中国急性弛缓性麻痹病例中脊髓灰质炎病毒分离优势型别株的性状分析  

The Analysis of the Dominant Poliovirus Strains Isolated from AFP Cases in China

作　　者：侯晓辉[1] 张礼璧[1] 祝双利[1] 陈立[1] 张勇[1] 李杰[1] 

机构地区：[1]中国疾病预防控制中心病毒病预防控制所,北京100050

出　　处：《中国计划免疫》2003年第4期193-195,共3页Chinese Journal of Vaccines and Immunization

摘　　要：中国自 1994年 10月以后 ,成功地阻断了脊髓灰质炎 (脊灰 )野病毒在自然环境中的传播 ,虽然云南、青海两省发现过由境外输入的脊灰野病毒病例或输入的脊灰野病毒引起的病例 ,但并未出现由此引发的第二代病例。与此同时 ,全国对每年 5 0 0 0多例急性弛缓性麻痹 (AFP)病例的病毒学监测发现 ,脊灰Ⅱ型疫苗病毒株的分离数逐年增加 ,1994年Ⅱ型株第一次超过了Ⅰ型或Ⅲ型株 ,1997年以来 (除 2 0 0 0年外 )Ⅱ型株多于Ⅰ型加Ⅲ型株之和。同时在病毒基因编码区VP1和 3D区的分析表明 ,中国Ⅱ型病毒株有接近半数均为在 3D基因编码区与不同型别的疫苗重组脊灰病毒 (VRPV)。VRPV ,特别是Ⅱ型VRPV ,除个别北方省份外 ,在全国大部分地区均有发现。序列分析表明 ,除在江苏、贵州、云南省发现过疫苗衍生脊灰病毒 (VDPV)外 ,大部分病毒在基因序列VP1段与脊灰疫苗参考株的差异率均 <1% ,表明VDPV虽然在中国有过局限性的循环 ,但并非优势型别株。占优势的是Ⅱ型VR PV ,这一类病毒是否能引起脊灰流行是共同关切的问题。该文就中国Ⅱ型VRPV的性状做了分析 ,并探讨了其发展趋势。After being one of the polio-free regions,China reported more than 5000 AFP cases each year.The poloviruses isolated from these cases reached a stable number of 300 to 400 in recent years and the serotype Ⅱ poliovirus gradually increased in proportion to serotype Ⅰ and Ⅲ.Before the year of 1994,the dominant poliovirus strains were serotype Ⅰ but it shifted to serotype 2 after that year.Since the year of 1997(except 2000),the number of serotype 2 poliovirus even exceeded the sum of type Ⅰ and Ⅲ.We randomly selected the atypical Sabin-like strains which showed a different polymorphism in one or two restriction enzyme patterns in the assay of PCR-RFLP and found that most of them have a homology of more than 99 percent compared to their Sabin references at the VP1 coding genomic fragment.Only four isolates from Jiangsu in 1996 and 1998,two from Yunnan in 1997 and one from Guizhou in 1997 slightly exceeded one percent nucleotide divergence in the same fragment.According to the WHO definition that strains with divergence in VP1 region more than 1 percent but less than 15 percent should be regarded as the vaccine derived polioviruses(VDPV),therefore most of the domestic isolates are not VDPVs but Sabin-like strains.On the other hand,more than 47 percent of the serotype 2 strains in the years of 2000 are vaccine-recombinant polioviruses(VRPVs).These recombinant viruses,in their 3D region,have a sequence of serotype 1 or 2 of the Sabin references.The VRPV is the dominant strain in China instead of the VDPV.

关 键 词：中国 急性弛缓性麻痹病 脊髓灰质炎病毒 分离优势型别株 性状分析 

分 类 号：R512.4[医药卫生—内科学]