The U.S. government’s top infectious disease expert says a booster COVID-19 vaccination will be recommended for people with a weakened immune system. Speaking to television news program CBS This Morning, Dr. Anthony Fauci said Thursday that he expected the U.S. Food and Drug Administration, or FDA, to recommend the booster shot very soon. People with a weakened immune system are those who undergo major surgery, are being treated for cancer or have other serious health conditions. For groups such as old people, Fauci said health officials are still collecting information. But he added that “it is likely to happen at some point in the future.” Fauci noted that vaccine efficacy would not last forever. Earlier this year, the head of Pfizer told CNBC that people will “likely” need a booster shot within 12 months. And drug maker Johnson & Johnson suggested that people might need a COVID-19 shot yearly like a flu vaccine. Fauci advised people to get the same kind of vaccine that they had received the first time. The FDA has so far approved vaccines from Pfizer-BioNTech, Moderna and Johnson & Johnson for emergency use in the United States.