On Thursday, the Centers for Disease Control and Prevention endorsed COVID-19 vaccine booster shots for elderly and vulnerable Americans.

The move was announced by director Dr. Rochelle Walensky, who backed the CDC Advisory Committee’s recommendation for a Pfizer COVID-19 vaccine booster shot among those more at risk from the novel coronavirus. People aged 65 years or older or in long-term care should receive a shot at least six month after their first two Pfizer shots, as should those aged 50-65. Anyone aged between 18-49 with underlying medical conditions or at increased risk of COVID-19 exposure “because of occupational or institutional setting” may receive a booster shot, too.

The advisory panel butted heads over the decision to allow otherwise healthy front-line workers in healthcare or other occupations to get booster shots, but Walensky maintained it was consistent with the Food and Drug Administration’s authorization of Pfizer booster shots earlier this week.

“As CDC Director, it is my job to recognize where our actions can have the greatest impact,” Dr. Rochelle Walensky said in a statement. “At CDC, we are tasked with analyzing complex, often imperfect data to make concrete recommendations that optimize health. In a pandemic, even with uncertainty, we must take actions that we anticipate will do the greatest good.” 

Getting shots to the unvaccinated population remains the number one priority for the CDC, hence the concern over offering shots to front-line workers and others at higher risk of infection. As Dr. Helen Keipp Talbot of Vanderbilt University said via Associated Press, “We can give boosters to people, but that’s not really the answer to this pandemic. Hospitals are full because people are not vaccinated.”

The CDC noted that it would change its recommendations if new research and evidence suggests more people need booster shots. 

Earlier this week, the FDA announced it had approved a booster shot for people 65 or older, as well as any adult at high risk of suffering severe COVID-19 complications. 

"This pandemic is dynamic and evolving, with new data about vaccine safety and effectiveness becoming available every day," said acting FDA Commissioner Dr. Janet Woodcock. "As we learn more about the safety and effectiveness of COVID-19 vaccines, including the use of a booster dose, we will continue to evaluate the rapidly changing science and keep the public informed."