Shen Rui, Xu Jiawei, Li Yugang, Yu Jianxing, Sun Na, Xu Zilu, Xu Xueying, Liu Xiao, Liu Yang, Li Bosong, Qi Li, Feng Luzhao
Public Health Emergency Management Innovation Center, School of Population Medicine and Public Health, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; Key Laboratory of Pathogen Infection Prevention and Control, Peking Union Medical College, Ministry of Education, Beijing, China; State Key Laboratory of Respiratory Health and Multimorbidity, Beijing, China.
Chongqing Center for Disease Control and Prevention (Chongqing Academy of Preventive Medicine), Chongqing, China.
Int J Infect Dis. 2025 Jul;156:107910. doi: 10.1016/j.ijid.2025.107910. Epub 2025 Apr 24.
Despite high vaccination coverage, pertussis resurgence in megacities challenges conventional control strategies. We investigated epidemiological patterns and policy impacts in a densely populated urban setting in Chongqing, China.
Using population-based surveillance data (2005-2024) from Chongqing (population 32.1 million; DTP3 coverage >97%), we conducted hierarchical Bayesian spatial modeling and age-structured Susceptible-Infected-Recovered-Vaccinated transmission analysis. We assessed four sequential policy transitions and simulated four vaccination strategies over three years (2025-2027) to evaluate their potential impact.
Annual pertussis incidence increased from 0.25 to 70.82/100,000. Infants showed highest absolute risk, while children aged 6-7 years demonstrated elevated risk (RR: 0.55 and 0.54, respectively). Urban areas showed marginally elevated risk (RR: 1.04, 95% CI: 1.00-1.07). Molecular diagnostics implementation revealed substantial hidden transmission (RR: 82.65, 95% CI: 73.47-92.99). Modeling projected extended school-age boosters (ages 5-7 years) would reduce incidence by 47.93%, targeted vaccination of ages 6-7 years achieved 36.64% reduction, and the national benchmark with 6-year booster reduced incidence by 19.09%. All strategies provided substantial indirect protection to infants without direct intervention.
Enhanced molecular surveillance uncovered substantial hidden transmission in urban settings. Strategic school-age targeted vaccination could effectively disrupt urban transmission chains while protecting vulnerable infants.
尽管疫苗接种覆盖率很高，但大城市中百日咳的卷土重来对传统控制策略构成了挑战。我们调查了中国重庆人口密集的城市环境中的流行病学模式和政策影响。
利用重庆（人口3210万；三联疫苗第三剂接种覆盖率>97%）基于人群的监测数据（2005 - 2024年），我们进行了分层贝叶斯空间建模和年龄结构的易感 - 感染 - 康复 - 接种传播分析。我们评估了四个连续的政策转变，并在三年（2025 - 2027年）内模拟了四种疫苗接种策略，以评估它们的潜在影响。
百日咳年发病率从0.25/10万增至70.82/10万。婴儿的绝对风险最高，而6 - 7岁儿童的风险有所升高（相对风险分别为0.55和0.54）。城市地区的风险略有升高（相对风险：1.04，95%可信区间：1.00 - 1.07）。分子诊断方法的应用揭示了大量隐匿传播（相对风险：82.65，95%可信区间：73.47 - 92.99）。模型预测，延长学龄期加强免疫（5 - 7岁）可使发病率降低47.93%，针对6 - 7岁儿童的靶向接种可使发病率降低36.64%，采用6岁加强免疫的国家基准可使发病率降低19.09%。所有策略在没有直接干预的情况下都为婴儿提供了显著的间接保护。
强化分子监测揭示了城市环境中大量的隐匿传播。针对学龄期的策略性疫苗接种可有效打破城市传播链，同时保护脆弱的婴儿。
