一起由腺病毒3型引起的儿童咽结合膜热暴发

An Outbreak of Children Pharyngo-conjuctival Fever Induced by Type III Adenovirus

目的分析腺病毒3型引起的咽结合膜热暴发流行病学特征和流行因素。方法通过描述性流行病学分析方法和病例对照的研究方法,对幼儿园发生的咽结合膜热暴发病例进行发病经过和传播因素的调查,采集患者咽拭子进行病毒分离,核酸鉴定,采集血清进行病毒抗体检测。结果自2004年6月21日～7月19日,幼儿园349名幼儿中共有258人发病,罹患率73.9%。病例分布在不同年级、班别间无差别。流行曲线呈单峰型。在日托幼儿中,参加游泳幼儿的罹患率明显高于未参加游泳的幼儿(X2=28.96,P<0.001),且随游泳次数的增多,罹患率升高。实验室结果,用PCR检测27例病人的咽拭子标本,10份腺病毒基因阳性(37.0%),其中6份进行了基因序列测定,并对获得的基因序列(290bp)进行分析,显示与腺病毒3型同源性达97%,可认为PCR扩增物为3型腺病毒。同时还检出呼吸道合胞病毒、I型副流感病毒等其它病原体。结论此次疫情主要的病原体是腺病毒3型,幼儿主要通过在幼儿园游泳池戏水以及接触传播的途径引起咽结合膜热暴发,同时合并其它多种病原体感染。

Objective This essay was to analyze the epidemiological features and epidemic factors in outburst of pharyngo-conjunctival fever resulted from type III adenovirus. Methods Descriptive epidemiological analysis and case control study were adopted to investigate the course of onsets and transmission factors of pharygno-conjunctival fever taking place in kindergartens, accompanied by nucleic acid identification of isolated virus using throat swabs and determination of antibodies against virus by collecting serum. Results From 21st of June to 19th of July in 2004, 258 of 349 young children in kindergartens fell ill, with an attack rate of 73.9%. The cases were distributed among different grades while had no significant difference between classes. The epidemiological curve took on a single peak. Among children under day-care service, the attack rate of children who participated in swimming sports was obviously higher than those who did not (X 2=28.96,P<0.001) and increased along with the frequency of swimming. Experimental results indicated that 10 pharnyx swabs of 27 patients were determined as adenovirus positive by PCR (37%), for 6 of which genetic sequencing was applied besides analysis of genetic sequence (290bp) acquired, demonstrating a homology of 97% with ?type ? III? adenovirus? so that the amplification product of PCR can be regarded as type III adenovirus. In the meanwhile, other pathogens such as respiratory syncytial virus and type I parainfluenza virus were also detected. Conclusion The principal pathogen of this epidemic is type III adenovirus, and pharyngo瞔onjunctival fever breaks out mainly through water and contact transmission when young children are playing in the swimming pool of kindergartens, combining with many other pathogenic infections.