The director of the US Centers for Disease Control, Dr Rochelle Walensky, has cautioned the country against relying on booster shots to end the COVID-19 pandemic. “I want to be clear: We will not boost our way out of this pandemic,” she said. As more Americans become eligible for Pfizer boosters, the US will still have to ramp up its vaccination campaign for the pandemic to subside, Walensky said. “The most vulnerable are those unvaccinated,” Walensky said Friday after the CDC Friday approved a third shot of Pfizer’s Covid-19 vaccine. US Surgeon General Dr. Vivek Murthy said people who are six months out from their last dose of the Pfizer vaccine are eligible for a booster if they fall into one of three high-risk groups.

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These include people who are 65 or older, or have a medical condition such as obesity, diabetes, high blood pressure, and chronic kidney disease that puts them at high risk of severe illness with COVID-19. People eligible for the boosters also include those who work or live in a setting where they are at high risk of exposure to COVID-19, including health care workers, teachers, those living in shelters or prisons and grocery store workers.

The Food and Drug Administration “is working with Moderna and J&J to get and process their data as quickly as possible with the goal of making booster recommendations for Moderna and J&J recipients in the coming weeks,” Murthy said.

The US has fully vaccinated more than 55% of all residents as of Friday, while 75% of the vaccine-eligible received at least one dose of inoculation.

Since the start of the pandemic, the US has reported over 42.1 million COVID-19 cases and more than 674,000 deaths, making it the worst-affected country. With only 54% of Americans having been fully vaccinated, the US also lags behind its peers like Canada and Britain, which have fully vaccinated 69% and 65% of their populations, respectively.

The Joe Biden administration announced on September 9 new vaccine mandates that will require some 80 million workers to provide proof of vaccination or undergo weekly testing for coronavirus.