The Epstein-Barr virus has long been suspected of playing a role in development of MS. It’s a connection that’s hard to prove because just about everybody gets infected with Epstein-Barr, usually as kids or young adults -- but only a tiny fraction develop MS. … Thursday, Harvard researchers reported one of the largest studies yet to back the Epstein-Barr theory. They tracked blood samples stored from more than 10 million people in the U.S. military and found the risk of MS increased 32-fold following Epstein-Barr infection.