The vaccine didn’t come in time for Laine Lewis’s son Malachi, now 12 years old. He developed a cold as a baby which deteriorated so much that he was taken to hospital, diagnosed with RSV and put on oxygen. Malachi later stopped breathing and a scan soon after revealed brain damage.

His mum has said it’s important his story “doesn’t scare people” because what happened to Malachi was very rare.

But she added: “I’d encourage people to take the vaccine for RSV because it will help their child.”

Dr Watson said the vaccine could “make a big difference to keeping babies safe” through the winter.

“I would strongly encourage any pregnant woman to discuss it with their midwife, other health professionals, and be ready to have the vaccine at their week 28 appointment, or another vaccine appointment arranged soon after that.”

Latest figures show around 64% of pregnant women in England are getting the RSV vaccine, but that falls to 53% in London.

The flu and whooping cough vaccines are also recommended during pregnancy., external

Adults aged 75 or over, or who live in a care home for older adults, are also offered the RSV vaccine across the UK.