玉溪市一起人腺病毒感染导致的儿童呼吸道感染暴发疫情调查

Investigation of an outbreak of respiratory tract infection caused by adenovirus in children in Yuxi City

目的了解云南省玉溪市一起儿童呼吸道感染暴发疫情的流行病学及病原学特征。方法对此次暴发进行现场调查,对病例发病过程及流行病学特征进行描述性研究。采集与此次暴发有流行病学相关的住院病例咽拭子样本,采用实时荧光PCR方法对样本进行腺病毒核酸检测,并对腺病毒核酸阳性样本进行病毒分离培养,对分离株进行六邻体基因扩增、测序。结果此次疫情历时11 d,共出现58例住院患儿,临床症状以发热、畏寒和扁桃体发炎为主,在发病前7 d内有某游泳馆暴露史。所采集的20份咽拭子样本腺病毒核酸检测均为阳性,分离培养得到13株腺病毒毒株。六邻体基因测序得出所测13株腺病毒序列相同,基因进化树显示这批分离株均为腺病毒B群,与人腺病毒7型参考株处于同一分支,同源性为100.00%。结论此次疫情有明显的聚集性和儿童易感性,引起疫情的病原为腺病毒7型。

Objective To investigate the epidemiological and pathogenic characteristics of an outbreak of respiratory tract infection in children in Yuxi,Yunnan.Methods The outbreak in Yuxi City was investigated to analyze the process of disease and epidemiological characteristics.Throat swab samples of hospitalized cases related to the outbreak were collected and tested by real-time PCR for adenovirus.The positive adenovirus specimens were used for viral isolation.The hexon regions of the isolated strains were amplified and sequenced.Results The epidemic lasted 11 days with a total of 58 hospitalized children.The main clinical symptoms were fever,chills,tonsil inflammation.All the cases exposed to the same swimming pool within 7 days before the onset.A total of 20 throat swab specimens were positive for respiratory adenovirus,and 13 adenovirus strains were isolated and cultured.The hexon gene sequencing showed the same sequence among 13 adenovirus strains,which were all adenovirus B subsets by phylogenetic tree and were homologous to those of human adenovirus type 7 with 100.00%similarity.Conclusions This outbreak has an obvious aggregation and susceptibility in children,and the pathogen is adenovirus type 7.