Dutch National Institute for Public Health and the Environment (RIVM), Bilthoven.
Euro Surveill. 2014 Apr 24;19(16):20776. doi: 10.2807/1560-7917.es2014.19.16.20776.
We describe a mumps outbreak in a highly-vaccinated population attending a party at a youth club. In a retrospective cohort study with 60 of approximately 100 participants responding, vaccination status was verified for 58/59 respondents, of whom 54 were vaccinated twice and four once. The attack rate was 22% (13 cases, all vaccinated), with smoking at the party (risk ratio (RR) 3.1; 95% confidence interval (CI): 1.6–6.0, p=0.001) and age ≥21 years (RR 4.7; 95% CI: 2.1–10.2, p<0.0001) as risk factors for disease in the binominal regression analysis. Mild upper respiratory illness was also highly prevalent in those who did not meet the mumps case definition (n=46) after the party, suggesting that mumps virus infection may cause mild disease in vaccinated individuals. Our investigation adds toevidence that crowded social events and smoking may facilitate spread of mumps virus among vaccinated populations, with waning immunity playing a role. The suggestion that mumps virus infection in vaccinated individuals may manifest as mild upper respiratory illness could have implications for transmission and warrants further investigation.
我们描述了一起在青年俱乐部举行的聚会上发生的麻疹暴发事件，该聚会参与者均为高度接种疫苗的人群。在一项回顾性队列研究中，约有 100 名参与者中的 60 名做出了回应，其中 58/59 名应答者的疫苗接种状态得到了验证，其中 54 人接种了两剂，4 人接种了一剂。发病率为 22%（13 例，均已接种疫苗），在聚会上吸烟（风险比（RR）3.1；95%置信区间（CI）：1.6–6.0，p=0.001）和年龄≥21 岁（RR 4.7；95% CI：2.1–10.2，p<0.0001）是二项式回归分析中疾病的危险因素。在聚会后，即使不符合麻疹病例定义（n=46），那些人也出现了高度普遍的轻度上呼吸道疾病，这表明麻疹病毒感染可能在接种疫苗的个体中引起轻度疾病。我们的调查结果进一步证实了拥挤的社交活动和吸烟可能促进麻疹病毒在接种人群中的传播，而免疫减弱也起到了一定作用。接种疫苗的个体中麻疹病毒感染可能表现为轻度上呼吸道疾病的这一说法可能对传播产生影响，值得进一步调查。
