Sterilizing immunity is the term you're looking for, and as far as I know the vaccines are still being studied to determine if it happens. It's very difficult

Sterilizing immunity is the term you're looking for, and as far as I know the vaccines are still being studied to determine if it happens. It's very difficult to determine right now because you need to very carefully control a studied person AND all of their contacts and people they interact with--you test all of those people daily and then can tell if people in the vaccine or placebo group have close contacts coming down with sickness more or less often (hinting at the presence or not of sterilizing immunity). The big trials for EUA of the major vaccines declined to do this kind of study because it takes longer and costs a LOT more to do that much testing across 60k people + all their contacts. It will also be more challenging going forward to do these kinds of studies because of the ethics. It will be hard to ethically justify keeping an arm of a trial unvaccinated as a placebo in the face of a very serious and very deadly virus which we have known good vaccines. There are some interesting things like crossover trials that apparently more of the current in research vaccines are trying.