安徽省六安市一起埃可病毒6型脑膜炎暴发的调查

目的分析2005年安徽省六安市一起埃可病毒6型（Ech06）脑膜炎暴发疫情的流行病学、临床、实验室特征。方法对所有病例进行流行病学、临床特征分析，通过病例对照调查危险因素。采用病毒分离方法确定病原，运用分子生物学检测进一步确证，利用血清学检测分析隐性感染情况。结果105例病例分布在金寨县30个乡镇中的17个，41．0％病例集中在斑竹园镇，该镇罹病率为203／10万，具有学校和班级聚集性。发病年龄在3～15岁之间，以6～10岁小学生为主，平均年龄7．8岁，罹病率为10．9／10万，男性和女性的罹病率分别为24．2／10万和8．4／10万。大部分患者主要临床表现为发热、头痛、呕吐。从72例患者脑脊液中分离出25份Ech06，占35％。病例组与对照组比较，喝饮料OR=4．1，95％CI：1．4～12．0；尤其喝袋装饮料OR=3．3，95％CI：1．3～8．8。在生产袋装饮料的7名职工中有6人粪便检出Ech06。100名7～14岁健康人血清中和抗体阳性46人，阳性率46．0％，与病例组阳性率73．5％相比差异有统计学意义（Χ^2=12．526，P=0．000）。结论为一起主要由Ech06感染所致的病毒性脑膜炎的疫情，病例组喝饮料尤其袋装饮料的比例明显高于对照组。

Study on an outbreak of Echovirus type 6 of meningitis in Liu''an city, Anhui province

OBJECTIVE: To understand the epidemiological, clinical and etiological characteristics of an Echovirus type 6 meningitis outbreak in Jinzhai county, Liu'an city in Anhui, and to find out the proper way in controlling the aseptic meningitis outbreak. METHODS: A surveillance system for aseptic meningitis was established in Jinzhai to confirm the case definition. Stool or cerebrospinal fluid (CSF) specimens from some cases were collected for entero-viruses isolation and identification. Case-control study was conducted. The case group involved patients while the controls would include: patients' classmate with same gender and the age difference was not over one year. Neutralization antibody in serum specimens were collected and tested in cases and in healthy people. RESULTS: 105 cases were distributed in 17 of the 30 towns in Jinzhai county while 41.0% of the cases were in Banzhuyuan town with an incidence rate of 203/10(5). Cases were clustered by school and classroom with age ranging from 3 to 15 years old and the highest as 10.9/10(5) in the 6 to 10 group. The incidence in males was 24.2/10(5) compared to 8.4/10(5) in females. The main clinic characteristics of cases were: fever, headache and vomiting. Echovirus type 6 from 25 of the 72 CSF samples (35%) was isolated. When comparing the cases group with control group, the OR of drinking home-made beverages was 4.1 (95% CI: 1.4-12.0), especially the beverages sacked by plastic bag: 3.3 (95% CI: 1.3-8.8). 6 out of 7 workers engaging in producing home-made beverages were detected to have carried Echovirus type 6 from their stool specimens. The Echovirus type 6 neutralization antibody positive rate in cases (73.5%) was significantly higher than that in 100 healthy people (46.0%) (X2 = 12. 526, P = 0.000). CONCLUSION: This episode of meningitis outbreak was caused by Echovirus type 6. The proportion of drinking home-made beverages, especially the beverages sacked by plastic bag in cases group was higher than in control group.