MEDICAL RESEARCH

SCOTTISH doctors believe they have found the cause of Multiple Sclerosis (MS), paving the way for a vaccine against the devastating condition.

A landmark paper suggests MS develops following two separate common infections, which cause the body to attack itself.

Other factors, such as genetics and lack of sunlight, may also play a role, which explains why MS is more common in certain areas such as the North of Scotland.

But doctors behind the latest discovery believe the development of a vaccine against a common virus may hold the key in future prevention of the disease. The research was published by doctors from the University of Glasgow and Harvard University in the United States.

There are 11,000 Scots with MS, making the disease more common than in most other countries.

The neurological condition is triggered when the immune system, which normally fights infection, attacks nerves, causing pain, fatigue, vision problems and spasms.

But what causes the body to begin attacking itself has never been identified, despite more than 100 years of research.

It has been suggested the disease could be caused by lack of sunlight as it is more common in northern countries.

The latest research claims two common infections – firstly threadworms followed by the Epstein-Barr virus – may be the trigger. The scientists believe MS is a “rare complication” of the body’s response to the infections.

Professor John Paul Leach, consultant neurologist at the University of Glasgow, said: “MS is a condition where the body produces antibodies against itself for reasons that have never been understood and goes against its own nervous system.

“It is odd that we have never found out why some people are more prone than others.

“There is already some evidence that exposure to the Epstein-Barr virus makes it more likely someone will develop MS, but this does not offer the full explanation of why people develop this reaction.

“MS may be the result of not one but two infections in the right order.”

The research was led by Dr Patrick Kearns of the Chan School of Public Health at Harvard, who developed his theory while studying at the University of Glasgow.

Although keen to point out their hypothesis is only a theory, they now plan further research.

In MS, the immune system attacks the layer that surrounds and protects the nerves which damages them, meaning messages become slowed or disrupted.

Threadworms affect around one sixth of the world’s population and are a parasitic infection affecting the gut, common in children.

The Epstein-Barr virus is one of the most common viruses in humans and is the cause of glandular fever, although many people only suffer mild symptoms.

Dr Kearns said: “MS is a terrible condition but there is a fascinating aspect about it which is that its distribution around the world has been really well studied, so it’s easy to compare rates between regions.

“It also affects people when they are young, and rates are increasing, which means some aspect of the environment has to be changing that’s driving the disease.

“Some evidence has found high rates of MS in areas where there were military troops stationed in the Second World War, such as the Faroe Islands and Shetland.

“I believe the missing link may be threadworm infection. This is a very common condition in children and is also common in soldiers living in barracks. In areas where soldiers were billeted during the war it would have spread to local populations.

“There is already a strong and undeniable link between the Epstein-Barr virus and MS. I believe that what may be causing MS is a rare, late complication of exposure to these two infections.

“It may be a good idea for public health officials to treat worms at a population level. But the real benefit would be developing better tools to target the Epstein-Barr virus with a vaccine or drugs.”

Factors such as lack of sunlight or vitamin D have previously been suggested as triggers for MS.

But Dr Kearns believes the evidence for these is “not very strong” and does not fully explain the differences in MS rates around the world. However, he said some people may be more susceptible than others due to genetic factors.

There is currently no cure for the condition, but some treatments can slow its progress.

The research was first published in the journal Multiple Sclerosis and Related Disorders.

Dr Sorrel Bickley, head of biomedical research at the MS Society, said: “This study puts forward an interesting idea and we look forward to seeing how this could be proven or disproven.

“MS is unpredictable and different for everyone and we urge anyone concerned about symptoms to speak to their GP.”

 

MULTIPLE Sclerosis is a neurological disease that can affect the brain and spinal cord.

The condition’s symptoms are wide-ranging and can include problems with vision, arm or leg movements, sensation or balance.

In some cases, the disease can be mild but in others it can cause serious disability.

Average life expectancy is reduced in people with MS.

The immune system attacks the layer that surrounds and protects the nerves – the myelin sheath. This then damages and scars the sheath, and potentially the underlying nerves, meaning that messages travelling along them can become slowed or disrupted.

This can cause a range of symptoms including fatigue, difficulty walking, vision problems, numbness or tingling in different parts of the body and muscle stiffness and spasms.

Symptoms may come and go in phases, known as relapsing remitting MS, or get steadily worse over time.

Roughly between two and three women have MS for every man with the condition. In Scotland the rate is about 209 MS patients per 100,000 population compared to 164 per 100,000 in England.