They found 56, 681 MS cases and 14, 621 cases of glandular fever, which is caused by the Epstein-Barr virus.

BBC: Virus and low sunlight 'raises multiple sclerosis risk'

Scientists believe that Mohammed's cancer is caused by the Epstein-Barr virus, which is better known for causing glandular fever.

BBC: Mohammed

However when they combined the effect of sunlight and glandular fever, 72% of the variation in MS cases could be explained.

BBC: Virus and low sunlight 'raises multiple sclerosis risk'

There were fears that the Briton was suffering from glandular fever, something that has hit both Roger Federer and Mario Ancic in recent years.

BBC: Murray returns with doubles win

The 27-year-old world number two was diagnosed with glandular fever at the start of the year and admitted he has been playing catch up ever since.

BBC: Tired Federer opts to take break