Virus causing the kissing disease may also play a role in multiple sclerosis

Author: Anne Eck

Virus causing kissing disease may also play a role in MS
It has been long suspected that the exceedingly common virus that causes mono, the Epstein-Barr virus, may play a role in de development of multiple sclerosis. Affecting about 1 in 700 people in the Netherlands, this neurological illness has debilitating effects on its patients. A recent study following over ten million people over the span of 20 years proves that indeed, there is a strong link between the Epstein-Barr virus and multiple sclerosis.

Multiple sclerosis is an autoimmune disease that affects the central nervous system. In people suffering from multiple sclerosis the body’s immune system attacks the fatty insulating layer that surrounds nerves, leading to breakdown. This may result in pain, mobility, cognitive and eyesight problems.

What exactly triggers multiple sclerosis has not yet been discovered. An old hypothesis is that it is caused by a viral infection, with the Epstein-Barr virus being the main suspect. The virus mostly known for causing mono (the kissing disease) has infected about 90% of the population sometime throughout their life. After people are infected with the virus it hides within cells, where it will wait until the immune system is weakened before becoming active again.

To research whether this link actually exists, Dr. Alberto Ascherio from the Harvard T.H. Chan School of Public Health looked at blood samples of over 10 million people who were on active duty in the US between 1993 and 2013. Out of these 10 million, 801 people developed symptoms of multiple sclerosis. Samples taken before and after onset of the neurological illness were tested for various viruses. 

Out of the 801 people suffering from multiple sclerosis, 800 patients tested positive for the Epstein-Barr virus. It was also ruled out that other viruses causing mono, such as the closely related Cytomegalovirus, played a role in the development of the illness. From these results, the team calculated that people who are infected with the Epstein-Barr virus are 32 times more likely to develop multiple sclerosis throughout their lives. This may bode well for future prevention: Dr. Lawrence Steinman wrote a perspective on how targeting the virus may prevent it from affecting the brain.

Although a very large part of the population catches mono during their teen or young adult years, very few people actually develop multiple sclerosis. 90% of people have been infected by the Epstein-Barr virus during their lifetime, but multiple sclerosis does not affect 90% of the population. This means that more factors than just viral infection are necessary for the development of the disease. What exactly these factors are, however, is not yet fully understood.