WASHINGTON (CN) — The Centers for Disease Control and Prevention touted a trio of new studies Friday for offering new insight into the protection that vaccines, and booster shots in particular, provide against the omicron variant.
One study looking at data in 10 states found that getting three doses of the Pfizer or Moderna vaccine was 82% effective at preventing hospitalizations and urgent care or emergency room visits, while protection from just two doses of the vaccine was much lower, particularly for people who were more than six months out from their second shot.
Another study analyzing case counts and deaths in 25 states from April through December found people with booster shots, as compared with people who had gotten two shots or were not vaccinated at all, were less likely to get infected with omicron or delta.
CDC researchers also led a Journal of the American Medical Association study released Friday that examined positive Covid-19 cases from more than 4,600 U.S. testing sites. This analysis found that people with three doses of Modern or Pfizer who were infected with omicron were 66% less likely to be symptomatic, while two doses provided no significant protection.
These reports provide the first detailed U.S. data on the critical role booster shots play in the fight against the highly transmissible variant of the Covid-19 virus.
"As we continue to face the omicron variant, representing over 99% of infections in the United States today, I urge all who are eligible to get their booster shot to get it as soon as possible," CDC Director Rochelle Walensky said.
The bottom line: Omicron, as with many variants that have extensive mutations, is more infectious than its predecessors, but vaccines, and booster shots in particular, continue to provide substantial protection against hospitalizations and deaths.
"Get your vaccinations up to date. It is essential for your protection," Dr. Anthony Fauci, White House chief medical advisor, said.
In a country where fewer than 40% of people eligible to get a booster shot have gotten one, however, the CDC faces increasing pressure about whether it will change its definition of "fully vaccinated" to encourage vaccinations — a query Walensky did not provide a clear answer on.
"What we really are working to do is pivot the language to make sure that everybody is as up-to-date with their Covid-19 vaccines as they personally could be, should be, based on when they got their last vaccine," Walensky said.
Covid-19 cases remain high across the United States, meanwhile, and access to testing and protective masks remain a hurdle for lowering case counts.
Jeffrey Zients, White House coronavirus response coordinator, said the administration is working on its program to provide free N95 and KN95 masks at some pharmacies and health centers, saying they should be available "in the coming days."
Zients also said the government started shipping out free rapid tests to households Thursday, part of a program that began this week to mail four free at-home tests to households.
"Because of the administration's actions, we are moving toward a time when Covid won't disrupt our daily lives, where Covid won't be a constant crisis, but something we protect against and treat," Zients said.
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