Should your child have the chickenpox vaccine?

There's a worry that vaccinating children against chickenpox could increase the likelihood of grown-ups getting chickenpox and shingles (a related illness). And for adults, chickenpox (and shingles) can be much more serious than it is for most children – and the risk of complications increases as you get older.
Dr Philippa Kaye, expert family GP

So I can't get my child the chickenpox vaccine on the NHS?

No, not unless your child is in close contact with someone who has a weakened immune system or who is at risk of serious illness if they catch chickenpox. If you think this applies to your child, you should contact your GP.

Can I pay for my child to have the chickenpox vaccine? How much does it cost?

Yes, as long as your child is over 12 months old, you can pay to have them given the chickenpox (varicella) jab privately – at a travel clinic or at selected high-street pharmacies, such as Boots. The cost varies but is currently between £65 and £100, and there are usually 2 doses needed, given 4 weeks apart.

But children get vaccinated against chickenpox in other countries. Why is it different in the UK?

It's true that several countries vaccinate children against chickenpox, including the US, Australia and Germany. Most do this by adding the varicella vaccine to the MMR jab, turning it into an MMRV jab.

The Joint Committee on Vaccination and Immunisation (JCVI), the body that advises the UK government on immunisation, currently says it would not be cost-effective to introduce the chickenpox vaccine into the routine UK childhood vaccination schedule, either as a single vaccine or in an MMRV jab.

This cost-effectiveness calculation will have included the estimated cost to the NHS of the forecast rise in cases of shingles.

Can't chickenpox be serious for some children?

Yes, it can. For most, it's a mild illness, as Dr Philippa says but, for a very small number of children (under 1 in 100, 000, according to a 13-month surveillance study of children in the UK and Ireland²), chickenpox can lead to severe complications. "Complications of chickenpox," says Dr Philippa, "include secondary bacterial skin infections or, more rarely, lung infection and inflammation [pnuemonia] and brain inflammation [encephalitis]."

The children most at risk of chickenpox complications are those with compromised immune systems (perhaps because they are being treated for cancer) and very newborn babies (if their mother catches chickenpox close to the birth).

More like this

NHS statistics for 2108-9³ show that, in that year, 4,094 children under 14 with a diagnosis of varicella (chickenpox) were taken to hospital, with 143 of those treated for meningitis, encephalitis or pneumonia. Childhood deaths from chickenpox range between 4 and 9 a year.²

So why would you not vaccinate your child, if you can afford it?

It's a difficult one, this – because we're balancing one part of the population (children) against another (adults).

Varicella (the virus that causes chickenpox) generally causes only mild illness if caught as a child – but not always (as we've seen). It's much more likely to cause serious illness and complications if caught (or reactivated as shingles) as an adult. So, while vaccinating children can protect them from the (very small) risk of serious illness (or death), the worry is that, if every child is vaccinated, it could mean more adults get both chickenpox and shingles and that they wouldn't recover nearly as well.

To complicate matters further, it has to be said that some experts are now beginning to think that the worry about shingles may have been overstated.^4,5 "I think it is reasonable to say that the shingles risk may have been overestimated in the UK," says Dr Philippa, "and it is being looked at again by the JCVI."

Until the JCVI says different, though – if indeed it does – Dr Philippa advises following the NHS recommendation that immunisation is not required. But she recognises that, as the vaccine is available privately, it is up to parents to decide.

"As chickenpox tends to be more severe in adults," she adds, "perhaps one option is to wait and only pay for the vaccine if your child reaches puberty without yet having had chickenpox."

What's the connection with shingles? And why does it matter?

Shingles is a disease that only people who've previously had chickenpox can get. It's caused by the same virus – varicella – that causes chickenpox. And, once you've had chickenpox, the virus can lie dormant and then reactivate as shingles later in life.

Shingles lasts longer than chickenpox (4 weeks on average), is very painful and can lead to much more severe complications, especially if you get it in old age.

Experts think that being around children who've got chickenpox can boost your immunity to varicella in a way that makes it less likely that you'll get shingles.⁶ In other words, allowing our children and grandchildren to get chickenpox can protect us from getting shingles (assuming we've already had chickenpox ourselves).

But if all children are given the chickenpox vaccine, there wouldn't be that pool of chickenpox-y children to boost adult immunity – and that could mean a big increase in the number of adults who get shingles.

Initial studies of the US chickenpox vaccination programme⁷ seemed to bear this out but, recently, the JCVI has started to review the data from other countries^4,5 to see what impact routine chickenpox vaccination is having in those countries on cases on both chickenpox and shingles. The JCVI will then advise the government on whether the vaccine should be introduced here, too.

About our expert GP Philippa Kaye

Dr Philippa Kaye works as a GP in both NHS and private practice. She attended Downing College, Cambridge, then took medical studies at Guy’s, King’s and St Thomas’s medical schools in London, training in paediatrics, gynaecology, care of the elderly, acute medicine, psychiatry and general practice. Dr Philippa has also written a number of books, including ones on child health, diabetes in childhood and adolescence. She is a mum of 3.

Pics: Getty

References

^{1. Chickenpox: an overview. NHS online
2. Severe complications of chickenpox in hospitalised children in the UK and Ireland. Cameron, JC et al. Arch Dis Child. 2007;92 (12):1062–1066. doi:10.1136/adc.2007.123232
3. Hospital admitted patient care activity 2018-19: Diagnosis. 19 Sep 2019. NHS Digital
4. Chickenpox (Varicella) vaccine. Vaccine Knowledge Project}^{5. Why isn't the chickenpox vaccine available on the NHS? Harvey, G. Patient.info
6. Chickenpox, chickenpox vaccination, and shingles, PD Weslby. Postgrad Med J. 2006;82(967):351–352. DOI:10.1136/pgmj.2005.038984}^4.^{7. Review of the United States universal varicella vaccination program: herpes zoster incidence rates, cost-effectiveness and vaccine efficacy base primarily on the Antelope Valley Varicella Active Surveillance Project data. Goldman, GS. Vaccine. 2013 Mar 25;31 (13): 1680-94. doi: 10.1016/j.vaccine.2012.05.050. Epub 2012 Jun 1.}