2009-2011年河北省脊髓灰质炎疫苗病毒核苷酸变异情况分析

Nucleotide Variation of Poliovirus Isolated From Acute Flaccid Paralysis Cases in Hebei Province,2009-2011

目的分析河北省2009-2011年急性弛缓性麻痹(AFP)病例及其密切接触者中脊髓灰质炎(脊灰)病毒分离株VP1编码区基因核苷酸变异情况,及时发现可能出现的疫苗衍生脊灰病毒(Vaccine-derived poliovrus,VDPV)及其引起的VDPV循环(Circulating VDPV,cVDPVs),为河北省维持无脊灰状态提供依据。方法按照《世界卫生组织(WHO)脊灰实验室手册》的要求,对全省2009-2011年997例AFP病例及90例的接触者的粪便标本进行病毒分离与鉴定,分离的脊灰病毒送中国疾病预防控制中心(CDC)病毒病预防控制所国家脊灰实验室进行VP1编码区基因核苷酸序列测定与分析。结果河北省2009-2011年,从24例AFP病例和7例AFP病例的密切接触者粪便标本中分离到脊灰病毒,将混合株进行单型分离,得到38株脊灰病毒,经国家脊灰实验室对脊灰病毒VP1编码区基因核苷酸序列测定,其中,36株发生突变,变异率均<1.0%,最多变异个数为5个。脊灰病毒阳性AFP病例男性明显高于女性,主要集中在小年龄组。结论2009-2011年分离到的脊灰病毒均为疫苗株,局部地区出现高变异株,未发现VDPV,河北省继续保持无脊灰状态。

Objective To analysis the VP 1 nucleotide variation of poliovirus isolated from acute flaccid paralysis （ AFP ） cases and close contacts in Hebei province during 2009 - 2011, so as to detect vaccine - derived polio- vires （VDPV） and Circulating VDPV （VDPVs） timely and provide the evidence for maintaining polio free sta- tus. Method All stool samples from acute flaccid paralysis （AFP） cases and close contacts were vitally isolated and identified according to the World Health Organization （WHO） Polio Laboratory Manual and then performed VP1 sequencing. Results During 2009 - 2011,24 cases AFP cases and 7 cases of AFP close contact were iso- lated with poliovims. After single type isolation from the mixed, 38 single type were obtained, and 36 strains of which occurred mutation with VP1 gene nucleotide, with a mutation rate under 10%. Poliovirus positive cases were higher in males than that in females and mainly in low age groups. Conclusion During 2009 to 2011, the polioviruses were all vaccine strains. The high variability of the virus appeared in local areas; vaccine derivedpolio virus case were not found. Hebei province continues to maintain the polio- free status.