Yep I'm one of them. Lived in the UK in the early 80's as a child. Gave blood for the first time when I was in college in the 90's to the Red Cross here in the US, and they mailed me back saying to never give blood again but didn't specify a reason. It wasn't until a few years later that I found out why. And the fact I might have a prion disease lurking in my blood sometimes terrifies me.

I don't think it's a concern any more. The trajectory of cases that should have occurred if CJD was widespread in the community, never happened. One consequence of this is the blood donation ban has been lifted in most countries, I think.

Is there a blood test for that?

I don't think so. I believe it was a screening question. Which was odd since they allowed me to give blood at that time.

Well they got your sample for testing going forward.