For a long time it has been suspected that the common Epstein-Barr virus (EBV) can trigger multiple sclerosis.
A A new study by scientists from Harvard University in the United States provides the most solid evidence to date that it actually plays a key role in triggering this disease.
An investigation carried out with more of 10 millions of US military recruits showed that virtually all cases of multiple sclerosis are preceded by an infection with the virus.
“Our group and others have investigated for years the hypothesis of that EBV causes multiple sclerosis, but this is the first study to provide convincing evidence of causality ,” Italian researcher Alberto Ascherio, professor of epidemiology and nutrition at the school to Public Health TH Chan of Harvard and lead author of the study.
“This is a big step because it suggests that most cases of multiple sclerosis could be prevented by stopping EBV infection , and that targeting EBV could lead to the discovery of a cure for multiple sclerosis.”
The study, after a 2-decade investigation, was published online on 13 of January in the Science magazine.
What are EBV and multiple sclerosis
Multiple sclerosis, which affects 2.8 million people in the world, is a chronic inflammatory disease of the central nervous system in which the immune system attacks the myelin sheaths that protect neurons in the brain and spinal cord. When this nerve sheath is damaged, nerve impulses slow down or stop.
This disease can cause a wide range of potential symptoms, including problems with vision, movement of the arms, or legs, sensation, or balance.
In multiple sclerosis there is damage to the myelin sheaths that protect neurons in the brain and spinal cord. (Photo: GETTY IMAGES)It is a lifelong condition that can cause serious disability, although sometimes it can be mild.
Its cause is unknown, but one of the main suspects is EBV, a type of herpes virus that infects approximately 95% of adults.
The Epstein-Barr virus is transmitted mainly through saliva, for example, by kissing or drink from the same glass.
This virus is the cause of mononucleosis, also known as glandular fever or “kissing disease”, and establishes a latent infection of for life in the host.
What did the study consist of
The difficulty in establishing a causal relationship between the Epstein-Barr virus and multiple sclerosis is that e This virus infects approximately 24 % of the population.
Multiple sclerosis, on the other hand, is relatively rare and the onset of symptoms begins about 10 years after Epstein-Barr virus infection, according to the TH Chan School of Public Health said in a statement.
Studies of large numbers of individuals are required to establish whether people who have not been infected with the virus are less likely to develop multiple sclerosis .
To determine the connection between the virus and multiple sclerosis, researchers analyzed serum samples taken every two years from recruits.
In this way they determined the Epstein-Bar virus status of the recruits at the time of the first sample and the relationship between virus infection and the onset of multiple sclerosis during the period of active duty.
Serum levels of neurofilament light chain, a biomarker of nerve degeneration typical of multiple sclerosis, only increased after EBV infection.
These results “cannot be explained by any known risk factor for multiple sclerosis and suggest that EBV is the main cause” of this disease, according to the researchers.