I’ve never heard that one about Lyme disease, although they certainly have similar symptoms, so it is a differential diagnosis.
I think I was tested for it as part of the investigations - I was tested for over 100 things (yes, that was a lot of vials of blood, but thankfully not a separate one for every test). I didn’t even know the names of most of them, but I think Lyme disease was among them. I know HIV was also on the list - the neuro went out of his way to check my permission for that one - I suppose because the possible implications are such that it’s a bit off to test people without their knowledge and express consent.
I was diagnosed privately, so I don’t know if they do any extra investigations the NHS normally wouldn’t, but as I had the exact same neuro privately that I later transferred to on the NHS, and he seems a pretty ethical kind of guy, I very much doubt he would discriminate between private and NHS patients by ordering different tests. I’m fairly certain the battery of tests he ordered were the same ones he always does, whether it’s private or not - having said that, he may be a bit of a stickler for thoroughness, and not ALL neuros may check everything he wanted to.
From one of Whammel’s links, about 90% of the population have EBV antibodies anyway, which indicates exposure is the norm, rather than the exception. So you’d expect the vast majority of PwMS to have been exposed too.
With something nearly everyone’s been exposed to, it’s very hard to prove it was or wasn’t a causal factor. What we really need is something that’s extremely rare in people who don’t have MS, but high in those who do. Then we’d really have a smoking gun.
But something 90% of people have anyway (but the vast majority don’t get MS) doesn’t make a black-and-white case. If it was EBV, it would still mean there had to be something different about those people who reacted by developing MS, compared to the vast majority who didn’t. So then we’d just be shifting the mystery to: “Why did they react in an abnormal way to something nearly everybody’s had?”