Universal varicella vaccination programme in England
Summary of surveillance plans for the universal varicella vaccination programme in England commencing January 2026.
From January 2026 the varicella (chickenpox) vaccination programme will be implemented for eligible children in England.
This will be in the form of a combined vaccine for measles, mumps, rubella and varicella (MMRV) offered as a 2-dose schedule to children routinely at 12 months and 18 months of age. Information on eligibility criteria is available.
UKHSA’s Immunisation Divisions are responsible for monitoring and evaluating the implementation of vaccine programmes and this summarises the surveillance plans for the varicella programme.
The aims of varicella surveillance are to:
- monitor coverage of the universal varicella vaccination programme in England and identify groups with lower levels of coverage
- monitor numbers of children receiving doses administered for the catch-up programme
- monitor the impact of the vaccination programme on the epidemiology of varicella in England, in terms of burden of disease, the population groups affected and the associated health service use
- assess vaccine effectiveness of the varicella vaccination programme
- assess trends in varicella complications, severe outcomes
- monitor changes in population susceptibility to varicella over time
- asess indirect effects of varicella vaccination
- monitor inequalities in the above based on the core 20 plus approach.
- respond to MHRA requests for support with epidemiological investigation of any signals of adverse events identified by MHRA
Vaccine coverage
Vaccination will be monitored through existing systems that assess coverage including COVER and the Immunisation Information System (IIS). The latter will be able to provide regular counts of doses administered as well as proportions of those eligible under 3 years and 4 months who have received one or 2 doses of MMRV (as per relevant age cohorts).
Inequalities by sex, place and socio-economic deprivation will be regularly monitored using information from IIS on eligible children’s registered residential location (for example, postcode or alternative geography such as NHS region), with linkage to the Index of Multiple Deprivation. Monitoring inequalities by ethnicity will be dependent on recent ethnicity information being available for these cohorts.
Epidemiology of varicella cases and trends in complications and severe outcomes
The principal source of case data will be notifications of infectious disease (NOIDS) following varicella being listed as a notifiable disease in April 2025. These notifications are made on the basis of clinical suspicion by registered medical practitioners (RMPs). Inclusion of patient identifiable information (PII) facilitates the enhancement of this case information using other datasets accessed by UKHSA, while reducing the number of additional fields reported by RMPs.
Following this data linkage, this dataset will be used to describe notified cases by:
- age group
- sex
- ethnicity (to be confirmed)
- socio-economic deprivation
- hospital admissions
Although these notifications represent a proportion of cases presenting to health services, they will still be of value in identifying changing trends in the characteristics of notified cases following the introduction of the vaccination programme.
The enhanced case dataset will be used as the basis for vaccine effectiveness evaluations through linkage to vaccination records where available.
Aggregate primary care data
Pseudonymised primary care data will be used to produce aggregate counts of varicella consultations by age group, allowing this to be monitored as a time series.
Aggregate anonymised school absence data
UKHSA will pilot surveillance using aggregate counts of pseudonymised varicella-related school absences by age group monitored as a time series. This is based on information from a sentinel network of schools in England.
Population susceptibility
UKHSA will assess the effects of the universal childhood varicella programme on the long-term trends in varicella immunity among children. This will use existing serum sample collections co-ordinated by the UKHSA Sero-epidemiology unit. This will include samples originating from both primary and secondary care
Monitoring adverse events
The Medicines and Healthcare products Regulatory Agency (MHRA) is the lead agency for monitoring the safety of medicines including vaccines, using sources such as Yellow Card reports to assess whether Yellow Card reports exceed expected background rates. UKHSA can provide support for epidemiological investigations if required.