Madrid
Updated:
Keep
The multiple sclerosis (EM), a degenerative disease, might have an infectious origin. The Epstein-Barr virus(WEB), known as the human herpes virus or as the cause of the mononucleosis The ‘kiss sickness‘, is, according to a study published this Thursday in’ Science ‘, the cause of multiple sclerosis, a progressive disease for which there is no definitive cure and that affects2.8 million people worldwide.
A team of researchers from the
Chan School of Public Health at Harvard University
(EE.UU.) might have finally found the trigger for this disease, something that has been investigated for many years. “For years our group and others have investigated the hypothesis that EBV causes MS, but this is the first study to provide compelling evidence of causality,” he says. Alberto Ascherio, lead author of the study.
According to Ascherio, “This is a big step because it suggests that most cases of MS might be prevented by stopping EBV infection.” In addition, he stresses that by focusing on this virus “we might finally identify a cure for MS.”
MS is a chronic autoimmune disease that works by damaging myelin in the body of those affected, a fatty material that insulates the nerves and allows them to transmit electrical impulses to and from the brain quickly. The body’s own tissue is treated as a foreign body, and the onset of the disease is often triggered by a combination of genetic and environmental factors.
It is estimated that it affects more than 47,000 people in Spain and it is the most common chronic neurological disease in young adults between the ages of 20 and 40 in Europe and North America, especially in women.
Although its cause is unknown, one of the main suspects has always been EBV, a herpes virus that can cause infectious mononucleosis and generates a latent infection for life in the host.
Until now, it has been difficult to establish a causal relationship between the virus and the disease because EBV infects approximately 95% of adults and the onset of MS symptoms begins regarding 10 years following EBV infection.
To determine the connection between EBV and MS, the researchers conducted a study of more than 10 million young adults in the US military and identified 955 who were diagnosed with MS during their tour of active duty.
The researchers analyzed serum samples taken every two years by the military and determined the EBV status of the soldiers at the time of the first sample and the relationship between EBV infection and the occurrence of MS during the period of active duty.
Thus, they saw that in this group the risk of MS increased 32 times following EBV infection, but was not altered following infection with other viruses.
The analyzes showed that serum neurofilament light chain levels, a biomarker of nerve degeneration typical of MS, increased only following EBV infection.
The findings, they write, cannot be explained by any other known risk factors for MS and suggest that EBV is the leading cause of multiple sclerosis.
Ascherio suspects that the delay between EBV infection and the onset of MS may be due, on the one hand, to the fact that the symptoms of the disease were not detected during the early stages and, on the other, to the relationship in evolution between EBV and the host’s immune system, which is repeatedly stimulated each time the latent virus reactivates.
Although there is currently no way to effectively prevent or treat EBV infection, he concludes, “an EBV vaccine or targeting the virus with EBV-specific antiviral drugs might, we think, prevent or cure MS.”
These results mean that there may be new opportunities for treating MS, ask William H. Robinson and Lawrence Steinman of the
Stanford University (USA) in a commentary published in Science.
“Most of us are infected with EBV, but only a small fraction develop MS,” they write. Therefore, they point out that there are “other factors, such as susceptibility, are important in the pathogenesis of MS.”
Therefore, they point out that, due to these elements implicated in the pathogenesis of MS, “EBV infection is likely to be” necessary, but not sufficient, to trigger the development of MS. “
EBV infection, they claim, is the initial pathogenic step in MS, but other factors must be activated for full pathophysiology.
Antivirals that target EBV may provide effective therapy, they wonder, especially when given early.
And they conclude: “Now that the initial trigger of MS has been identified, perhaps it might be eradicated.”
.
