摘要
我国自 1994年 10月以后已无脊髓灰质炎 (脊灰 )本土野病毒引起的病例。现在从急性弛缓性麻痹病例粪便标本中分离到的脊灰病毒都是 3个血清型的疫苗衍生株 ,并以Ⅱ型为主。近几年每年Ⅱ型分离株的数量均多于同年Ⅰ型株加Ⅲ型株之和。 1997～ 1999年从贵州、云南省分离到的Ⅱ型疫苗株中 ,除了疫苗变异株外 ,还发现了不同血清型间的重组株 ,如VP1片段来自SabinⅡ ,而 3D片段分别来自SabinⅢ (S2 ×S3 )和SabinⅠ (S2 ×S1) ,它们的基因序列与脊灰疫苗株SabinⅡ型有差异。能从未服苗儿童的粪便标本中分离到这类毒株 ,表明在外环境中有这类毒株在循环。这些毒株可以致病 ,其致病性与该儿童是否接受了疫苗全程免疫有很大的相关性。重组株的发现提示我们 ,它们在自然环境中已有循环。从贵州省Ⅱ型病例发生时间和区域上看 ,病例有聚集分布的趋势 ,但目前尚处于小范围的循环中 ,其原因与对策有待进一步研究。
Since Oct1994,there was no poliomyelitis case caused by indigenous wild poliovirus in ChinaIn the meantime,type Ⅱ Sabin vaccine-derived poliovirus isolated from the acute flaccid paralysis(AFP) cases increased,the amount was more than the sum of Sabin Ⅰ and Sabin Ⅲ. Many Sabin Ⅱ vaccine-derived polioviruses were recombinant strains, which have Sabin Ⅱ like fragment in VP 1 coding region and Sabin Ⅲ like fragment in 3D coding region (S 2×S 3)This kind of recombinant virus was circulating in China and, as a pathogen,caused acute flaccid paralysis From 1997-1999,a total of 163 Sabin vaccine viruses were isolated in two neighbor provinces Guizhou and Yunnan Provinces locating in the southwest of China Of the 163 Sabin vaccine viruses,93 viruses were type Ⅱ and 75 of the 93 type Ⅱ caused AFP cases had OPV dose records,but among them 28 had “0” dose This means that these type Ⅱ viruses came from the environment and, as a pathogen, could cause the diseaseThe residual paralysis of AFP happened more likely among children with“0” dose of OPV than children with 3 or more than 3 dosages,their residual paralysis rate were 70% and 375% respectively The way of spreading of the S 2×S 3 recombinant polio virus was estimated in Guizhou (1997) according to the order of onset data of AFP cases,it clearly showed the recombinant strain(S 2×S 3) was circulating in the province
出处
《中国计划免疫》
2001年第3期125-128,共4页
Chinese Journal of Vaccines and Immunization
基金
国家自然科学基金部分资助! (3 9770 0 3 9)
关键词
脊髓灰质炎病毒
疫苗衍生株
重组株
全程计划免疫
Poliovirus
Vaccine-derived strain
Recombinant strain
Full-course immunization
