The study, published Wednesday by the Centers for Disease Control and Prevention, found fully vaccinated adults were 94% less likely to be hospitalized with COVID-19 compared to unvaccinated adults in the same age group. People were considered fully vaccinated two weeks after receiving their second dose of the Moderna or Pfizer vaccines. The J&J vaccine was not included in the study.
In the same age group, those who were partially vaccinated were 64% less likely to be hospitalized with COVID than those who were not vaccinated.
The study said its findings are the first real-world evidence showing that mRNA vaccines prevent severe COVID-19 illness.
“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 P. Walensky 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,” she said. “The results are promising for our communities and hospitals. 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.”
While an earlier study out of Israel confirmed the real-world effectiveness of the Pfizer vaccine, the CDC study is the first to look at both the Pfizer and Moderna vaccines.
The study included data from 24 hospitals in 14 states, with 417 participants in the assessment.
The CDC said the study is the first of many COVID vaccine effectiveness assessments to evaluate the real-world benefits of the vaccines.
The agency said results from the studies “will help inform policy decisions aimed at saving lives and decreasing serious COVID-19 disease as much as possible.”