Multiple sclerosis, a chronic disease of the central nervous system, could be caused by infection from the Epstein-Barr virus, a common herpes virus, according to a new study.
The research, published in the journal Science on Thursday, was led by a team from Harvard University’s T.H. Chan School of Public Health. The researchers studied more than 10 million young adults on active duty in the military and identified 955 who were diagnosed with MS during their service.
The team analyzed samples taken from the military members every other year, examining whether they had the Epstein-Barr virus and the relationship between an infection and onset of MS.
Among those studied in the research, the risk of developing MS increased 32-fold after infection with the Epstein-Barr virus.
The team also found that levels of a “biomarker of the nerve degeneration typical in MS” increased only after individuals had an Epstein-Barr virus infection, according to a news release from Harvard University.
“The hypothesis that (Epstein-Barr virus) causes MS has been investigated by our group and others for several years, but this is the first study providing compelling evidence of causality,” Alberto Ascherio, professor of epidemiology and nutrition at Harvard Chan School and senior author of the study, said in the news release.
When an individual has MS, their immune system attacks their central nervous system, according to the National Multiple Sclerosis Society. The disease can disrupt the flow of information within the brain and body and cause permanent damage.
MS can be diagnosed at any age, but its onset usually occurs when a person is between 20 and 40 years old. If a person’s parent or sibling has had the disease, they are also at a higher risk of developing it, according to the Mayo Clinic.
Epstein-Barr virus is one of the most common human viruses, according to the U.S. Centers for Disease Control and Prevention. It primarily spready through bodily fluids such as saliva and can cause infectious mononucleosis, also called mono.
The Harvard team explained that the Epstein-Barr virus has been “one of the top suspects” as researchers have searched for a cause for MS. But they noted that linking the virus and MS has been difficult because the virus “infects approximately 95% of adults” while MS is “a relatively rare disease, and the onset of MS symptoms begins about ten years after (Epstein-Barr virus) infection.”
Ascherio said in the news release that the research marks a "big step" because it "suggests that most MS cases could be prevented by stopping (Epstein-Barr virus) infection, and that targeting (Epstein-Barr virus) could lead to the discovery of a cure for MS.”
“Currently there is no way to effectively prevent or treat (Epstein-Barr virus) infection, but an (Epstein-Barr virus) vaccine or targeting the virus with (Epstein-Barr virus)-specific antiviral drugs could ultimately prevent or cure MS,” he said.
Funding for the study came from the National Institute of Neurological Disorders and Stroke, National Institutes of Health, the National Multiple Sclerosis Society, the German Research Foundation and the Howard Hughes Medical Institute.
This article originally appeared on USA TODAY: Epstein-Barr virus could cause multiple sclerosis, Harvard study shows