The Pfizer-BioNTech and Moderna COVID-19 vaccines were 94 percent effective at preventing hospitalizations among adults aged 65 and older who were fully vaccinated, according to the CDC's latest Morbidity and Mortality Weekly Report published April 28.
The findings build on clinical trial data by providing vaccine efficacy data in real-world settings, the CDC said. The analysis involved 417 adults who tested positive for COVID-19 between January and March.
One dose of the vaccine, considered partial vaccination, was 64 percent effective against hospitalization among older adults, according to the report.
"Moreover, in assessing the impact of receiving only a single dose, no significant vaccine effectiveness <14 days after the first … was detected," researchers noted, adding that this "highlights the continued risk for severe illness shortly after vaccinated, before a protective immune response has been achieved." As a result, vaccinated adults should continue taking COVID-19 precautions at least 14 days after receiving their second dose, the report said.
To view the full report, click here.