RELATED: If You Got This One Vaccine, Get a Booster Now, Virus Expert Warns.ae0fcc31ae342fd3a1346ebb1f342fcb Just hours after Pfizer’s initial announcement, the FDA and CDC sent out their joint statement saying that Americans don’t need booster shots just yet. “Americans who have been fully vaccinated do not need a booster shot at this time,” the July 8 statement reads. This means that more than 158 million fully vaccinated people in the U.S. do not need to start worrying about additional COVID shots, as far as these agencies are concerned The FDA and CDC added that they are “engaged in a science-based, rigorous process to consider whether or when a booster might be necessary.” While they will take data from specific pharmaceutical companies, like Pfizer, into account during their process, the agencies say they won’t decide on a booster timeline with that data alone. “We continue to review any new data as it becomes available and will keep the public informed,” the statement says. “We are prepared for booster doses if and when the science demonstrates that they are needed.” RELATED: For more up-to-date information, sign up for our daily newsletter. Pfizer and its partner BioNTech said that real-world data released from the Israel Ministry of Health shows that vaccine efficacy for infection and symptomatic disease declines six months after initial vaccination—although efficacy in preventing severe COVID still remains high. “That is why we have said, and we continue to believe that it is likely, based on the totality of the data we have to date, that a third dose may be needed within 6 to 12 months after full vaccination,” the manufacturers said. But the research remains conflicted on this, and many experts are not convinced. Paul Offit, MD, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, recently told Business Insider that he believes it may be as long as three to five years before boosters shots are necessary. And a June 28 study published in the journal Nature said that those who got Pfizer may never need a booster after finding evidence that two-dose vaccine regimes result in persistent long-term immunity. “The United States is fortunate to have highly effective vaccines that are widely available for those aged 12 and up. People who are fully vaccinated are protected from severe disease and death, including from the variants currently circulating in the country such as Delta,” the FDA and CDC concluded, saying that unvaccinated individuals are the ones at most pressing risk for COVID. RELATED: If You Did This After Your First Shot, You’re at Risk for the Delta Variant.