Objective To evaluate the impact of equity-focused community-engagement initiatives on the uptake of five routine childhood vaccinations.

Design Quasi-experimental study within a synthetic control analysis framework.

Setting Primary care in England between April 2019 and March 2025. Childhood vaccination data were obtained from the Cover of Vaccination Evaluated Rapidly (COVER) programme.

Intervention The Health Equity Liverpool Project (HELP) is a community-engagement vaccination initiative implemented between October 2023 and June 2024 across nine sites in central and north Liverpool. Activities were co-developed with local partners and delivered in neighbourhoods with persistently low childhood vaccine coverage. Intervention practices were defined as those located within 1 km of HELP delivery sites (n=19). A weighted combination of non-intervention practices across England (n=5826) was used to construct a synthetic control group.

Main outcomes Quarterly counts of vaccinated children following intervention implementation for first doses of the measles, mumps and rubella vaccine (MMR1 at 24 months and at 5 years), second dose of MMR (MMR2 at 5 years), pneumococcal conjugate vaccine (PCV at 24 months), the 6-in-1 vaccine, covering diphtheria, tetanus, pertussis, polio, haemophilus influenzae type b, and hepatitis B (at 12 months), and the rotavirus vaccine (at 12 months).

Results Following HELP, rotavirus vaccine uptake increased by 10.03% (95% CI 0.37% to 24.63%), corresponding to 120 (95% CI 4 to 295) additional infants vaccinated in the intervention group compared to the synthetic control. Similarly, 6-in-1 vaccine uptake rose by 11.56% (95% CI 2.37% to 25.56% ∼143 95% CI 29 to 317 additional children vaccinated. No statistically significant changes were observed for MMR1, MMR2, or PCV. Improvements were short-lived, with uptakes returning to pre-intervention levels after approximately nine months.

Conclusions Community-engagement vaccination interventions may produce a modest short-term improvement in uptake of selected early life vaccines but show limited evidence of benefit for MMR uptake. Our findings suggest that such approaches are unlikely to have a sustained impact without long-term investment, integration into existing immunisation systems and addressing the wider social determinants of health.

What is already known on this topic?

Childhood vaccination rates in England have declined over the last decade and inequalities in uptake are persistent andwidening.

Children in socioeconomically deprived areas are less likely to receive routine vaccinations, reflecting both structural barriers and vaccine hesitancy driven by misinformation and lack of trust.

Innovative community engagement interventions are recommended to address these inequalities, yet evidence of their effectiveness remains limited.

What this study adds?

Our study shows that hyperlocal community engagement interventions can increase uptake of early-life infant vaccines (rotavirus and 6-in-1) by around 10-12% but provides limited evidence of similar improvements for the MMR vaccine.

The observed improvements in infant vaccines were transient, returning to baseline levels after approximately nine months, suggesting that one-off initiatives may not produce sustained public health gains without tackling wider social determinants of health.

DHu and MAG are in receipt of grant support from Seqirus UK for the evaluation of influenza vaccines in the UK; DHu has also received grants from Merck and Co (Kenilworth, New Jersey, USA) for rotavirus strain surveillance, received honorariums for presentation at a Merck Sharp and Dohme (UK) symposium on vaccines and has consulted on rotavirus strain surveillance. Central Liverpool PCN/CT has received grant support from MSD /Merck Sharp & Dohme (UK) Limited for addressing health inequalities and improving access to childhood vaccinations. All other coauthors have no competing interests to declare.

This work was supported by the UK Arts and Humanities Research Council [Grant number: AH/Z505341/1]. XZ is also supported by ADR UK (Administrative Data Research UK), an Economic and Social Research Council (ESRC) investment (part of UK Research and Innovation) [Grant number: ES/Z502431/1].

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study used ONLY openly available human data that were originally located at the Cover of Vaccination Evaluated Rapidly (COVER) programme (https://www.gov.uk/government/collections/vaccine-uptake) and the Department of Health and Social Care Fingertips platform (https://fingertips.phe.org.uk).

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