Sas
Contributor
The likelihood of transmitting hepatitis (which is essentially not carried in saliva) or AIDS (which is not carried in saliva) by sharing a regulator is lower than your likelihood of getting killed in an auto accident on the way to the dive site. The likelihood of picking up a respiratory virus (which IS carried in mucus) is somewhat higher, although again, as the reg is passed from one person to another, it's being rinsed to some extent. I would not be happy sharing a regulator with someone with cold sores, though. That's a fairly easily transmitted virus which is present in significant quantities in tissue that is in contact with the regulator, and the biggest problem is that it's a persistent virus that you may never completely clear.
If I had a cold sore (which I luckily have never had) I would politely decline to participate in training activities that involve sharing a reg until the lesions were healed.
That is interesting to know. I definitely won't be too polite in the future if I end up buddied with someone with cold sores!