As an FA I'm constantly sick- colds and everything else - all the time. It's a miracle that I make it in to work at all.
Actually, that's the opposite of the truth, but I could probably use it to fill out a magazine column if I had to. If Mr. Pink's theory is correct, you might reasonably expect that those who spend their working lives in aircraft cabins might be the worst affected? - They're not.
The Air Filters in aircraft cabins are
HEPA standard: You're not at risk as a result of recirculated bugs and germs, but you are if you are sitting next to somebody with a cold - just as on a bus, metro etc.
Antiseptic cream doesn't (and can't) cure or prevent the common cold: Moist nasal passages however, do help lots of good things to happen, which is why I ram vaseline up my schnoz when going on crew rest - stops tubes drying out while sleeping (or trying to). Oh, the glamour!