A new study has found that some people could develop multiple sclerosis (MS), if they catch the “kissing illness”.

Researchers at University College London (UCL), England, found that people who had mononucleosis as a child were more likely to develop MS later in life.

It was previously believed that people with a higher genetic risk of MS were more likely than others to develop serious monomyalgia if they were exposed. However, researchers have now reversed this correlation.

Researchers discovered that MS is most likely to develop if the condition is contracted in childhood or adolescence. This was around a decade after initial diagnosis.

Mono in the earliest years of adulthood was not associated with an increased risk for MS. 

A young person contracting mono, often dubbed 'kissing disease', can severely increase their likelihood of developing MS later in life (file photo)

A young person can contract mono, also known as ‘kissing illness’, which can greatly increase their chances of developing MS later in their lives (file photo).

Mono is a disease often transferred via saliva, earning it the 'kissing disease' moniker. It is especially common in teenagers

Mono is a common disease that can be transmitted via saliva. This gives it the moniker of ‘kissing diseases’. It is most common in teenagers.

Mononucleosis, a contagious disease, is often spread via saliva.

Many people, especially teens, contract the disease by kissing infected persons, which is why the ‘kissing illness’ moniker is used.  

For the study on MS, researchers collected medical data from over 2.5 million people.

MS can be linked to genetic factors. The team had to discover a way to control individuals’ genetic risk of developing MS.

They also wanted the possibility that the same factors which cause MS could also cause monomyalgia.

They used mono to compare the records of people who had been diagnosed with the disease to those who didn’t or who were affected at a different time.

“Siblings share a lot of their genetic makeup and have similar family lives. If one sibling develops [mono]The one goes on to develop MS, the other doesn’t. [mono]Scott Montgomery, UCL’s lead researcher and professor, said that if he doesn’t develop MS, it would suggest that it is glandular fever and not genetic predisposition that caused the MS.

Participants were divided into three age categories: participants aged ten or younger, 11-19 and 20-24. 

People who contracted mono were 0.16 percent of those who did not develop MS in the group below 10 years old, and 0.27% of those who did – an increase of 68 percent.

The 11-19 age group saw the greatest increase, with monomicropia accounting for 0.72 percent of those who did not develop MS, and 1.84 percent of those who did.

This is a sharp rise of 155 percent, which puts people who get the disease at greatest risk from 11 to 19.

Mono tends to diminish once someone turns 20.

Researchers discovered that MS was more common in people who were infected between ages 20 and 24. This is compared to 0.29 percent for those who developed it.

Although it is an increase, the team did not consider it significant enough to draw any conclusions.   

Researchers also discovered that MS progresses slowly. Most people don’t notice symptoms until they are 30 years old.

It could take over a decade for a person who contracts mono to later develop MS, giving doctors ample time to potentially treat a high risk person and prevent the worst effects of the disease

A person who has mono may take more than a decade to develop MS. This gives doctors plenty of time to possibly treat a high-risk person and prevent the worst.

Mono can trigger the condition. However, it could take more than a decade to feel the full impact. 

“[Mono]Montgomery wrote that MS could be triggered during teenage years because it can get into brain.

‘And the damage it causes to nerve cells may cause the immune system to start attacking a part of the nerves that insulates them – called the myelin sheath.

This is known as autoimmunity. It can cause nerve damage in the brain, which can get worse over time.

MS is a potentially crippling condition that attacks the nervous systems.

It causes the immune systems to attack nerve protective casing called the myelin sleeth and causes brains to miscommunicate with other parts of the body.

In severe cases, paralysis or immobilization could result.

The slow pace of the process can be beneficial as it allows for a large window of time in which a person who has mono and slowly develops MS can begin treatment. 

Montgomery wrote, “Fortunately, modern treatments are becoming more effective in slowing down this process.”