MAternal Vaccination In the NHS (MAVIS) Study: A mixed methods approach to improving antenatal immunisation rates, focusing on pertussis

Pertussis vaccination is recommended for pregnant women to give neonates passive immunity from birth when they are highly vulnerable to this prevalent infection. 30% pregnant women in the UK do not receive the vaccine.

Despite shifts to NHS maternity-service vaccine delivery to reduce barriers to uptake, coverage is declining, as it is for all child vaccinations. Maternal immunisation against multiple infant infections is developing rapidly nationally and globally. Understanding how to maximise effective delivery of such programmes is important.

This research aims to identify how NHS maternity services can be supported to improve vaccination coverage, aiming to reduce inequities between demographic groups and NHS areas, with the following research objectives (ROs): RO1: Describe common characteristics of women who did/did not receive maternal pertussis vaccination RO2: Analyse the relationship between maternal and infant vaccine uptake RO3: Explore the views of maternity service healthcare professionals (HCPs) involved in delivering the maternal pertussis programme, comparing NHS areas with high and low vaccination rates to identify intervention targets to improve uptake RO4: Explore women's views and experiences of maternal vaccination, focusing on those who missed their vaccine(s) to identify intervention targets to improve uptake RO5: Produce intervention recommendations to improve maternity-service delivery of the pertussis vaccine Methods: Project 1 (RO1, RO2): Statistical analyses of national primary care record data using logistic regression modelling to ascertain; (i)whether there are predictors of/risk factors for low uptake and (ii)associations between maternal and infant vaccination uptake (completion 01/2022).

Project 2 (RO3): (i)Development of a mixed-methods cross-sectional survey to identify barriers/facilitators to maternity-service delivery of pertussis vaccines and acceptable intervention targets, utilising theoretical frameworks of behavioural determinants, stakeholder consultation and Think-aloud user-testing; (ii)Administering national survey with HCPs at maternity services in NHS clinical commissioning group areas with the 10% highest and 10% lowest maternal pertussis vaccination coverage, with quantitative (logistic regression) and qualitative (thematic) analysis of responses; (iii)Qualitative semi-structured (thematically analysed) interviews with HCPs will supplement survey data (completion 03/2023).

Project 3 (RO4): (i)Development of a mixed-methods cross-sectional patient survey (using PPI support and methodology used in project 2) to identify barriers/facilitators to pregnant women's uptake of pertussis vaccination and acceptable intervention targets; (ii)Administering national survey to recently pregnant women via GP mailout, oversampling those who did not receive maternal pertussis vaccination (iii)Qualitative patient interviews (completion 01/2024).

Project 4 (RO5): Triangulation of findings to produce intervention recommendations to improve pertussis vaccination delivery across maternity services and to demographic groups, drawing on stakeholder and PPI consultation (completion 05/2024).

NHS Impact: This research will produce evidence-based intervention recommendations for improving maternity-service delivery of pertussis immunisation, which can immediately feed into policy and guidelines, while offering potential to inform efficient delivery of existing (influenza) and future (e.g.

RSV) maternal vaccination programmes. Dissemination: Research summaries will be shared with participating patients and HCPs.

Results will be presented to the Joint Committee on Vaccination and Immunisation, WHO Euro Technical Advisory Group of Experts (ETAGE), NHS maternity services and policymakers, published in peer-reviewed journals and conferences and disseminated via video, blogs and social media.