疫苗接种对北京市托幼园所和中小学校水痘流行特征的影响

目的 了解疫苗接种对北京市托幼园所、中小学校水痘流行特征的影响.方法 通过国家疾病监测信息报告管理系统追踪北京市托幼园所、中小学校2008-2010年发病的临床诊断水痘病例,开展流行病学个案调查,分析分布特征.结果 共调查水痘病例21 474例,其中:55.3％(11 883例)的病例接种过水痘疫苗；有明确免疫史的病例中,接种时间距离发病时间在30 d～1年的占3.4％(286/8510)、1～3年的占18.2％(1551/8510)、3～5年的占28.6％(2431/8510)、5～10年的占34.3％(2916/8510)(时间区间均为左闭右开)；无免疫史的病例发病年龄高峰为4岁,有免疫史的病例发病年龄高峰为6岁；有免疫史(≥30 d)病例的比率由2008年的42.4％(2862/6754)上升到2010年的56.3％(4327/7679);未发热病例有免疫史(≥30 d)的比率(54.9％,6413/11 679)高于发热病例(47.7％,4533/9500)(P ＜0.01)；轻症病例中有免疫史(≥30 d)的比率(57.4％,8045/14 020)高于中重度病例(40.2％,2902/7216)(P＜0.01).结论 疫苗接种推迟了水痘发病高峰,减轻了疾病症状,但既有免疫策略无法阻断水痘在托幼园所、中小学校内的传播.

The epidemiological impact of varicella vaccination in kindergartens, primary and secondary schools in Bering

Objective To study the epidemiological impact of varicella vaccine vaccination on kindergartens and school children in Beijing.Methods According to " China Information System for Diseases Control and Prevention",the reported clinical diagnosis varicella cases were tracked in kindergartens,primary and secondary schools whose onset date were from 2008 to 2010.Epidemiological survey was conducted and epidemiological features were analyzed.Results A total of 21 474 varicella cases were investigated: 55.3％ (11 883 cases) had been vaccinated by varicella vaccine.Of cases with definite immunization history,interval between vaccination date and onset date were from 30 days to 1 year accounted for 3.4％ (286/8510),1 to 3 years accounted for 18.2％ (1551/8510),3 to 5 years accounted for 28.6％(2431/8510),5 to 10 years accounted for 34.3％ (2916/8510) ( left-closed right-open interval) ; The peak age of onset was 4 years old in cases without immunization history,which was 6 years old in cases with immunization history; The proportion of cases with immunization history ( ≥ 30 days) had increased from 42.4％ (2862/6754) in 2008 to 56.3％ (4327/7679) in 2010.The cases with no fever had a higher proportion (54.9％,6413/11 679 ) of immunization history ( ≥ 30 days) than cases with fever (47.7％,4533/9500) (P＜ 0.01 ); The cases with rashes less than 50 had a higher proportion (57.4％,8045/14 020) of immunization history ( ≥ 30 days) than cases with rashes more than 50 (40.2％,2902/7216) (P ＜ 0.01 ).Conclusion Varicella vaccine delays the peak age of onset,alleviates the symptoms.The current immunization strategy can not block varicella spread in kindergartens,primary and secondary schools.