Yang Haibo, Nie Hao, Zhou Dewei, Wang Yujia, Zuo Wei
Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200092, China.
State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, Guangzhou Medical University, Guangzhou 510120, China.
Vaccines (Basel). 2022 Aug 25;10(9):1392. doi: 10.3390/vaccines10091392.
Omicron, the current SARS-CoV-2 variant of concern, is much more contagious than other previous variants. Whether strict lockdown could effectively curb the transmission of Omicron is largely unknown. In this retrospective study, we compared the strictness of government lockdown policies in Shanghai and other countries. Based on the daily Omicron case number from 1 March 2022 to 30 April 2022, the effective reproductive numbers in this Shanghai Omicron wave were calculated to confirm the impact of strict lockdown on Omicron transmission. Pearson correlation was conducted to illustrate the determining factor of strict lockdown outcomes in the 16 different districts of Shanghai. After a very strict citywide lockdown since April 1st, the average daily effective reproductive number reduced significantly, indicating that strict lockdown could slow down the spreading of Omicron. Omicron control is more challenging in districts with higher population mobility and lockdown is more likely to decrease the number of asymptomatic carriers than the symptomatic cases. All these findings indicate that the strict lockdown could curb the transmission of Omicron effectively, especially for the asymptomatic spread, and suggest that differentiated COVID-19 prevention and control measures should be adopted according to the population density and demographic composition of each community.
奥密克戎是目前引起关注的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）变体，其传染性远高于以往的其他变体。严格封锁是否能有效遏制奥密克戎的传播在很大程度上尚不清楚。在这项回顾性研究中，我们比较了上海和其他国家政府封锁政策的严格程度。根据2022年3月1日至2022年4月30日的每日奥密克戎病例数，计算了上海这波奥密克戎疫情中的有效繁殖数，以确认严格封锁对奥密克戎传播的影响。进行了Pearson相关性分析，以阐明上海16个不同区严格封锁结果的决定因素。自4月1日起实施非常严格的全市封锁后，平均每日有效繁殖数显著下降，表明严格封锁可减缓奥密克戎的传播。在人口流动性较高的区，奥密克戎防控更具挑战性，而且封锁更有可能减少无症状携带者的数量，而非有症状病例的数量。所有这些发现表明，严格封锁可有效遏制奥密克戎的传播，尤其是针对无症状传播，并建议应根据每个社区的人口密度和人口构成采取差异化的新冠疫情防控措施。
