Researchers in a study published in Science have suggested that the Epstein-Barr virus (EBV) may be a possible cause multiple sclerosis (MS).
Kjetil Bjornevik, M.D., Ph.D., from the Harvard T. H. Chan School of Public Health in Boston, and colleagues examined the association between the prevalence of EBV and MS in a cohort of more than 10 million young adults on active duty in the U.S. military. A total of 955 incident MS cases were documented during the periods of service. EBV infection status was assessed in 801 MS cases and 1,566 controls.
The researchers found that only one MS case occurred in an EBV-negative sample (hazard ratio for MS comparing EBV-positive versus negative, 26.5). Thirty-five MS cases and 107 controls were EBV-negative at baseline.
During follow-up, all but one of the MS cases became infected with EBV and all seroconverted before MS onset. The hazard ratio was 32.4 for MS comparing EBV seroconversion versus persistent EBV seronegativity.
Antibodies against cytomegalovirus (CMV) were measured as a negative control; seroconversion for CMV occurred at a similar rate in those who later developed MS and those who did not.
To examine the temporal relation between EBV and MS, serum concentrations of neurofilament light chain (sNFL) were assessed. Individuals who were EBV-negative at baseline and went on to develop MS had sNFL levels that were similar to those of non-MS controls at the time of EBV infection, but levels increased thereafter.
“The extremely low MS risk in EBV-negative individuals suggests that by far most MS cases are caused by EBV and could thus potentially be prevented by a suitable vaccine,” the authors wrote.
REFERENCE: Bjornevik et al: Longitudinal analysis reveals high prevalence of Epstein-Barr virus associated with multiple sclerosis; https://www.science.org/doi/10.1126/science.abj8222