The Covid vaccination campaign in the United States cut hospitalizations and deaths by nearly half in the first six months of 2021, new research suggests.
The shots saved nearly 241,000 lives and prevented almost 1.2 million hospitalizations, according to a model published Tuesday in the journal JAMA Network Open.
But as 2021 progressed, the vaccines were met with a significant hurdle that blunted the shots’ effectiveness: People stopped getting vaccinated.
“By late spring and summer vaccine uptake started leveling out,” said Dr. Eric C. Schneider, a senior vice president for policy and research at The Commonwealth Fund who collaborated on the model. “We could have had even greater impact if we had more people vaccinated.”
Even without reaching higher vaccination levels, the vaccines decreased the impact of the alpha variant, a moderately more contagious form of the virus that was first detected in the United Kingdom and began circulating worldwide by the end of 2020. It became the dominant variant in the U.S. in April 2021.
According to researchers from Yale University, the University of Maryland, Canada’s York University and The Commonwealth Fund, vaccinations averted more than 14 million cases of Covid from mid-December 2020, when the first vaccines were authorized, through the end of June 2021, by which point about 50 percent of U.S. adults were vaccinated.
Dr. Sudhakar Venkata Nuti, an internal medicine physician at Massachusetts General Hospital, said the new model confirms that what health officials said about the importance of vaccination against Covid was correct.
“The messaging that we as a health care system provided to the public has been that this vaccine will be helpful to prevent you from getting sick and prevent you from dying. Looking back, what we said was true and we saved lives, reduced suffering and prevented another wave of Covid,” Nuti said. “We wouldn’t have had those benefits if not for vaccines.”
To date, Covid has killed more than 835,000 people in the U.S., a toll that would be lower if more people were vaccinated, Schneider said.
Nearly 208 million people ages 5 and up in the U.S., or 62.5 percent, have been fully vaccinated, with either two doses of an mRNA vaccine or one dose of the Johnson & Johnson vaccine, and more than 75 million have received an additional booster dose. More than 74 percent of eligible Americans have received at least one dose of a Covid vaccine, Centers for Disease Control and Prevention data show.
Nuti said that though the model focused on the first half of 2021, vaccination still remains important, particularly in the face of the extremely contagious omicron variant, now the dominant strain in the U.S.
“With omicron, the likelihood of you being exposed is higher than ever. Getting a vaccine and a booster shot would be the best thing you can do to prevent you and your loved ones from getting really sick,” Nuti said.
Schneider acknowledged that the emergence of omicron as well as other variants has made modeling more challenging.
“Variants have made predictive modeling difficult and the virus keeps surprising us,” he said. Given omicron’s ability to evade immunity, “vaccines aren’t as good now at preventing infection, but are still very good at preventing hospitalization and death.”
“Anything that builds immunity in the population is an important step,” he said.