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中国云南省昭通地区从 1 997年以来每年都是急性弛缓性麻痹 (Acuteflaccidparalysis,AFP)病例的高发地区 ,该地区的镇雄县 1 997～ 2 0 0 1年每年都有≥ 2例由Ⅱ型脊髓灰质炎 (脊灰 )疫苗相关株引起的AFP病例。日本国际协力事业团 (JICA)中国消灭脊灰项目的临床专家曾于 2 0 0 1年赴当地核查这些AFP病例 ,最终临床确认了 4例脊灰 ,认为存在脊灰病例聚集现象。针对此情况 ,对云南省镇雄县 1 997～ 2 0 0 1年从AFP病例中分离到的Ⅱ型脊灰毒株 (共 1 3株 )进行了序列分析 ,发现其VP1和 3D区核苷酸序列变化位点、变化数目及改变各不相同 ,其中有 8株为S2×S3重组株 ,5株为S2×S2疫苗相关株。病毒基因的分析不支持聚集病例间毒株的传播关系 ,不存在单一毒株循环引起的聚集现象。发现其中 1株为脊灰疫苗衍生病毒 (VDPV) ,但未发现其自然循环引发疾病流行。
Zhaotong, Yunnan Province, China is an area with high incidence of acute flaccid paralysis (AFP) every year since 1997. From 1999 to 2001, Zhenxiong County in this area annually has ≥2 cases of type A Poliovirus (polio) vaccine-related strains caused by AFP cases. Clinical experts from Japan International Cooperation Agency (JICA) China Polio Eradication Project went to Hong Kong to verify these AFP cases locally in 2001, and finally confirmed the poliovirus in 4 cases and concluded that polio cases are accumulating. In view of this situation, we have sequenced the type II poliovirus strains (13 strains) isolated from AFP from 1999 to 2001 in Zhenxiong County, Yunnan Province and found that VP1 and 3D nucleosides The number of acid sequence changes and the number of changes were different. Among them, 8 were S2 × S3 recombinant strains and 5 were S2 × S2 vaccine-associated strains. Analysis of the viral genes does not support the spread of the strains in the aggregate cases, and there is no aggregation caused by a single strain cycle. One of them was found to be a polio vaccine-derived virus (VDPV), but no natural circulation was found to trigger the disease.