Researchers say vaccinating all children against chickenpox is the only way to stop deaths from the illness.
The government is considering introducing the jab
The Department of Health is awaiting a report on whether England should have a vaccine.
What is chickenpox?
Chickenpox is caused by the varicella virus and is generally a mild infection, mostly in children.
But dangerous complications can happen in a small number of children.
For every 1,000 children who catch chickenpox, on average between two and five of them will end up in hospital. And some die.
Research suggests complications do not just happen in vulnerable children with other chronic diseases and that the only way to prevent them is to vaccinate all youngsters.
Some experts say universal vaccination would therefore be the only realistic option to prevent severe complications and deaths, as few, if any, could be identified as potentially preventable under the current UK policy.
What do other experts say?
Some experts say that even if all children were not vaccinated, a smaller strategy of immunising teenagers who had not suffered the illness would prevent cases of severe disease in adults.
Experts also caution that the benefits to children from a chickenpox vaccine would have to be offset against any potential increase in adult chickenpox and shingles in the elderly.
Also, one option for universal vaccination - adding the chickenpox jab to the existing MMR vaccine - might not win public support.
Many other countries, including the US and Canada, routinely immunise their children against chickenpox.
The Department of Health has commissioned an expert sub-group to look at all the scientific and medical evidence on chickenpox vaccines and it will provide advice in due course.
What other diseases are children immunised against?
The schedule for immunisations changes from time to time in the UK. You can get an up-to-date programme from your health visitor, or go to the NHS immunisation website to find out which jabs your child will be offered, when and why.