Simulating potential outbreaks of Delta and Omicron variants based on contact-tracing data:A modelling study in Fujian Province,China  

作　　者：Yichao Guo Wenjing Ye Zeyu Zhao Xiaohao Guo Wentao Song Yanhua Su Benhua Zhao Jianming Ou Yanqin Deng Tianmu Chen 

机构地区：[1]State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics,School of Public Health,Xiamen University,Xiamen City,361102,Fujian Province,PR China [2]Fujian Provincial Center for Disease Control and Prevention,Fujian Province,PR China

出　　处：《Infectious Disease Modelling》2023年第1期270-281,共12页传染病建模（英文）

基　　金：supported by the Bill&Melinda Gates Foundation(INV-005834),Natural Science Foundation of Fujian Province(NO.2021J01353,NO.2020J01094);National Science and Technology Major Project of the Ministry of Science and Technology of China(NO.2018ZX10734402-007);Research on accurate prediction and timely response system for out-breaks of new infectious diseases(SRPG2200702);Fundamental Research Funds for the Central Universities(No.20720230001).

摘　　要：Although studies have compared the relative severity of Omicron and Delta variants by assessing the relative risks,there are still gaps in the knowledge of the potential COVID-19 burden these variations may cause.And the contact patterns in Fujian Province,China,have not been described.We identified 8969 transmission pairs in Fujian,China,by analyzing a contact-tracing database that recorded a SARS-CoV-2 outbreak in September 2021.We estimated the waning vaccine effectiveness against Delta variant infection,contact patterns,and epidemiology distributions,then simulated potential outbreaks of Delta and Omicron variants using a multi-group mathematical model.For instance,in the contact setting without stringent lockdowns,we estimated that in a potential Omicron wave,only 4.7%of infections would occur in Fujian Province among individuals aged>60 years.In comparison,58.75%of the death toll would occur in unvaccinated individuals aged>60 years.Compared with no strict lockdowns,combining school or factory closure alone reduced cumulative deaths of Delta and Omicron by 28.5%and 6.1%,respectively.In conclusion,this study validates the need for continuous mass immunization,especially among elderly aged over 60 years old.And it confirms that the effect of lockdowns alone in reducing infections or deaths is minimal.However,these measurements will still contribute to lowering peak daily incidence and delaying the epidemic,easing the healthcare system's burden.

关 键 词：Contact tracing Vaccine effectiveness Variant of concern Mathematical model COVID-19 

分 类 号：R511[医药卫生—内科学] R181.3[医药卫生—临床医学]