This isn’t good news for anyone who’s had a bad bout of mono. From Past Viral Infection Linked to Multiple Sclerosis:
New study findings provide further evidence that infection with Epstein-Barr virus, which can cause mononucleosis, may increase the risk of developing multiple sclerosis (MS) later in life.Investigators discovered that people with the highest levels of antibodies linked to Epstein-Barr — possibly indicating a history of severe infection — were more than thirty times as likely to develop MS later in life than those with the fewest antibodies.
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Epstein-Barr is an extremely common type of herpes virus, with more than 90 percent of the population in countries like the U.S. and U.K. estimated to have been infected at some point.