中国疫苗和免疫

目的分析中国(未包括香港、澳门特别行政区和台湾地区,下同)2012~2013年麻疹流行病学特征和消除麻疹的策略与措施,为消除麻疹提供参考。方法对中国2012~2013年麻疹发病、麻疹监测系统(Measles Surveillance System,MSS)运转指标,以及采取的消除麻疹策略与措施进行描述流行病学分析。结果中国2012年报告麻疹发病率为0.46/10万(6183例),报告死亡8例;2013年报告麻疹发病率为2.04/10万(27 646例),报告死亡24例。2013年报告发病率、病例数、死亡数分别较2012年增加343.48%、347.13%、200.00%。2012年未出现3⁵月的麻疹发病季节高峰,但2013年较为明显。2012年和2013年,青海、广东省和新疆维吾尔自治区报告发病率均居全国前5位,2012年全国有1074个县(区、市、旗,下同)、2013年有1871个县有麻疹病例报告。两年均以<8月婴儿麻疹发病率最高,其后依次为8~23月龄、2⁶岁、15~34岁、7~14岁、≥35岁。2012年<8月龄、8~23月龄、2⁶岁、7~14岁、≥15岁麻疹病例分别占24.47%、33.92%、11.95%、2.41%、27.25%,2013年分别占30.81%、29.59%、10.34%、2.29%、26.97%。两年8~23月龄麻疹病例无含麻疹成分疫苗(Measles-containing Vaccine,MCV)免疫史的均>70%,2³岁麻疹病例中约50%无MCV免疫史。2012~2013年MSS各项运转指标中,排除麻疹病例报告发病率均>2/10万,疑似麻疹病例48h内完整调查率、散发疑似麻疹病例血标本采集率、血清学检测结果 7d内报告率均>97%,麻疹爆发疫情病原学标本采集率<80%。2012~2013年共报告了2009例麻疹病例基因型鉴定结果,H1a基因亚型所占比例均>96%。结论中国消除麻疹虽然取得了明显进展,但仍存在薄弱地区、薄弱人群,经过近年易感者的积累,麻疹疫情开始反弹。需要扎实地落实既定的消除麻疹策略与措施,包括以提高适龄儿童MCV及时、全程接种率为核心,重点地区必要时开展选择性或非选择性MCV补充免疫活动,加强麻疹监测,提高MSS敏感性,做好麻疹疫情调查与处置,并关注小月龄婴儿和成人易感者在麻疹病毒传播中的作用、探讨针对性的策略与措施。

Objective To analyze the epidemiological characteristics and summarize progress towards measles elimination in China( exclude Hong Kong and Macao Special Administrative Region,and Taiwan Sheng) during 2012- 2013,and to provide evidence for making strategies and measures for measles elimination. Methods Data from the National Measles Surveillance System( MSS) were analyzed by descriptive epidemiology,and the strategies and measures taken for measles elimination during 2012- 2013 were described. Results The reported number of measles cases was 6,183( including 8 deaths) in 2012,representing an incidence of 0. 46 per 100,000 population. The reported incidence,number of measles cases,and deaths were 2. 04 per 100,000 population,27,646 cases,and 24 deaths in 2013,which were increases of 343. 48%,347. 13%,and 200. 00% compared with 2012,respectively. The usual seasonal peak incidence of measles in April and May was low in2012 but occurred again in 2013. Higher incidence rates were reported in Qinghai and Guangdong provinces,and Xinjiang Uygur Autonomous Region in 2012 and in 2013. There were 1,074 counties in 2012,and 1,871 counties in 2013 with ≥1 cases reported. In 2012 and again in 2013,the highest measles incidence rates were among children aged < 8months,followed by 8- 23 months,2- 6 years,15- 35 years,7- 14 years,and ≥35 years. The percentages of measles cases in these age groups,respectively,were 24. 47%,33. 92%,11. 95%,2. 41%,27. 25% in 2012,and were 30. 81%,29. 59%,10. 34%,2. 29%,26. 97% in 2013. During 2012- 2013,over 70% of 8- 23 months old cases and over 50% of 2- 3 years old cases had no history of receiving measles- containing vaccine( MCV). There were > 2 non-measles cases reported per 100,000 population,and each of the following MSS indicators were above 97% during 2012 and 2013: proportion of suspected measles cases investigated within 48 hours of report,proportion of suspected cases with adequate serum specimens,percentage of serum specimen results reported within 7 days of collection. However,< 80% of measles outbreaks had specimens collected for virus detection. Among the 62 measles outbreaks,98. 39% were laboratory-confirmed,and 75. 81% of the 2009 measles cases had measles virus isolated,and among those,> 96% were identified as H1 agenotype. Conclusions Although substantial progress toward measles elimination has been made,weak areas and high risk populations exist in some areas that allow rapid accumulation of susceptibles and sustained measles virus transmission. Additional efforts are needed for the implementation of current measles elimination strategy,including timely administration of 2 doses of MCV doses at 8 months and 18 months of age,conducting high quality selective or non-selective MCV supplementary immunization activities,strengthening high quality measles surveillance,providing more aggressive outbreak responses,and paying more attention to adult susceptible cases.