A British mother is devastated after her newborn daughter died from the herpes virus, possibly passed on with a kiss when she had a cold sore.

Charlotte Raveney, 32, and her husband Mohamed, 28, lost their baby Mira to the herpes simplex virus-1, the same virus that causes the common cold sore, at just 10 days old.

Mira's birth last November coincided with Raveney getting her first-ever cold sore, she told Britain's Daily Mail newspaper.

Raveney had never had one and asked her midwife if it was dangerous, but was reassured it was nothing to worry about.

"The midwife said it had probably happened because I was run down after the birth and wasn't getting much sleep," she told the paper.

Four days after Raveney was discharged from the hospital, Mira became ill. They rushed her to hospital but doctors could not save her.

Five weeks later, they learned that Mira had the herpes virus and no antibodies to protect her.

“As it was my first-ever cold sore, her tiny body was unprotected,” Raveney said.

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