A new study published this week found that the second COVID-19 booster made available to US adults over 50 this year was highly effective at protecting nursing home residents from hospitalizations and deaths, all and that its ability to prevent infections was not as powerful.
The analysis, published in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report, compared nursing home residents who received a second dose of the original mRNA booster with those who did not. they received the additional vaccine.
According to the study, the second shot was 90 percent effective in preventing coronavirus-related deaths and 74 percent effective in preventing severe cases that led to hospitalizations or deaths.
However, the injection was about 26% effective at preventing infection. This study looked at cases between March 29 and July 25. It was during this period that the omicron BA.5 subvariant grew to become dominant in the US.
By the end of July, BA.5 accounted for four out of five coronavirus cases, and experts had noted its ability to evade protection from immunization and prior infection.
All 9,527 nursing home residents included in the study had received their booster within 60 days when the researchers followed them. To be eligible, participants had to have been in a nursing home for more than 100 days, spent less than 10 outside the facility, and had received three prior vaccine doses, with the last dose received with more than 120 days before.
Nearly 200 nursing homes in 19 states were included in the study.
Nursing homes have been disproportionately affected by the coronavirus throughout the pandemic. About three out of four deaths from COVID-19 have been among people over 65. When the delta variant spread across the United States last year, deaths from the coronavirus rose at a faster rate in nursing homes than in the rest of the country.
“These findings suggest that among nursing home residents, second booster doses of the COVID-19 mRNA vaccine provided additional protection over first booster doses against serious outcomes of COVID-19 over time of emerging Omicron variants,” the researchers wrote.
“Facilities should continue to ensure that nursing home residents are up-to-date with their COVID-19 vaccinations, including booster doses of the bivalent vaccine, to prevent serious outcomes from COVID- 19”.
White House COVID-19 response coordinator Ashish Jha praised the study’s findings.
“That’s why we’re so focused on making sure people, especially those at high risk, get the latest vaccine,” Jha tweeted.
If they have not recently been vaccinated again or have been infected with the virus, many of the participants in this study could now receive the omicron-specific bivalent COVID-19 booster. The updated shot was authorized in late August.
The White House has strongly encouraged eligible people to get the bivalent booster, hoping to avoid a further surge in coronavirus cases in the fall and winter. The dose has been dogged by some uncertainty since it was approved before a full human study was completed, with Pfizer and Moderna submitting animal data, as is done for annual flu shots.
Pfizer and Moderna have recently filed applications seeking authorization from the Food and Drug Administration to administer their injections in younger populations. Pfizer’s bivalent booster is licensed for children up to age 12, while Moderna’s is only licensed for adults.