰病毒,其中Ⅰ型毒株的VP1编码区基因核苷酸序列与PⅠ/赛宾(Sabin)疫苗株相比变异率≥1.0%,根据世界卫生组织(WHO)的标准鉴定为Ⅰ型VDPV。VP1编码区基因进化树图表明,山西省2007年Ⅰ型VDPV与国内外至今发现的其它VDPV进化距离较远,是新发现的VDPV,不属于循环着的(Circulating)VDPV(cVDPVs),同时无证据证明患儿为免疫缺陷患者,因此将这2株VDPV归类为Ⅰ型未分类的(Ambiguous)VDPV(aVDPV)。结论结合山西省2007年Ⅰ型VDPV的基因特征和当地口服脊灰减毒活疫苗(Oral Poliomylitis Attenuated Live Vaccine,OPV)免疫覆盖率情况,推测在当地存在1例免疫缺陷患者,由他/她长期携带并向外排泄变异的脊灰病毒,引起了山西省2007年VDPV感染事件。在脊灰消灭后期,应加强对可能存在的长期排毒者的发现和管理。
Objective To describe the source of vaccine-derived poliovirus （VDPV） and the effect on local polio-free status, the VP1 coding region was sequenced and analyzed for type Ⅰ VDPV in Shanxi province in 2007. Method The virus isolation was performed to double stool specimens from one case acute flaccid paralysis （AFP） patient. VP1 coding region of the isolated stain was sequenced and analyzed. The phylogenetic tree was constructed based on VP1 region sequence between Shanxi strains and other type Ⅰ VDPVs. Result 2 type Ⅰ ＋ Ⅱ ＋Ⅲ strains were isolated from double stool specimens from the AFP patient in Shanxi Province in 2007. VP1 sequencing of the two stains revealed 〉1.0% divergence from the VP1 region of P I/Sabin vaccine strain. According to WHO criteria, the two stains were identified as type Ⅰ vaccine-derived poliovirus （VDPV）. Phylogenetic analysis based on VP1 coding sequence showed that the evolution distance of Shanxi type Ⅰ VDPV was far away from other VDPVs detected in China. Moreover, no evidence supported the AFP patient as immunodeficiency patient. So Shanxi type Ⅰ VDPVs were classified into ambiguous VDPV（aVDPV）. Conclusion Considering the genetic character for Shanxi type Ⅰ VDPV and the local OPV coverage, we highly suspected that an immunodeficiency patient in local area who long-term excreted VDPVs existed and resulted in the patient infection of VDPV in Shanxi in 2007. In the post era of polio eradication, the detection and management for the possible existing patient of long-term excretion VDPV should be strengthened.
出处
《中国疫苗和免疫》
CAS
2009年第2期131-134,共4页
Chinese Journal of Vaccines and Immunization
基金
卫生部2007年疾病预防控制专项基金
