Multiple sclerosis is an autoimmune disease of the central nervous system (brain and spinal cord) characterized by destruction of the myelin sheaths, protective sheaths of nerve fibers that play a key role in the spread of nerve impulses. Its origin remains unknown, although several hypotheses are advanced.
One of them is infection with the Epstein-Barr virus (EBV), a mononucleosis virus, which survives latently in the body. In a new study, published on January 13, 2022 in the journal Science (Source 1), researchers support this link between EBV and the onset of multiple sclerosis (MS).
“The hypothesis that EBV causes MS has been studied by our group and others for several years, but this is the first study providing convincing evidence of causation”, Commented Alberto Ascherio, professor of epidemiology and nutrition at Harvard Chan School and lead author of the study, in a statement (Source 2). “This is a big step because it suggests that most cases of MS could be prevented by stopping the EBV infection, and that targeting EBV could lead to the discovery of a cure for MS.“, he added.
The team here followed more than 10 million young adults serving in the U.S. military, and identified 655 people diagnosed with multiple sclerosis during their years of service. Serum samples were taken every two years, and soldiers’ status with EBV infection was noted.
The data compared, it turned out that the risk of MS increased 32-fold after infection with EBV, but remained unchanged after other viral infections. As for the serum levels of a biomarker of nerve degeneration observed in MS, they did not increase until after infection with the Epstein-Barr virus. Results that “cannot be explained by any known risk factor for MS and suggests that EBV is the leading cause of MS”, Say the researchers.
The Epstein-Barr virus could cause multiple sclerosis by the immune stimulation it induces, which occurs each time the latent virus reactivates. This avenue therefore deserves to be further explored, because an EBV vaccine or an effective antiviral treatment could help prevent or even cure multiple sclerosis.