U.S. adults aged 65 years or older who have been fully vaccinated with Pfizer-BioNTech or Moderna’s COVID-19 vaccines are 94% less likely to be hospitalized with the disease than seniors who were not vaccinated, according to real-world evidence unveiled today by the U.S. Centers for Disease Control and Prevention (CDC).
Partial vaccination was also found to be beneficial, reducing the risk of hospitalization by 64% among older Americans, the agency said.
For the sake of these findings, the CDC considered full vaccination to be achieved two weeks after an individual’s second dose and partial vaccination to come two weeks after a person’s first dose. The agency said that it saw no evidence of protection among those who were still within the two-week antibody window.
These new data represent the first real-world evidence of the two mRNA vaccines authorized by the U.S. Food and Drug Administration for use among those aged 16 years or older.
They are also the first real-world data of the Pfizer-BioNTech vaccine describing U.S. adults, the agency said, as prior studies had assessed its performance in Israel.
“These findings are encouraging and welcome news for the two-thirds of people aged 65 and up who are already fully vaccinated,” CDC Director Rochelle Walensky, M.D., said in a statement. “COVID-19 vaccines are highly effective and these real-world findings confirm the benefits seen in clinical trials, preventing hospitalizations among those most vulnerable.”
To conduct its assessment, the CDC said that it collected hospitalization data from two surveillance networks originally established to monitor serious influenza disease.
Among 24 hospitals in 14 states, the agency reviewed data from 417 participants—187 cases and 230 controls. More than half of these patients were older than 75 years.
CDC said this is the first of many planned efforts to measure the effectiveness of COVID-19 vaccines and that it will be using the data from these projects to craft future vaccine policy.
Evidence of the vaccines’ protection is good news for individuals as well as health providers, Walensky said. For the latter, she said the data are a “promising” sign that facilities are unlikely to face the waves of overwhelming patient volumes fielded by some over the past several months.
“As our vaccination efforts continue to expand, COVID-19 patients will not overwhelm health care systems—leaving hospital staff, beds and services available for people who need them for other medical conditions,” she said.
From a public health perspective, the results come at a time when the supply of the vaccines is beginning to outpace demand within the U.S.
As officials seek to win over those who are hesitant or unwilling to seek out a shot, Department of Health and Human Services Secretary Xavier Becerra recently said that “the most important” strategy going forward will be to clearly showcase the positive results vaccines have already delivered.
“It used to be that most of the deaths we were hearing about from COVID were grandparents, our older populations,” Becerra said Wednesday during an interview today at Aspen Ideas: Health. “Today, two-thirds of all seniors are vaccinated. If you take a look at the numbers when it comes to the people who are getting sick and dying, it’s no longer our seniors. And so, the impact of the vaccine is absolutely out there, proof positive, that if you get vaccinated you can not only stay safe—you can live.”