Skip to main content

Why are children in the UK not vaccinated against chickenpox?

The chickenpox vaccine is not part of the routine UK childhood vaccination programme because chickenpox is usually a mild illness in children.

There's also a worry that introducing chickenpox vaccination for all children could increase the risk of chickenpox and shingles in adults.

Chickenpox in adults

In adults, chickenpox tends to be more severe and the risk of complications increases with age.

If a childhood chickenpox vaccination programme was introduced, people would not catch chickenpox as children because the infection would no longer spread in areas where most children had been vaccinated.

This would leave unvaccinated children susceptible to getting chickenpox as adults, when the illness is more likey to be serious, or during pregnancy, where there's a risk of the infection harming the baby.

Shingles in adults

A childhood chickenpox vaccination programme could also lead to a significant increase in cases of shingles in adults.

When people get chickenpox, the virus remains in the body. This can then reactivate later and cause shingles.

If you had chickenpox as a child, being exposed to the illness again as an adult (for example, through contact with infected children) can boost your immunity to shingles.

If children are vaccinated against chickenpox, adults will lose this natural boosting, so their immunity will drop and more cases of shingles will happen.

When is the chickenpox vaccine given?

The chickenpox vaccine is used to immunise people who may pass the infection on to someone who's at risk of serious complications from chickenpox.

The vaccine may be given on the NHS to:

  • healthcare workers who are not immune to chickenpox
  • people in close contact with someone who has a weakened immune system  

In this way, the chickenpox vaccine protects people at risk who are unable to be vaccinated against chickenpox themselves, such as:

  • pregnant women
  • people who have a weakened immune system – for example, from HIV or AIDS or through treatments such as chemotherapy

Find out more about who should have the chickenpox vaccination

Further information

Page last reviewed: 10 September 2019
Next review due: 10 September 2022