[chub500]

Not sure why this is being downvoted. I think your logic is sound. Typically vaccinations don't work this way though. AFAIK contagion is proportional to viral load which is inversely proportional to immune response (via some complex function over time from initial infection).

[AndrewBissell]

I certainly agree that vaccinations typically don't work this way, which is why I find it very odd that there seems to be an effort to quickly handwave away these uncertainties with "well all vaccines are like this."