CDC Director Dr. (((Rochelle Walensky))) said Thursday that Americans may not need yearly Covid-19 booster shots. Walensky suggested a third shot may sufficiently strengthen the long-term protection of Pfizer’s or Moderna’s vaccines. Walensky’s remarks come a day after she and other top U.S. health officials said they plan to start offering boosters to all eligible Americans eight months after their second vaccine shots. The effectiveness of mRNA vaccines lessens over time, particularly for anyone at high risk for dangerous coronavirus complications or for those who were immunized early in the vaccine rollout, Walensky and several of the country’s top medical officials said in a statement Wednesday. “This virus has been humbling, so **I don’t want to say never, but we are not necessarily anticipating that you will need this annually**,” Walensky said in an interview Thursday on the CBS program “This Morning.” “It does look like after this third dose, you get a really robust response, and so we will continue to follow the science both on the vaccine side but also on the virus side.”