You might be right, when co-workers have the flu I often feel it coming on for a day or so then it fades, I never get sick or cough or sneeze, just the initial flu like feeling as in “Oh no, here it comes” then nothing, so I think I am as immune as they are only without the shots (and all the mercury and Lord knows what else is in them). I’ve been exposed to the flu’s just as they have, no doubt about it.
This is exactly what happens to me. I feel like I'm getting sick and then, nothing. Maybe they should study our genes!