腺病毒3型引起的儿童咽结膜炎暴发

Outbreak of Pharyngoconjuctivitis Caused by Adenoviruses Type 3 in Shenzhen

目的 分析腺病毒3型引起的咽结膜炎暴发的流行病学特征。方法 对幼儿园发生的咽结膜炎暴发病例进行发病经过和传播因素调查,采集眼、咽拭子进行病毒分离和鉴定,并检测双份血清抗体。结果 病例主要发生在幼儿园2个小班,罹患率分别为71.8％和89.7％,流行曲线呈现2个高峰,共持续17天,由幼儿间密切接触经呼吸道传播。患儿龄4～5岁,高热39℃以上占90.0％,持续高热3天以上占87.9％;眼结膜充血占57.6％,伴流涕、咽痛等症状者占69.7％;推测最短潜伏期为1～4天。经Hep-2细胞培养分离到病毒19株,采用中和试验鉴定为Ad3,与PCR检测结果一致。用标准Ad3和自身分离到的毒株对24例患儿双份血清进行检测,抗体滴度呈4倍升高;进一步对毒株进行限制性内切酶分析,符合Ad3a2图谱特征。结论 疫情是由腺病毒3型引起的咽结膜炎暴发。

ve To analyse the epidemiologic features of an outbreak of pharyngoconjuctivitis caused by adenoviruses type 3 ( Ad3 ) . Methods All cases in the outbreak were investigated for the process of illness, symptoms and infection factors. The viruses were cultured in Hep - 2 cells and isolated from eye and pharynx swabs of the patients with pharyngoconjuctivitis and the viruses types were determined using restriction endonuclease analysis(REA) .The neutralizing antibodies to the Ad3 in the paired sera were detected. Results The outbreak occurred among the children aged 4-5 years in a kindergarten in Shenzhen. The cases were concentrated in two classes and the attack rates were 71.8% (28/39) and 89.7% (35/39) respectively . Most of the cases displayed symptoms of the illness, with the proportion of 90. 0 % being high fever( > 39℃), 57.6 % with the conjuctivitis, and 69.7% with sore throat and other symptoms in upper respiratory tract. Total of 19 strains isolated from the swabs had an identical genotype, Ad3. The virus DNA by PCR was detected and 3 strains proved belonging to Ad3a2 by the REA. Twenty four cases showed that the neutralizing antibody titers had 4 fold rising or above. The source of infection was followed up and the route of transmission was speculated to contact among the children and by respiratory tract.Conclusion The outbreak of pharyngoconjuctivitis was caused by adenovirus type 3.