Epstein-Barr virus (EBV), also known as human herpesvirus 4, and it’s a member of the herpes virus family. It is one of the most common human viruses. EBV is found all over the world. EBV spreads most commonly through bodily fluids, primarily saliva and have been known to cause infectious mononucleosis, also called mono, or the kissing diseases and other illnesses.
The researchers examined the relationship between Epstein-Barr virus infection and MS in a cohort of more than 10 million US military service members by analyzing serum samples and medical data, discovering that EBV infections increased the odds of an MS diagnosis during their service by more than 32-fold. There were no such increases in the likelihood of other viral infections.
When the researchers looked back at samples from the cohort members who were later diagnosed with MS, they discovered that a predictor for neurodegeneration became increased only after EBV was detected in their blood.
The study is regarded as the first work providing convincing proof of causality. MS cases could now be prevented by stopping EBV infection hence targeting EBV could lead to the discovery of a cure for MS as indicated by Alberto Ascherio Lead author at Harvard T. H. Chan School of Public Health.
According to STAT, MS is characterized by brain scarring as a result of chronic autoimmune inflammation that causes demyelination of neurons. What what causes the immune system to initiate this self-directed onslaught has remained a mystery, while viruses have long been suspected as a possible cause. Herpesviruses, in particular, were identified early on as main suspects due to their proclivity for chronic infections. None of the numerous investigations tying herpesvirus to MS, however, could give conclusive proof that infections were the cause of the disease.
Because of the timing of both conditions, conclusively tying Epstein-Barr to MS has proven particularly difficult. According to the Gazette, EBV infections commonly occur in childhood or young adulthood, around a decade before MS symptoms develop. The Department of Defense Serum Repository, a trove of roughly 62 million serum samples collected from more over 10 million US service members every few years during their tenure in the military, along with medical information about the serum donors, allowed the researchers to overcome this hurdle, according to the researchers.
The researchers were able to delve deeper into the timing of EBV infection and MS progression by utilizing the repository’s temporal resolution. Aside from discovering a link between MS diagnoses and prior EBV infection, the researchers discovered that increased serum levels of neurofilament light chain (NfL), a neurodegeneration biomarker that previous research tends to suggest rises a few years before MS symptoms appear, occurred only after EBV antibodies rose as well.
“Not only were the soldiers not diagnosed with MS at the start of the study, but their NfL levels were also negligible, so they presumably didn’t have a case of MS smoldering under the radar,” neurologist Michael Wilson of the University of California, San Francisco, tells STAT, lending credence to the idea of causation.
Some experts are skeptical that the virus is directly responsible for MS.
According to the-scientist.com, some experts believe that the immune response to the virus, rather than the virus itself, may be to blame, noting that MS patients have overactive immune systems in general. The authors attempted to rule out this possibility by comparing EBV infection to cytomegalovirus infection, another common viral infection. They discovered that increases in serum levels of cytomegalovirus antibodies did not predict NfL levels. However, Reder cautions that cytomegalovirus may be an unsuitable comparison because previous research has found infections with it to be oddly protective against MS.
Although EBV is common it’s yet to be explained why MS is so rare as approximately 95 percent of adults have been infected by the virus, according to the Gazette, but MS is seen in less than half a percent. In general, the study “leaves many questions about pathogenesis unanswered,” writes Corboy.
Nonetheless, the study remained the most convincing data we’ve had for a causal association, as agreed by Michael David Kornberg, a multiple sclerosis specialist at Johns Hopkins University, tells the Times.
Dr. P. Edem Nukunu, MD[HM], BSc.Dentl/Psychotherapist Edem has worked with Noguchi Memorial Institute for Medical Research (NMIMR) and had served as volunteer Scientist for SARS-CoV-2 at NMIMR. Currently he is the Medical director/Physician at MedNova Clinics. He is also a member of the Medical Journalists’ Association – Ghana and a member of the World Federation of Science Journalists as well as a member of the Global Emerging-Pathogen Treatment (GET) Consortium-(PLUS Faculty). Reach out for him via correspondent e-mail: penukunu@medhealth.info
