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  • New research from the CDC finds that a COVID-19 booster vaccine dose is extremely protective against getting very ill with the Omicron variant.
  • People who’d received a COVID-19 booster dose were far less likely to end up in the emergency department or hospitalized.
  • Another study found that people, especially older adults, who’ve received a booster are better protected against infection and death, compared to the unvaccinated.

The Centers for Disease Control and Prevention (CDC) has published new research that found a third COVID-19 vaccine dose, or booster, provides tremendous protection against getting seriously ill with the Omicron variant of the coronavirus.

“These reports add more evidence to the importance of being up to date with COVID vaccinations — that means getting your primary series and getting boosted when eligible — to protect against severe COVID-19,” Dr. Rochelle Walensky, director of the CDC, said at a White House briefing on Friday.

In one study published by the CDC, researchers analyzed data from 10 states from August 2021 to January 2022.

People who received a third COVID-19 vaccine dose were 82 percent less likely to end up at an emergency department or urgent care clinic during the Omicron wave compared to the unvaccinated, the authors found.

They were also 90 percent less likely to be hospitalized than were the unvaccinated.

Both types of protection were lower during the Omicron wave compared to the Delta wave.

The second study published by the CDC looked at COVID-19 cases and deaths reported in 25 state and local health departments between April and December 2021.

During the Delta wave, protection against infection and death was higher among people who’d received a booster dose, compared with those who were fully vaccinated but not boosted, researchers reported.

Protection against infection was also higher for boosted people during the Omicron wave. Because of the lag in the reporting of COVID-19 deaths, researchers did not have data on deaths during the Omicron wave.

The largest protection occurred for people over age 65, followed by those 50 to 64 years old.

“[The study] clearly shows that those who were unvaccinated had much higher rates of infection and death,” said Dr. Shobha Swaminathan, an associate professor and infectious diseases physician at Rutgers New Jersey Medical School.

In fact, she said unvaccinated people in the study had an almost 20-times higher risk of dying from COVID-19 than the fully vaccinated.

In a third study, published in the Journal of the American Medical Association, researchers looked at data from more than 70,000 people who were tested for coronavirus infection through a pharmacy-based testing program.

Three doses provided more protection against symptomatic infection, compared with two doses or being unvaccinated, the authors found.

Full vaccination and boosters provided less protection against the Omicron variant compared to Delta. Lab studies have found that Omicron is partially able to overcome the protection offered by the vaccines and prior immunity.

The CDC also published additional COVID-19 data last week on its website showing that in December, unvaccinated Americans 50 to 64 years old were 44 times more likely to be hospitalized compared to those who were fully vaccinated and received a third dose.

The hospitalization risk was 49 times higher for unvaccinated people 65 and older.

These studies show that full vaccination and boosters offer a strong defense against infection and hospitalization, including during the Omicron wave.

“These data support what we are seeing in our hospital and institutions across the country,” said Swaminathan. “Most COVID-19 deaths and ICU admissions are among those who are unvaccinated, and [this research] should hopefully encourage more people to get vaccinated and boosted.”

Yet just over 210 million people in the United States, or about 63 percent of the total population, have received two doses of a COVID-19 vaccine. And just under 84 million people, or about 40 percent of the fully vaccinated, have had a booster dose.

The CDC now recommends booster doses for everyone 12 years and older, at least 5 months after the primary series of the Pfizer-BioNTech or Moderna-NIAID vaccines, or at least 2 months after a single dose of the Johnson & Johnson vaccine.

As the importance of boosters becomes clearer, the agency has shifted from encouraging Americans to be “fully vaccinated” to asking them to be “up to date” on their doses.

“If you are eligible for a booster and you haven’t gotten it, you’re not up to date,” Walensky said at the media briefing.