Does anyone know how long after you get the shot you are protected? My husband has congestive heart failure complete with pacemaker/defibrillator and he was supposed to get his flu shot before we leave for our cruise next week and he hasn't done it yet. Someone told me they thought it was too late to protect him on the cruise now. I was hoping some of our medical personnel
could tell me if he should go ahead & get it before we leave now or wait until we get back?