Having infectious mononucleosis (often referred to as mono) caused by the Epstein-Barr virus is associated with an increased risk of developing multiple sclerosis (MS), according to a study published on April 1, 2026. Neurology® Open Accessthe official journal of the American Academy of Neurology.
Epstein-Barr virus is a very common herpesvirus that causes no symptoms in most people. However, if you get the virus as a teenager or adult, it can cause mononucleosis. Epstein-Barr virus is the most common cause of mono infections. This study does not prove that mono infections caused by Epstein-Barr virus cause MS. Just show the relevance.
“These results highlight the need for further research into ways to prevent Epstein-Barr virus infection,” said study author Jennifer L. St. Sober, Ph.D., of the Mayo Clinic in Rochester, Minnesota. “Preventing these infections could reduce the overall burden of multiple sclerosis. Multiple sclerosis is relatively rare, carries the risk of significant disability and expensive treatment, and typically develops in the prime of life when people are working and raising families.”
For the study, researchers looked at more than 20 years of medical records to find people who tested positive for Epstein-Barr virus infection and were diagnosed with infectious mononucleosis. Each of the 4,721 people the researchers identified was compared with three people of the same age and gender who did not have the mono-infected disease, or 14,163 people.
Those who had things were followed for an average of six years. People without possessions were followed for an average of eight years. During that time, 8 people (0.17%) with a history of mono developed MS. This equates to 2.25 cases per 10,000 person-years. Person-years represent both the number of people who participated in the study and the time each person spent in the study. In the no-thing group, 10 people developed MS (0.07%). This equates to 0.77 cases per 10,000 person-years.
The researchers then adjusted for other factors that may influence MS risk, such as race or ethnicity, smoking status, and whether participants had other conditions such as diabetes, depression, or substance use disorders. After adjustment, people with a history of mono infections were found to be three times more likely to develop MS than those without mono infections.
“Although mononucleosis is a relatively rare disease, developing strategies to prevent infection with the virus that causes this disease may help reduce the number of MS cases in the future,” Professor St Sauber said.
A limitation of this study is that participants were followed for an average of six to eight years, so it is possible that some people develop MS later in life.
This research was supported by ModernaTX, Inc., which is developing vaccines that target multiple Epstein-Barr virus-related conditions.
sauce:
American Academy of Neurology
Reference magazines:
https://www.neurology.org/doi/10.1212/WN9.0000000000000082
