I've never had Epstein-Barr, unless its one of those viruses you can have without knowing, and I've never had Mono. I agree with Kitty that there are probably lots of causes. I think there has to be the perfect mixture of things (viruses, environment, whatever) to make MS happen. I also believe that MS is probably a dozen different diseases that we don't know about yet. But I'm confident that we'll have some answers to something in the next decade or so--causes, hopefully.