The link between Epstein-Barr virus and multiple sclerosis has been suggested for some time but this publication in Science really underlines the importance.

"Longitudinal analysis reveals high prevalence of Epstein-Barr virus associated with multiple sclerosis" DOI

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system of unknown etiology. We tested the hypothesis that MS is caused by Epstein-Barr virus (EBV) in a cohort comprising more than 10 million young adults on active duty in the US military, 955 of whom were diagnosed with MS during their period of service. Risk of MS increased 32-fold after infection with EBV but was not increased after infection with other viruses, including the similarly transmitted cytomegalovirus. Serum levels of neurofilament light chain, a biomarker of neuroaxonal degeneration, increased only after EBV seroconversion. These findings cannot be explained by any known risk factor for MS and suggest EBV as the leading cause of MS.

Almost everyone gets exposed to EBV (Human gammaherpesvirus 4) and it is the cause of glandular fever (aka infectious mononucleosis), after you get an EBV infection, the virus becomes latent (inactive) in your body. In some cases, the virus may reactivate. EBV infects the B cells of the immune system and epithelial cells. Once EBV's initial lytic infection is brought under control, EBV latency persists in the individual's B cells for the rest of their life.

EBV has been implicated in a variety of other diseases including various cancers.

This publication will certainly added increased interest in the Moderna the Phase I Eclipse clinical trial of its Epstein-Barr Virus (EBV) vaccine candidate, mRNA-1189. https://www.clinicaltrialsarena.com/news/moderna-ebv-vaccine-trial/.