From TSN – We don’t yet know if a booster shot will be necessary for the COVID vaccine, but a study out of Houston is trying to determine which booster would be best. There are 150 fully vaccinated participants getting a Moderna booster shot. A third of the study group received Moderna, a third with Pfizer and Johnson and Johnson. They are mixing and matching vaccines and looking at which boosters are safe and effective. Next, they’ll do a study with a J&J and later Pfizer.