I don't think that OCD is as potentially upsetting to hear about as something else. I mean, it is not like telling someone they have bad breath or body odour.

My son exhibits the same tendencies. He is afraid of picking up bed bugs in public spaces too (although that is a fair worry these days as they are endemic). Add to the list of symptoms too that I observe him straightening things and I don't think he even realises he does it.

So, I actually did in fact bring it up myself recently and it went a good deal more smoothly than I anticipated. I simply said to him that I have been noticing things and has it occurred to him he might be OCD? His reaction? He actually said he was aware of it but couldn't help it. This led then to further discussion where he admitted to being embarrassed and bothered by it as it has reached the point that it now affects his daily life (ie. the decision to go places). We ended the discussion with an agreement that he start first with having a discussion with his family doctor who will determine if he can treat my son or refer him up the channel to someone who can.

It all went far more easily than I had anticipated. Remember what I said above; there are far worse things you could be broaching a discussion about.