The Biden administration is expected later this week to recommend that the majority of Americans get a booster shot eight months after their second dose of a COVID-19 vaccine. The boosters would be administered once the vaccines are fully approved by the Food and Drug Administration and the Centers for Disease Control and Prevention signs off on them. An administration official and two sources familiar with the ongoing discussions told CBS News boosters will be recommended for individuals 8 months after being fully vaccinated with the Pfizer or Moderna shot. Federal health officials are waiting for more data before offering guidance for Johnson & Johnson/Janssen vaccine recipients. Studies on the efficacy and safety of mixing different vaccines are still ongoing, so the initial planning is likely for Americans to receive a booster of the same vaccine they were administered for their first two doses. Officials expect that a booster will also be needed for the one-shot Johnson & Johnson vaccine. Full FDA approval of the vaccines is expected in mid- to late-September, according to health officials. The New York Times first reported the administration’s booster shot plans. Last week, U.S. health officials recommended boosters for some with weakened immune systems, such as transplant recipients and certain cancer patients. World Health Organization chief Dr. Tedros Adhanom Ghebreyesus earlier in August asked countries that were further along in their vaccination programs to hold off on administering booster shots until September to allow time for at least 10% of the population of every country to be vaccinated. “I understand the concern of all governments to protect their people from the Delta variant. But we cannot accept countries that have already used most of the global supply of vaccines using even more of it,” Tedros said. Haley Ott contributed reporting.