Evidence found linking herpes virus to MS

Research suggests people with Epstein-barr virus are 32 times more likely to develop incurable disease

THE virus that causes herpes is likely to be the main cause of multiple sclerosis (MS), a groundbreaking study has suggested.

Harvard academics found that the Epstein-barr virus (EBV) — one of the most common viruses in the world — increases the chance of multiple sclerosis 32-fold.

Scientists have long speculated that the virus may be linked to the condition, but have been unable to provide any evidence to back this up.

“This is the first study providing compelling evidence of causality,” said Alberto Ascherio, professor of epidemiology and nutrition at Harvard T.H. Chan School of Public Health and senior author of the study.

“This is a big step because it suggests that most MS cases could be prevented by stopping EBV infection, and that targeting EBV could lead to the discovery of a cure for MS.”

The Us-based researchers studied the medical records of more than 10 million people enlisted in the US military, of which 955 developed multiple sclerosis during their period of service.

Blood samples taken twice a year by the military were analysed by the researchers to determine if the person had the virus, and this was cross-referenced against a later MS diagnosis.

A protein and biomarker for nerve degeneration called NFL only increased in those who had been infected with the virus, the researchers write in their study, published in the journal Science.

There is currently no cure for MS, which is a relatively rare condition that affects about 110,000 people in the UK. The National Multiple Sclerosis Society says the risk of developing MS in the general population is about one in 1,000.

MS is a chronic inflammatory disease of the central nervous system that attacks the myelin sheaths protecting neurons in the brain and spinal cord, and its cause remains elusive. The symptoms are unpredictable and can range from physical disabilities, such as mobility problems, to mental health conditions, such as depression.

Many people with MS report feeling an overwhelming sense of exhaustion, making simple tasks a struggle. In about a quarter of cases, the first noticeable symptom is a problem with one of the patient’s eyes, including colour blindness and double vision.

In contrast, Epstein-barr virus infection is astoundingly common, and can be found in about 95 per cent of people.

EBV infection can leave people feeling tired and is also known as mono or herpes. After a person contracts the pathogen, it stays in their system forever, often without any symptoms but occasionally reactivating.

Prof Daniel Davis, professor of immunology at Manchester University, said: “Well over nine in 10 people are infected with this virus worldwide, usually in childhood, and only very rarely does a problem arise.

“Crucially, we do not know why only a small fraction of people infected with this virus develop a problem.”