Lifestyle Health FDA Authorizes Pfizer COVID Booster Shot for Some High-Risk Populations The single booster shot must be administered at least six months after completion of the first two doses By Katie Campione Katie Campione Digital News Writer, PEOPLE People Editorial Guidelines Published on September 22, 2021 11:14 PM Share Tweet Pin Email Pfizer-BioNTech COVID vaccine. Photo: Marcos del Mazo/LightRocket via Getty The Food and Drug Administration has authorized a booster shot for Pfizer's COVID-19 vaccine among some populations. The single booster shot must be administered at least six months after completion of the first two doses. Those eligible to receive the booster include individuals 65 years of age and older, anyone older than 18 who is at high risk of severe COVID-19, and those 18 and over who are at risk of serious complications from COVID-19 due to high exposure at their job. Some of the populations who fall under these categories are "health care workers, teachers and day care staff, grocery workers and those in homeless shelters or prisons," acting FDA Commissioner Janet Woodcock, M.D., said in a statement Wednesday. The latest authorization amends the FDA's previous emergency use authorization for the Pfizer vaccine. In August, the initial two-dose series of Pfizer's shot was granted full approval by the FDA for people 16 years and older. Pfizer Says Its COVID-19 Vaccine Is 'Safe, Well Tolerated' Among Kids 5 to 11 with Lower Doses A dose of Pfizer's COVID-19 vaccine. Daniel Pockett/Getty "This pandemic is dynamic and evolving, with new data about vaccine safety and effectiveness becoming available every day," Woodstock said. "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." More than 99 million people in the United States have received both doses of the Pfizer COVID-19 vaccine as of Sept. 22, according to the Centers for Disease Control and Prevention. Earlier this week, the company said its COVID-19 vaccine is good to go for children ages 5 to 11 and it plans to seek approval from the FDA and other agencies soon. Never miss a story — sign up for PEOPLE's free weekly newsletter to get the biggest news of the week delivered to your inbox every Friday. The first test results from this age group reported that there was a "favorable safety profile" as well as "robust neutralizing antibody responses" in the kids, using a smaller dose in the two shots than older people would receive (10 µg instead of 30 µg). They said the results showed the "vaccine was safe, well-tolerated" among children. RELATED VIDEO: Cedric The Entertainer Calls Pfizer the Neiman Marcus of Vaccines at the Emmys The vaccine is still under emergency use approval for kids aged 12 to 15 as the FDA continues to fully vet the shot. "Over the past nine months, hundreds of millions of people ages 12 and older from around the world have received our COVID-19 vaccine. We are eager to extend the protection afforded by the vaccine to this younger population, subject to regulatory authorization, especially as we track the spread of the Delta variant and the substantial threat it poses to children," Albert Bourla, chairman and CEO of Pfizer, said in a statement. "Since July, pediatric cases of COVID-19 have risen by about 240 percent in the U.S. — underscoring the public health need for vaccination," Bourla continued. "These trial results provide a strong foundation for seeking authorization of our vaccine for children 5 to 11 years old, and we plan to submit them to the FDA and other regulators with urgency." As information about the coronavirus pandemic rapidly changes, PEOPLE is committed to providing the most recent data in our coverage. Some of the information in this story may have changed after publication. For the latest on COVID-19, readers are encouraged to use online resources from the CDC, WHO and local public health departments.PEOPLE has partnered with GoFundMe to raise money for the COVID-19 Relief Fund, a GoFundMe.org fundraiser to support everything from frontline responders to families in need, as well as organizations helping communities. For more information or to donate, click here.