Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil.
Vaccine. 2012 Aug 10;30(37):5541-6. doi: 10.1016/j.vaccine.2012.06.044. Epub 2012 Jun 27.
To combat rising incidence of serogroup C meningococcal disease in the city of Salvador, Brazil, the Bahia state immunization program initiated routine childhood immunization with meningococcal C conjugate vaccine (MenC) in February 2010, followed by mass MenC vaccination of city residents 10-24 years of age from May through August 2010. We analyzed trends in incidence of reported cases of meningococcal disease and serogroup distribution among meningococcal isolates identified in hospital-based surveillance in Salvador from January 2000 to December 2011 and estimated vaccine effectiveness using the screening method. Annual incidence of serogroup C meningococcal disease increased from 0.1 cases per 100,000 population during 2000-2006 to 2.3 in 2009 and 4.1 in 2010, before falling to 2.0 per 100,000 in 2011. Estimated coverage of mass vaccination reached 80%, 67% and 41% among 10-14, 15-19 and 20-24 year olds, respectively. Incidence in 2011 was significantly lower than average rates in 2008-2009 among children <5 years, but reductions among 10-24 year olds were not significant. Among 10-24 year olds, a single dose of MenC vaccine was 100% effective (95% confidence interval, 79-100%) against serogroup C meningococcal disease. Low coverage in the population targeted for mass vaccination may have limited impact on ongoing transmission of serogroup C meningococcal disease despite high vaccine effectiveness.
为了应对巴西萨尔瓦多市 C 群脑膜炎奈瑟菌疾病发病率的上升，巴伊亚州免疫计划于 2010 年 2 月开始对儿童常规使用脑膜炎奈瑟菌 C 型结合疫苗（MenC）进行免疫接种，随后于 2010 年 5 月至 8 月对 10-24 岁的城市居民进行大规模 MenC 疫苗接种。我们分析了 2000 年 1 月至 2011 年 12 月萨尔瓦多基于医院监测报告的脑膜炎病例发病率趋势和脑膜炎奈瑟菌分离株的血清型分布，并使用筛选法估计疫苗效力。C 群脑膜炎奈瑟菌疾病的年发病率从 2000-2006 年的每 10 万人中有 0.1 例上升至 2009 年的 2.3 例和 2010 年的 4.1 例，然后在 2011 年下降至每 10 万人 2.0 例。10-14 岁、15-19 岁和 20-24 岁人群中，大规模疫苗接种的估计覆盖率分别为 80%、67%和 41%。2011 年的发病率明显低于 2008-2009 年 5 岁以下儿童的平均发病率，但 10-24 岁人群的发病率下降并不显著。在 10-24 岁人群中，一剂 MenC 疫苗对 C 群脑膜炎奈瑟菌疾病的效力为 100%（95%置信区间，79-100%）。尽管疫苗效力很高，但目标人群的大规模疫苗接种覆盖率低可能会限制 C 群脑膜炎奈瑟菌疾病的传播。
