The National Health Service (NHS) in the UK is set to implement a significant expansion of its childhood immunisation programme, announcing plans to begin vaccinating all babies against chickenpox from January next year. This marks the biggest update to the programme in a decade, aiming to transform chickenpox from a common childhood ailment into a problem of the past. Experts hail the move as a potential "life saver," with ministers highlighting its benefits in saving millions of sick days for children and preventing parents from needing to miss work or scramble for childcare.

Traditionally viewed as a mild, unavoidable "rite of passage" for children, chickenpox, caused by the highly contagious varicella-zoster virus, can lead to serious complications. While most children recover within a couple of weeks, some can develop severe issues such as pneumonia, brain inflammation (encephalitis), bacterial infections, sepsis, stroke, and, in rare cases, can be fatal. Each year in England, hundreds of babies are hospitalised due to severe symptoms, and an average of 25 people die from the illness. It also poses risks during pregnancy, affecting both mother and baby. The virus is exceptionally contagious, with each infected person typically transmitting it to 10 others, making it far more transmissible than the common cold or flu.

The new chickenpox vaccine, also known as the varicella vaccine, will be integrated into a new combined Measles, Mumps, Rubella, and Varicella (MMRV) jab, replacing the existing MMR vaccine. This live vaccine contains a weakened version of the chickenpox virus and will be administered in two doses to over half a million children annually, specifically at 12 months and 18 months of age. The introduction of this routine vaccination aligns the UK with numerous other countries, including Germany, Canada, Australia, and the US, which have long incorporated varicella vaccination into their public health strategies.

Regarding effectiveness, NHS data indicates that approximately nine out of ten children develop immunity after a single chickenpox jab, with this figure increasing further after both doses. However, immunity may wane over time, with about three-quarters of vaccinated teenagers and adults retaining protection. While natural infection typically provides almost universal and lasting immunity, the vaccine is confirmed to significantly reduce the risk of developing chickenpox or experiencing a severe case. The jab is considered safe by experts, with common, mild, and short-lasting side effects such as a sore arm, mild rash, and high temperature. Serious allergic reactions are exceedingly rare, occurring in about one in a million cases. Millions of doses have been safely administered globally since 1995, without evidence of increased health risks. The MMRV jab by Merck & Co. does carry a small seizure risk, estimated at one additional seizure per 2,300 doses, but the Joint Committee on Vaccination and Immunisation (JCVI) has deemed this "very small increased risk" not clinically concerning.

The decision to roll out the vaccine follows a re-evaluation of previous concerns. Historically, there was a theory that widespread childhood vaccination against chickenpox might lead to a problematic increase in shingles, a condition also caused by the varicella-zoster virus, or result in more severe chickenpox cases in adults who had not been exposed as children. However, updated evidence has repeatedly disproved this theory. In November 2023, the JCVI officially recommended the jab for children, concluding that the vaccine's benefits substantially outweigh any potential risks.

The benefits of this programme are multi-faceted. Health Minister Stephen Kinnock emphasized the peace of mind it offers parents and the economic advantages, with an estimated £24 million in lost income and productivity saved annually due to fewer parents missing work. The NHS also anticipates saving £15 million each year in treatment costs for chickenpox. More importantly, it safeguards children from severe forms of the illness and its potentially life-threatening complications, fostering a healthier generation.

Currently, chickenpox vaccines are available free on the NHS only to specific high-risk individuals, such as those in close contact with immunocompromised people. Privately, the jab costs around £150. The new programme targets all babies, and health officials are also exploring a catch-up programme for millions of under-fives, though the vaccine is not expected to be made available to older children through the NHS.

Despite this groundbreaking expansion, the NHS faces ongoing challenges with childhood vaccine uptake. Data reveals a concerning decline in MMR vaccine rates, reaching the lowest levels in 15 years, with less than 92% of five-year-olds having received one dose and uptake for two-year-olds at about 89% in 2024/25. None of England's routine childhood vaccines met the 95% uptake target in the last fiscal year, underscoring the battle ahead for health authorities to encourage broader participation in immunisation programmes.

Alongside the chickenpox vaccine, other adjustments to the childhood immunisation schedule will take effect. From January 2026, the second dose of the MMR vaccine will be moved from three years and four months to 18 months. Changes in July will see the Pneumococcal vaccine (first dose) moved from 12 weeks to 16 weeks, and the third dose of the 6-in-1 vaccine moved from 16 weeks to 12 weeks. The Hib/MenC vaccine (first dose) and the third dose of the MenB vaccine, both previously given at one year, will be removed from July. An additional fourth dose of DTaP/IPV/Hib/HepB will be introduced at 18 months from January 2026.

Chickenpox typically presents with an itchy, spotty rash that can appear anywhere on the body, often accompanied by a high temperature, aches, and loss of appetite. Individuals infected are advised to remain off school, nursery, or work until all spots have scabbed over, usually about five days after the rash first appears, to prevent further spread.