The Centers for Disease Control and Prevention on Friday said all adults 18 and older can get a COVID-19 booster shot from Pfizer or Moderna.

Booster shots have demonstrated the ability to safely increase peoples protection against infection and severe outcomes and are an important public health tool to strengthen our defenses against the virus as we enter the winter holidays, CDC Director Rochelle Walensky said in a statement. Based on the compelling evidence, all adults over 18 should now have equitable access to a COVID-19 booster dose.

A CDC and Prevention panel on Friday afternoon endorsed making Pfizer and Moderna COVID-19 boosters available to all adults. With the CDCs full approval, tens of millions more Americans six months past their last Pfizer or Moderna shot can now get an extra dose of protection before the new year.

Earlier Friday, the U.S. Food and Drug Administration amended its emergency use authorizations to allow all adults to get a single booster dose from Pfizer or Moderna at least six months after being fully vaccinated.

Pfizer, Moderna and Johnson & Johnson booster shots were authorized previously but only for certain eligible groups : people over age 65, adults with health conditions that put them at risk for severe COVID-19 or those in jobs that have high exposure to coronavirus cases.

Health officials say its fine to mix and match booster shots, meaning people can get a Pfizer or Moderna booster shot, even if they originally got a Johnson & Johnson vaccine.

Just 59% of people of all ages in the U.S. are currently fully vaccinated .