Ju Jiandong, Chair Professor of Unigroup Finance, Wudaokou School of Finance, Tsinghua University and Director of the Center for International Finance and Economic Research (CIFER), National Institute of Finance, Tsinghua University, and Researchers Chen Xiao, Huang Hanwei, Sun Ruoyan, and Postdoctoral Fellow Jialiang Zhang wrote an article by Impact of vaccination on the COVID-19 pandemic in U.S. states It was officially published on January 28, 2022 in sci journals and nature magazine group journal Scientific Reports.
Note: All authors are co-contributing authors, sorted alphabetically by last name.
The authors thank K.E. Warner and S. Mennemeyer's valuable advice.
Article summary
Governments around the world are aggressively pursuing mass vaccination programmes to end the COVID-19 pandemic. Although the results of randomized controlled trials (RCTs) show high efficacy of the Pfizer and Modena vaccines, there are still limited academic studies on the real-world efficacy of vaccines based on population data. Based on the background of vaccination in the United States during the epidemic, this paper evaluates the effectiveness of COVID-19 vaccination in the early stages of vaccination in the population and predicts the path to herd immunity in the United States.
First, the study used the econometric technique of regression analysis (often used to assess the impact of policies or events) and used US state-level data to assess the role of early vaccination during ongoing outbreaks. The actual proportion of vaccinated people and the total population varies significantly over time across states and is a key source of change in identifying vaccination effectiveness. By comparing the growth rate of new infections in states before and after the launch of the vaccination programme, as well as the growth rate of new hospitalizations, we assessed the role of vaccination in controlling the COVID-19 pandemic. The period from U.S. vaccination in December 2020 to early March 2021 is estimated to have averted a total of 4.4 million new infections (from 33 million to 28.6 million) and about 120,000 new hospitalizations (from 89 to 780,000), which equates to a 1.34 percentage point reduction in the total population infection rate (from 10.10% to 8.76%).
Based on trends in early vaccination programs, this study established a Susceptible-Infected-Recovered (SIR) model with vaccination to predict herd immunity. Predicting the influencing factors of herd immunity through data fitting found that the faster the vaccination rate, the less hesitant the vaccine, and the higher the effectiveness of the vaccine, the faster the herd immunity can be achieved. However, on the one hand, due to the prevalence of vaccination hesitation in the United States, a certain percentage of the population may never be vaccinated; on the other hand, the effectiveness of vaccines against new variants has been reduced, and these factors have greatly delayed the herd immunity date predicted by the model. The above assessment of the real-world effects of early vaccination and the prediction of herd immunity have improved the academic understanding of COVID-19 vaccination and can provide reference and support for future public health policies.
Journal Introduction
Scientific Reports is an SCI journal affiliated with the Nature Publishing Group. Scientific Reports is an open source journal that publishes original research from various fields of natural science, psychology, medicine, and engineering, with an impact factor of 5.134 for the last 5 years. According to the 2020 Journal Citation Reports (JCR) published by Clarivate, Scientific Reports is the 6th most cited journal in the world, with more than 540,000 citations in 2020 and receiving widespread attention in policy documents and the media.
About the author
Ju Jiandong
Tsinghua University Wudaokou School of Finance Tsinghua University School Of Finance Tsinghua University Tsinghua University Tsinghua University School Of Finance School School Of International Finance and Economics Research Center (CIFER) Director of Tsinghua University National Institute of Finance Research Center (CGFR), Distinguished Professor of Shanghai University of Finance and Economics Business School, Chairman of China Council for International Trade Research; research areas focus on international trade, international finance and industry organizations, in the American Economic Review, Journal of International Economics, Journal of Monetary Economics, American Economic Journal and other international first-class academic journals have published many papers, and have won the 2016 Pushan World Economics Outstanding Paper Award, and the 2020 Ministry of Education's 8th Higher Education Scientific Research Outstanding Achievement Award (Humanities and Social Sciences) Book Paper Award First Prize in the Economics Category. In 2021, he was recognized by the Beijing Municipal Commission of Education as "The Main Teacher of Excellent Professional Courses (Public Courses) in Beijing Colleges and Universities".
Chen Xiao
He is a lecturer at the School of International Economics and Trade of the University of International Business and Economics, and a researcher at the Center for International Finance and Economic Research (CIFER) of the National Institute of Finance of Tsinghua University. Ph.D. in Tsinghua University school of economics and management, engaged in international trade related research, the main direction of structure trade and open macro. Over the years, he has been committed to research on international trade theory, and has accumulated a rich knowledge base on the dynamic flow of factors and products in multiple regions. He has published several papers as the first author or corresponding author in core Chinese and English journals such as Transportation Research Part A: Policy and Practice, "World Economy", "Nankai Economic Research", etc., and has participated in or submitted many working papers.
Huang Hanwei
PhD, London School of Economics and Political Science, currently assistant professor in the Department of Economics and Finance, City University of Hong Kong Business School, Research Fellow, Centre for Economic Operations, London School of Economics and Political Sciences, and Centre for International Finance and Economics (CIFER), National Institute of Finance, Tsinghua University. From 2018 to 2019, he worked at University College London as a postdoctoral researcher. His research interests include international trade, industrial organization theory and development economics. Teaching interests include international trade, international finance and macroeconomics. As a reviewer for several international journals, his research on the economic impact of Brexit has been reported by Bloomberg, The Economist, The Financial Times and others. Current major research topics include global value chains, global production networks and the economic impact of global epidemics.
Sun Ruoyan
Ph.D., University of Michigan School of Public Health, M.A. from Johns Hopkins University Bloomberg School of Public Health, and Bachelor of Williams-Mary School. He is currently an Assistant Professor (tenured) professor in the Department of Health Care Organization and Policy at the University of Alabama's Birmingham School of Public Health (UAB) and a fellow at the Center for International Finance and Economic Research (CIFER) at the National Institute of Finance, Tsinghua University. Focusing on the fields of health economics and operations research/decision science, he applies a variety of measurement methods such as proxy model, econometric analysis, social network analysis, mathematical modeling, and optimal control to the study of public health behaviors and the evaluation of public health interventions. The foundation and current focus includes the following areas: 1) mathematical modelling of infectious diseases, 2) analysis of social media data to model COVID-19 trends, and 3) assessment of the cost-effectiveness of public health intervention policies.
Zhang Jialiang
Postdoctoral Fellow, Wudaokou School of Finance, Tsinghua University, and Assistant Researcher, Center for International Finance and Economics (CIFER), National Institute of Finance, Tsinghua University. He received his B.S. and B.S. in Economics from Peking University in 2015 and a Ph.D. in Economics from Peking University in 2020, during which he visited the Department of Economics of the University of Toronto from September 2017 to September 2018 (joint doctoral training), and his research areas include international trade and development economics. The research results have been accepted by journals such as Review of Finance and Scientific Reports, and many working papers have been reviewed or submitted in world-class English journals. He has won the Liao Kaiyuan Scholarship of Peking University, the First Class Academic Scholarship for Doctoral Students of Peking University, the Outstanding Graduate of Beijing Municipality, and the National Scholarship.