北京市2008年肠道病毒71型的RT-PCR鉴定及VP1区基因特征分析

RT-PCR identification and genetic characterizations of VP1 region of human enterovirus 71 isolated in Beijing in 2008

目的 研究2008年北京市手足口病（Hand,foot and mouth disease,HFMD）患者中肠道病毒71型（Human enterovirus 71,HEV71）的VP1编码区基因特征.方法 采集北京市朝阳区医院和幼儿园的HFMD患者标本共285份,进行HEV71特异性RT-PCR鉴定和病毒分离,随机选取10株HEV71阳性分离株进行VP1编码区基因扩增和核苷酸序列测定和分析.结果 129份标本RT-PCR鉴定结果 为阳性,阳性率为45.26%.10株HEV71在VP1区核苷酸水平和氨基酸水平上的差异分别在94.6%～99.6%和95.9%～100%之间.北京朝阳HEV71分离株属于C4基因亚型C4a进化分支.结论 RT-PCR法可以快速、准确地鉴定HEV71.引起本次HFMD流行的HEV71为C4基因亚型C4a进化分支,并且存在多个传播链,提示自1998年起,C4亚型的HEV71在中国大陆有较广泛的传播.加强对HEV71的分子流行病学监测,了解HEV71的基因特征,对预防和控制HEV71在中国的暴发具有重要意义.

Objective To study the genetic characterizations of VP1 region of Human enterovirus 71 （ HEV71 ） isolated from clinical specimens of hand, foot and mouth disease （HFMD） patients in Beijing in 2008. Methods 285 clinical samples were collected from HFMD patients in hospitals and day-care centers in Chaoyang district. They were performed by reverse transcription-polymerase chain reaction （ RT-PCR ）specific for HEV71. 10 HEV71 isolates were selected for entire VP1 coding gene amplification and sequencing. Results 129 samples were RT-PCR positive, the positive rate is 45.26%. The homology of the nucleotide and the amino acid of the 10 strains were 94.6%-99. 6% and 95.9%-100%. The phylogenetic tree revealed that 10 Beijing strains clustered within the C4a evolution branch of C4 subgenotype. Conclusions RT-PCR played an important role in identifying HFMD outbreak in Beijing in 2008. The HEV71 strains were all belong to C4a evolution branch of C4 subgenotype with several transmission chains, and it showed that C4 subgenotype HEV71 spread in China's Mainland widely after 1998.The molecular epidemiology surveillance and the research of genetic characterizations of HEV71 should be strengthened in China's Mainland.