You would expect a seasonal decline to begin to grassroot next month mate and continue in to April and go on, might be a bit different this year with the new variants. The vaccine will help to double down, but be a moving target so we should see the trend we are seeing in Europe now of falling infection rates. An acid test may be a gradual opening up. We also might see a climb in the Southern hemisphere that will tell us a bit. If there is a way to distinguish I don’t know it, you would need to study each persons vaccine profile, but we can compare data from last year to this in case incidence and study the variance.
What governments won’t tell you is getting jabs into peoples arms by Oct at the latest is critical or we are heading into another difficult winter. We are expecting a really difficult time with Flu next year, as literally there has been none this year around the world and we have very little sample of strain evolution to update next years flu vaccine. The other thing to keep an eye on is the circular nature of the vaccine rollout, it’s not a once off. For instance I got double dosed in Jan. Come next flu season, do I need to be revaccinated etc. You might be better off getting vaccinated altogether during the summer to have protection next winter and a slow roll out might be advantageous. The clever play now is planning the next roll out and procurement of vaccines.