“Before we start talking about a fourth shot, it will be very important for us to determine the durability of protection, particularly against severe disease for the third shot booster of an mRNA and the second shot of a J&J,” Fauci said. “Right now, we don’t have that information.”
https://www.deseret.com/coronavirus/2022...t-possible
https://www.deseret.com/coronavirus/2022...t-possible