Chicken Pox Vaccination

This changed recently, so it is worth being precise. For years the UK did not vaccinate children against chickenpox routinely. A universal two-dose varicella programme was then introduced into the routine NHS childhood schedule on 1 January 2026, given as the combined measles, mumps, rubella and varicella (MMRV) vaccine at 12 months and 18 months. It is being rolled out in stages according to a child's date of birth, and a time-limited catch-up offer covers a defined group of pre-school children born before the programme began.

That still leaves plenty of people outside the offer. Older children, teenagers and adults are not covered by the routine schedule, and neither are children who fall between the phased rollout dates. If your child sits in one of those gaps, or you would simply rather not wait for a scheduled appointment, private chickenpox vaccination fills it. Ask us first and we will check where your child falls before you book anything, because there is no sense paying for something the NHS is about to offer.

Separately, the NHS has long vaccinated some people free of charge because of who they are around. That includes healthcare workers with patient contact who have no immunity, laboratory staff who work with the virus, and healthy people in unavoidable close contact with someone immunosuppressed, such as the sibling of a child having chemotherapy. If that describes you, start with your employer's occupational health team or your GP rather than with us.

Around nine in ten people raised in the UK are immune by the age of 15, usually because they caught chicken pox as a child without anyone writing it down. The one in ten who did not are the people we see most: adults who grew up abroad where the virus circulates differently, parents who somehow escaped it while their brothers and sisters had it, and people planning a pregnancy who want to sort it out beforehand.

It matters more in adulthood. UKHSA states plainly that the disease can be more severe in adults than in children, with pneumonia, hepatitis and encephalitis among the complications, and adults are more likely to get a day or two of fever and feeling wretched before the rash even appears. In pregnancy the risks extend to the baby as well, which is why chickenpox immunisation before conceiving is worth thinking about; the vaccine itself is never given during pregnancy.

If you genuinely cannot remember whether you had it, that is common and it is not a reason to skip vaccination. The vaccine can be given safely whether or not you have had chicken pox before, because existing immunity simply stops the vaccine virus replicating. A blood test for varicella antibodies is used in occupational health settings, and our pharmacist can talk you through whether arranging one makes sense for you. Do note that two doses give about 75% protection in adults, lower than the 98% seen in children, though breakthrough infection is much milder.

Two doses are needed. The UK Green Book sets the minimum interval at four weeks for anyone aged nine months and over, and the NHS usually describes the gap as four to eight weeks. Babies given both doses before 18 months of age need three months between them for the course to count, because residual antibody from the mother can otherwise blunt the response. We give you the date for the second dose when you have the first, and we remind you.

The appointment takes about fifteen minutes. In our private consultation room we check your history: previous chicken pox or shingles, allergies including neomycin and gelatine, whether you are pregnant or might become pregnant, any medicine that suppresses the immune system, and whether you have had blood products or immunoglobulin in the past three months. The injection goes into the upper arm, or the thigh for a small child. You leave with a written record of both doses, and we can supply a vaccination certificate if you need one for work or study.

Two vaccine products are used in the UK and one of them contains no gelatine, so tell us if that matters to you and we will use it. If you need the vaccine after being exposed to someone with chicken pox, come quickly: it works best within three days of contact, with evidence of benefit up to five days. Families come to us from Pinner, North Harrow and Ruislip as well as Harrow town centre, and we can usually fit an urgent post-exposure dose in the same day. Call us on 020 8863 6338 or book online.

The vaccine contains live but weakened virus, so some people should not have it. It is not given in pregnancy, and you should avoid becoming pregnant for one month after your last dose. It is not given to people who are severely immunosuppressed, to babies under nine months, or to anyone who has had a confirmed anaphylactic reaction to a previous dose or to a vaccine component such as neomycin or gelatine. If you are unwell with a fever on the day, we will normally rearrange.

Some things people expect to rule them out do not. Egg allergy is not a barrier, because the varicella vaccine is not egg-derived. Aspirin and other salicylates are not a reason to avoid vaccination either, although aspirin should be avoided during a natural chicken pox infection. A blood transfusion or immunoglobulin in the past three months may reduce the response, so we would usually still vaccinate and then discuss an extra dose later rather than leave you unprotected.

Side effects are usually a sore, red arm. A small number of people develop a rash within a month of vaccination. If that happens, keep the spots covered; a rash around the injection site is no reason to keep a child off nursery or school. Spread from a vaccinated person is very rare and has never been documented without a rash, but if you develop a widespread rash and live or work with someone pregnant or immunosuppressed, contact us or your GP for advice. Anything unexpected can be reported through the MHRA Yellow Card scheme.