Booster shots offer the best protection against the Omicron variant, three large new studies from the US Centers for Disease Control and Prevention have found.
The studies found that vaccinated people who received a Pfizer or Moderna booster shot were much less likely to face serious illness or death from Omicron, which now accounts for 99% of infections in the United States.
Together, the three studies looked at millions of cases, hundreds of thousands of emergency room visits, and tens of thousands of adult hospitalizations.
A study that looked at nearly 88,000 hospitalizations in 10 states between December and January, as Omicron became the dominant strain in the United States, found that boost was 90% effective in preventing hospitalizations.
This compares to only 57% protection for those who had received two injections when the second dose was over six months old.
A second study focused on Covid-19 case and death rates in 25 states from early April through Christmas. People who were boosted had the highest protection against coronavirus infection, both during the period when Delta was dominant and also when Omicron took over.
The findings echo studies in Germany, South Africa and the UK that indicate available vaccines are less effective against Omicron than earlier versions of the coronavirus, but still offer significantly improved protection.
“Data from other countries also showed a significant benefit in getting the booster, but this really shows it in the United States,” said Akiko Iwasaki, an immunologist at Yale University. the New York Times.
“These numbers should be very compelling.”
Less than half of Americans eligible for double vaccination have received their booster shots.
The CDC recommends that everyone 12 and older get booster shots. Pfizer and Moderna recipients should be boosted five months after their second injection, or those who received the single-shot Johnson & Johnson vaccine are recommended to receive theirs two months later.
Agencies contributed to this report
The Independent Gt