His claim is debatable, and would never be considered fact by anyone in a serious setting. But seriously, I think you should look into getting tested.

His claim? His opinion. That's how your evasive, you dismissed it as opinion when it could be very well fact.

Speaking of evasive

All personal questions you can point at yourself and maybe in some kind of respectful tone, they will be met with a response, instead of ignoring the ad hominem and strawmen I could simply point them out.