Just to throw in my thoughts.....
When I first started my airline job, when getting home before doing anything I would go and wash my hands. After one wash with soap, the water would run away black, after the second, a more translucent grey, and finally after the third wash, it would run clear again.
After a couple of months of constant sniffles and partially-blocked nostrils, I wondered if I was picking up germs from work. So I decided to invest in a couple of microphone muffs and ear-pad sock things, as well as stocking up on Dettol anti-bacterial wipes from my local supermarket.
My pre-flight routine now is to use the wipes on any surface in the flight-deck where I'm likely to be toucing. EG, control column, thrust levers, flap selector, etc. And the checklist gets a wipe over too! I also use it on the headset before putting on my mic and ear-seal covers.
Result now is less sniffles and less blocked nostrils, and the water runs clean after only two washes..... Oh, and several strange looks from Captains questioning me on whether I have Compulsive Obsessive Disorder. To which my response is, "Well take a look at the filth down your side then!"
I don't know if my routine makes a difference, but at least it gives a slight peace of mind!
Cheers,
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