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2007年北京市发生了急性出血性结膜炎(Acute Hemorrhagic Conjunctivitis,AHC)疫情。为鉴定引起这次疫情的致病病原体,采集北京市门诊就诊的AHC患者眼结膜拭子标本共57份,使用PCR或RT-PCR法分别检测临床标本中腺病毒、人肠道病毒70型(Human Enterovirus 70,HEV70)和柯萨奇病毒A组24型变种(CoxsackievirusA24 variant,CVA24v)的基因,其中有38份检测结果为CVA24v阳性,阳性率为66.7%,而腺病毒和HEV70检测结果均为阴性,说明引起本次AHC流行的病原体是CVA24v。使用HEp-2细胞共分离到9株病毒,通过分子定型均鉴定为CVA24v,对9株CVA24v进行全长VP1区扩增和核苷酸序列测定和分析后,发现除0744/BJ/CHN/2007株之外,其它8株在全长VP1区核苷酸水平和氨基酸水平上差异都很小,同源性分别大于99.6%和100.0%,而0744/BJ/CHN/2007株与其它8株CVA24v的核苷酸和氨基酸同源性分别为96.8%~97.2%和99.7%。进化树图显示,2007年北京CVA24v分离株与基因群I中的代表株聚为一簇,代表了基因群I中的第四和第五进化分支,说明本次流行至少存在两个传播链。相对于CVA24v的3C区而言,VP1区是进行分子流行病学研究的更为严谨的靶序列,加强对CVA24v的血清流行病学和分子流行病学监测和研究,了解CVA24v的基因特征和分子进化,对预防和控制CVA24v在中国的流行具有重要意义。
In 2007, an outbreak of acute hemorrhagic conjunctivitis (AHC) occurred in Beijing. In order to identify the causative pathogens causing this outbreak, we collected 57 conjunctival swab specimens of AHC patients from outpatient clinics in Beijing. PCR and RT-PCR were used to detect adenovirus and human enterovirus 70 Human Enterovirus 70, HEV70) and Coxsackievirus A24 variant (CVA24v), of which 38 were positive for CVA24v, the positive rate was 66.7%, while the results of adenovirus and HEV70 were Negative, indicating that the cause of this AHC epidemic is CVA24v. Nine strains of HEV-2 cells were co-isolated and identified as CVA24v by molecular typing. After amplifying and sequencing the full-length VP1 region of nine strains of CVA24v and analyzing the nucleotide sequence, it was found that in addition to 0744 / BJ / CHN / 2007 The other 8 isolates had small differences in the nucleotide and amino acid levels of the full-length VP1 region with homologies of 99.6% and 100.0%, respectively, while the other strains of 0744 / BJ / CHN / 2007 and the other 8 strains of CVA24v The nucleotide and amino acid homologies were 96.8% ~ 97.2% and 99.7%, respectively. Phylogenetic tree shows that in 2007 Beijing CVA24v isolates were clustered with the representative strains in gene group I, representing the fourth and fifth evolutionary branches in gene group I, indicating that there are at least two transmission chains in this epidemic. Compared with the 3C region of CVA24v, the VP1 region is a more rigorous target sequence for molecular epidemiological studies, which enhances the surveillance and study of serum epidemiology and molecular epidemiology of CVA24v and the genetic characteristics and molecules of CVA24v Evolution, the prevention and control of CVA24v epidemic in China is of great significance.