一起腺病毒感染暴发疫情分子流行特征分析

Molecular epidemic characteristics analysis of an adenovirus infection outbreak

目的了解2012年辽宁省某中学暴发的一起腺病毒感染的分子流行特征。方法收集患病学生个案资料,采用多重聚合酶链反应(PCR)从咽拭子标本中进行腺病毒鉴定并进行病毒分离,扩增腺病毒六邻体(Hexon)基因的L1片段进行序列测定,BLAST比较并构建系统发生树。结果 1个月内在3个班级78名学生中累计出现24例发热病例,发病率为30.77%;咽拭子标本中5份标本多重PCR鉴定为腺病毒,同时分离到5株病毒;腺病毒Hexon基因的L1片段测序显示5株腺病毒之间的核苷酸序列100%相同;BLAST比较显示与人腺病毒14型参考株高度同源,达100%;系统进化分析中5株腺病毒与人腺病毒14型参考株位于同一进化分支。结论本次暴发疫情是由腺病毒14型引起,与之前中国所流行的腺病毒14型相比未发生基因变异。

Objective To examine molecular epidemic characteristics of an adenovirus infection outbreak in a middle school in Liaoning province in 2012. Methods Data of the cases of the infection outbreak were collected. Throat swabs were tested with multiple polymerase chain reaction （PCR）for adenovirus identification and the viruses were isolated simultaneously. L1 of Hexon gene in adenovirus genome was sequenced and blasted. Phylogenetic tree of L1 of Hexon was constructed with neighbor-joining method by using Mega 5.1 software. Results Totally 24 students with fever were found in 3 classes during a month. The incidence of the disease between boys and girls was not different, but the incidences among classes were different. Five throat swabs were positive for adenovirus and 5 isolates were isolated at the same time from the same throat swabs of the patients. The nucleotide identities of the 5 isolates were 100% and basic local alignment search tool（BLAST） analysis showed that 5 isolates were 100% homology with adenovirus 14. The 5 adenovirus were in the same branch with other adenovirus 14 in the phylogenetic tree. Conclusion The pathogen of this outbreak was adenovirus 14 and the virus was not mutated compared with the adenovirus 14 prevalent before in China.