(AP) – U.S. regulators are allowing people 50 and older to get another booster dose of the Pfizer or Moderna COVID-19 vaccine. The Food and Drug Administration’s decision aims to offer extra protection to the most vulnerable in case the virus rebounds. The FDA said Tuesday that age group can seek a fourth dose at least four months after their previous booster. With COVID-19 cases currently low, it’s not clear if they should rush out and get one. There’s limited evidence to tell how much benefit another booster could offer right now. The FDA ruled without input from its independent advisers.