Three highly effective COVID-19 vaccines are available in the U.S. These vaccines have been shown to slow the spread of the virus and reduce COVID-19 deaths. About half of the population has been fully vaccinated as of August 2021. But vaccination rates have varied across the country, with some states proceeding much faster than others.
A team led by Drs. Sumedha Gupta of Indiana University and Christopher Whaley of the RAND corporation analyzed how the vaccine rollout affected COVID-19 deaths. Their study is one of the first to assess the impact of state-level vaccination campaigns.
NIH’s National Institute on Aging (NIA) supported the study. The findings appeared in Health Affairs on August 18, 2021.
To determine the speed of vaccination in each state, researchers used data from government websites and official statements. The study analyzed the period from December 21, 2020, to May 9, 2021. They compared the amount of time each state took to reach a series of milestones—starting with five vaccine doses per 100 adults, up to 120 doses per 100 adults. They also calculated the number of vaccine doses per 100 adults at the end of each week.
The team used the data to create a statistical model. They then examined the relationship between state vaccination intensity and changes in COVID-19 deaths. The model accounted for the lag between vaccination and effects on death rates.
Based on the model, COVID-19 vaccines prevented more than 139,000 deaths during the first five months they were available. About 570,000 COVID-19 deaths had occurred in the U.S. by May 9; the model projected about 709,000 deaths would have occurred without the vaccines. The researchers estimated that the economic value of preventing these deaths was between $625 billion and $1.4 trillion.
The estimated reduction in deaths varied among states. In New York, vaccinations led to an estimated 11.7 fewer COVID-19 deaths per 10,000. Hawaii had the smallest estimated reduction, with 1.1 fewer deaths per 10,000.
The study had limitations that may have affected these estimates. For example, the researchers could not distinguish the role of vaccination from increases in natural immunity or social distancing policies on the numbers of COVID-19 deaths. Despite these limitations, the results highlight the crucial role of vaccinations in saving lives during the pandemic.
“This study brings into focus the dramatic success of the early months of the nation’s coronavirus vaccine rollout,” Whaley says.
The findings support policies that further expand vaccine administration, particularly to low-income and minority populations.