Image copyright Ashleigh White Image caption Ashleigh White, from Barnsley, and her son, Noah.

Ashleigh White's son Noah became seriously ill with neonatal herpes after being infected with HSV-1, the highly contagious "herpes simplex virus" that causes cold sores in adults. It is sometimes known as the "kiss of death" because of the way it is passed on.

HSV-1 in babies is rare and can be prevented, but if kissed by a person who has a cold sore, a young baby can become seriously ill with the virus, as their immune system has not fully developed to fight it off.

Image copyright Ashleigh White Image caption Noah at four weeks old

Noah was just four weeks old when Ashleigh, who's from Barnsley, noticed he was starting to display the symptoms of neonatal herpes.

"His eye started to get a bit swollen and crusty, and a few days later blisters appeared, so we took him to the doctors and we were referred straight to hospital," Ashleigh told BBC Radio 5 Live Breakfast.

At first the doctors did not diagnose Noah with neonatal herpes, but Ashleigh had seen a post on Facebook from someone raising awareness of HSV-1, and persisted in telling the doctors that Noah had the virus.

"He did become very ill," she said. "I did manage to catch it in time before it did go systemic and start shutting down all his vital organs. It was around his eye and there were fears of him going blind."

Image copyright Ashleigh White Image caption Noah with the HSV-1 virus around his eye

Neonatal herpes is a rare condition, and according to the World Health Organisation, it occurs in an estimated 10 out of every 100,000 births globally, but can lead to lasting neurologic disability or death. The virus is common among adults.

Dr Liz Bragg, a paediatrician at Cardiff and Vale University Health Board, told 5 Live Breakfast: "Once you've got [the virus] you've got it forever. Between 50 and 90% of people in the world have had it and have got it living inside them. It's not infectious unless you've got an outbreak."

She also had advice for parents of newborn babies on how to avoid infection: "In the first month of life, you really do not want to be going to crowded places - you don't want to be handing the baby around because their immune system is less good at fighting off infection."

Once he was diagnosed, Noah was sent to Sheffield Children's Hospital and was given regular antiviral drugs for two weeks. He was then put on preventative antiviral drugs for another six months.

"All in all, the total time he spent in hospital was around two and half months," said Ashleigh.

Image copyright Ashleigh White Image caption Noah is out of hospital but is still has to take antiviral drugs until March next year

Ashleigh posted Noah's story on Facebook and it was shared more than 10,000 times.

"I've had a lot of messages from other parents thanking me for trying to raise awareness of how dangerous it actually is."

For more information on neonatal herpes, visit the NHS website here