Frey Kurt
Institute for Disease Modeling, Bill and Melinda Gates Foundation, Seattle, WA 98109, USA.
Vaccines (Basel). 2024 Jul 22;12(7):811. doi: 10.3390/vaccines12070811.
Rubella infection is typically mild or asymptomatic except when infection occurs during pregnancy. Infection in early pregnancy can cause miscarriage, stillbirth, or congenital rubella syndrome. Only individuals that are still susceptible to rubella infection during child-bearing age are vulnerable to this burden. Rubella-containing vaccine (RCV) is safe and effective, providing life-long immunity. However, average age-at-infection increases with increasing vaccination coverage, which could potentially lead to increased disease burden if the absolute risk of infection during child-bearing age increases. The dynamics of rubella transmission were explored using EMOD, a software tool for building stochastic, agent-based infection models. Simulations of pre-vaccine, endemic transmission of rubella virus introduced RCV at varying levels of coverage to determine the expected future trajectories of disease burden. Introducing RCV reduces both rubella virus transmission and disease burden for a period of around 15 years. Increased disease burden is only possible more than a decade post-introduction, and only for contexts with persistently high transmission intensity. Low or declining rubella virus transmission intensity is associated with both greater burden without vaccination and greater burden reduction with vaccination. The risk of resurgent burden due to incomplete vaccination only exists for locations with persistently high infectivity, high connectivity, and high fertility. A trade-off between the risk of a small, future burden increase versus a large, immediate burden decrease strongly favors RCV introduction.
风疹感染通常症状轻微或无症状,除非在孕期发生感染。孕早期感染可导致流产、死产或先天性风疹综合征。只有在育龄期仍易感染风疹的个体才易受这种负担影响。含风疹疫苗(RCV)安全有效,可提供终身免疫。然而,随着疫苗接种覆盖率的提高,平均感染年龄会增加,如果育龄期感染的绝对风险增加,这可能会导致疾病负担加重。使用EMOD(一种用于构建基于主体的随机感染模型的软件工具)探索了风疹传播动态。模拟风疹病毒疫苗接种前的地方性传播,以不同覆盖率引入RCV,以确定疾病负担的预期未来轨迹。引入RCV在大约15年的时间内可降低风疹病毒传播和疾病负担。只有在引入疫苗十多年后,且仅在传播强度持续较高的情况下,疾病负担才可能增加。风疹病毒传播强度低或下降,既与未接种疫苗时负担加重有关,也与接种疫苗后负担大幅减轻有关。因疫苗接种不完全导致负担反弹的风险仅存在于传染性持续高、连通性高和生育率高的地区。在未来负担小幅增加的风险与立即大幅减轻负担之间进行权衡,强烈支持引入RCV。