Inflammation outside the brain - such as that caused by flus and colds - can make  multiple sclerosis worse, researchers at the University of Southampton have found.

The study, led by scientists from the university and University Hospital Southampton, suggested that inflammation is linked with the loss of nerve cells in the spinal cord, causing MS to progress.

MS is caused by the immune system mistakenly attacking the nerves in the brain and spinal cord.

Over time, this can lead to the loss of nerves, causing MS to worsen.

More than 150,000 people live with the condition in the UK, with 135 diagnosed each week.

The Systemic Inflammation in Multiple Sclerosis (SIMS) study, funded by the Multiple Sclerosis Society of Great Britain, followed 50 people living with “progressive” forms of the condition for two and a half years.

The researchers measured the extent of inflammation in the body by looking at a weekly urine sample from participants.

They said the study, highlighted the need for people with MS to seek help early on to minimise infections.

Professor Ian Galea, a neurologist and lead researcher on the study, said: “The results of this study suggest it is important for people with MS to minimise inflammation where they can.

“This includes receiving all recommended vaccinations and seeking prompt attention for bladder infections.

“Following a healthy lifestyle could also be beneficial, as factors like smoking, alcohol and obesity are linked to inflammation.”

One of the study’s participants, Richard Humpston from Portsmouth, was diagnosed with primary progressive MS in 2014.

Mr Humpston, 43, now medically retired having previously worked within the NHS, said: “I participated in the study, which meant freezing my urine every week and going into hospital for various tests and check-ups.

“I was told afterwards that there was some evidence that I had urine infections during the study.

“The results of this trial have highlighted how vital it is for me to stay hydrated to avoid this type of infection in future.

“And it also makes me realise how important it is to know the signs and symptoms of having a UTI, and to get help as soon as possible for any infection.”