New York had 11.7 fewer COVID-19 deaths per 10,000 adults, and Hawaii had 1.1 fewer deaths per 10,000 than would have occurred without vaccinations, the study shows. The rest of the states fell somewhere in between, with the average state experiencing five fewer COVID-19 deaths per 10,000 adults.
At a national level, this means that instead of the 550,000 COVID-19 deaths that occurred by early May, there would have been 709,000 deaths in the absence of a vaccination campaign, according to the study.
Researchers from RAND and Indiana University created models to estimate the number of COVID-19 deaths that would have happened without vaccinations. The difference between the actual number of deaths and those estimates provides a measure of the number of COVID-19 deaths averted by the vaccination campaign.
Information about vaccine doses administered in each state came from the Bloomberg COVID-19 Vaccine Tracker, and data on COVID-19 deaths for each state came from The New York Times’ Coronavirus (COVID-19) Data in the United States database.
The study spanned the period from Dec. 21, 2020 to May 9, 2021. The U.S. Food and Drug Administration issued its first emergency use authorization (EUA) for a COVID-19 vaccine to Pfizer/BioNTech on December 11, followed by an EUA for the Moderna vaccine on December 18 and one for Johnson & Johnson’s vaccine on Feb. 27, 2021.
Varied by state
There were wide variations in the speed and extent of the vaccination campaigns in various states, the researchers found. For example, West Virginia was the first state to reach 10 doses per 100 adults, reaching that goal on Jan. 16, 2021, and Idaho was the last state to hit that mark, on Feb. 4, 2021. Alaska was the first to reach 20 doses per 100 adults, on January 29, and Alabama was the last to do it, on February 21.
On May 6, California was the first state to administer 120 doses per 100 adults, but many states have still not reached that milestone.
The median number of days between the milestones of 10 and 20 doses per 100 adults was 19 days, and the median number of days between 20 and 40 doses per 100 adults was 24 days.
Hard to establish causality
The researchers emphasized that “establishment of causality is challenging” in comparing individual states’ vaccination levels with their COVID-19 mortality rates.
Aside from the study being observational, they pointed out, the analysis “relied on variation in the administration of COVID-19 vaccines across states … Vaccine administration patterns may be associated with declining mortality because of vaccine prevention of deaths and severe complications as state-level vaccine campaigns allocated initial doses to the highest-risk populations with the aim of immediately reducing COVID-19 deaths.”
Nevertheless, the authors note, “clinical trial evidence has shown that COVID-19 vaccines have high efficacy. Our study provides support for policies that further expand vaccine administration, which will enable larger populations to benefit.”