Chickenpox vaccine: All young children in England and Wales to be offered free vaccine by NHS from January next year

It will be given as two doses, at 12 and 18 months of age, combined with the existing MMR jab which protects against measles, mumps and rubella. A catch up campaign is planned for slightly older children so they don't miss out.

Until now, parents who wanted to protect their child against the chickenpox varicella virus, which causes red itchy spots, have usually had to pay up to £200 privately. Ministers hope offering the vaccine free will not only protect youngsters from the severe, although rare, complications of chickenpox, but also save parents taking time off work to look after a sick child.

According to the Department of Health and Social Care, chickenpox causes an estimated £24m in lost income and productivity every year in the UK. Health minister Stephen Kinnock said: "We're giving parents the power to protect their children.

"This vaccine puts children's health first and gives working families the support they deserve." Chickenpox is generally mild but can be very severe for some people. Pregnant women are particularly at risk as it can cause complications for both the mother and her baby.

Very young infants and adults are also more likely to experience serious illness compared to children. In rare cases it can cause a swelling of the brain, called encephalitis, an inflammation of the lungs, called pneumonitis, and stroke, which can result in hospitalisation and, in very rare cases, death.

Experts say vaccination will dramatically reduce the number of chickenpox cases overall, leading to far fewer of the more serious ones.