Department of Laboratorial Science and Technology & Vaccine Research Center, School of Public Health, Peking University, Beijing, China.
Beijing Tongzhou Center for Diseases Prevention and Control, Institute for Infectious Diseases and Endemic Diseases Prevention and Control, Beijing, China.
J Med Virol. 2022 Aug;94(8):3801-3810. doi: 10.1002/jmv.27803. Epub 2022 Apr 28.
Influenza-like illness (ILI) varies in intensity year by year, generally keeping a stable pattern except for great changes of its epidemic pattern. Of the most impacting factors, urbanization has been suggested as shaping the intensity of influenza epidemics. Besides, growing evidence indicates the nonpharmaceutical interventions (NPIs) to severe acute respiratory syndrome coronavirus 2 offer great advantages in controlling infectious diseases. The present study aimed to evaluate the impact of urbanization and NPIs on the dynamic of ILI in Tongzhou, Beijing, during January 2013 to March 2021. ILI epidemiological surveillance data in Tongzhou district were obtained from Beijing Influenza Surveillance Network and separated into three periods of urbanization and four intervals of coronavirus disease 2019 pandemic. Standardized average incidence rates of ILI in each separate stages were calculated and compared by using Wilson method and time series model of seasonal ARIMA. Influenza seasonal outbreaks showed similar epidemic size and intensity before urbanization during 2013-2016. Increased ILI activity was found during the process of Tongzhou's urbanization during 2017-2019, with the rate difference of 2.48 (95% confidence interva [CI]: 2.44, 2.52) and the rate ratio of 1.75 (95% CI: 1.74, 1.76) of ILI incidence between preurbanization and urbanization periods. ILI activity abruptly decreased from the beginning of 2020 and kept at the bottom level almost in every epidemic interval. The top decrease in ILI activity by NPIs was shown in 5-14 years group in 2020-2021 influenza season, as 92.2% (95% CI: 78.3%, 95.2%). The results indicated that both urbanization and NPIs interrupted the epidemic pattern of ILI. We should pay more attention to public health when facing increasing population density, human contact, population mobility, and migration in the process of urbanization. NPIs and influenza vaccination should be implemented as necessary measures to protect people from common infectious diseases like ILI.
流感样疾病 (ILI) 的强度每年都有所不同，通常保持稳定的模式，除了流行模式的巨大变化。在最具影响力的因素中，城市化被认为是塑造流感流行强度的因素。此外，越来越多的证据表明，针对严重急性呼吸综合征冠状病毒 2 的非药物干预措施 (NPI) 在控制传染病方面具有巨大优势。本研究旨在评估城市化和 NPI 对 2013 年 1 月至 2021 年 3 月北京通州区 ILI 动态的影响。ILI 流行病学监测数据来自北京流感监测网络，并分为城市化三个阶段和 2019 年冠状病毒病大流行四个区间。采用 Wilson 法和季节性 ARIMA 时间序列模型计算并比较每个单独阶段的 ILI 标准化平均发病率。在城市化之前的 2013-2016 年，流感季节性暴发表现出相似的流行规模和强度。在 2017-2019 年通州区城市化进程中，ILI 活动增加，ILI 发病率差异为 2.48（95%置信区间 [CI]：2.44，2.52），发病率比为 1.75（95% CI：1.74，1.76）。从 2020 年初开始，ILI 活动急剧下降，并在几乎每个流行区间都保持在较低水平。2020-2021 流感季，NPI 对 ILI 活动的最大降幅出现在 5-14 岁组，降幅为 92.2%（95%CI：78.3%，95.2%）。结果表明，城市化和 NPI 都中断了 ILI 的流行模式。在城市化进程中，我们应更加关注人口密度增加、人际接触、人口流动和迁移对公共卫生的影响。应实施 NPI 和流感疫苗接种等必要措施，保护人们免受 ILI 等常见传染病的侵害。
