Multiple sclerosis news

Low levels of sunlight combined with a common viral infection may increase a person’s chances of developing multiple sclerosis (MS), a study has found.

Past research suggests that vitamin D deficiency may be a risk factor for the autoimmune disease.

Vitamin D is produced by the body when exposed to sunlight, and MS is generally more common in countries at higher latitudes, farther away from the equator. However, considerable variation within countries also exists; Scotland has particularly high rates of MS compared to other parts of the UK.

Infection with Epstein Barr Virus, which can cause glandular fever, has also been suggested as a risk factor for MS.

Multiple sclerosis

“Since the disease has been linked to environmental factors such as low levels of sun exposure and a history of infectious mononucleosis, we wanted to see whether the two together would help explain the variance in the disease across the United Kingdom,” said Professor George Ebers, of Oxford University, who led the study.

In the study, researchers examined data on all hospital admissions in England between 1998 and 2005. They identified 56,681 cases of MS and 14,621 cases of glandular fever.

They also used NASA data to calculate the intensity of ultraviolet radiation in different parts of England.

Sunlight levels alone accounted for 61 per cent of the difference in MS rates across the country.

But taken together, sunlight levels and a history of glandular fever explained 72 per cent of the difference in MS rates across the UK, the study found.

Professor Ebers said: “It’s possible that vitamin D deficiency may lead to an abnormal response to the Epstein-Barr virus.

“More research should be done on whether increasing UVB exposure or using vitamin D supplements and possible treatments or vaccines for the Epstein-Barr virus could lead to fewer cases of MS.”

The findings are published in the journal Neurology.