Association of access and acceptance barriers with under- and non-vaccination of children <5 years in Australia: A national cross-sectional survey of parents

OBJECTIVES: Data on barriers to childhood vaccine uptake are needed to understand and address declining coverage. This study aimed to measure access and acceptance barriers to routine childhood vaccination faced by parents in Australia. STUDY DESIGN: National cross-sectional online survey. METHODS: We recruited Australian parents/carers of children aged <5 years using an online panel from March-April 2024. We measured 15 access and acceptance barriers to routine childhood vaccine uptake using the validated Vaccine Barriers Assessment Tool. Parents reported their child's vaccination status (up-to-date, partially vaccinated, or unvaccinated) and demographics. We calculated prevalence of vaccination barriers and associations between barriers and parent location, financial stress, number of children, and child vaccination status. Data were weighted using the 2021 estimated resident parent population. RESULTS: Of 2000 parents surveyed, 94.0 % reported up-to-date child vaccination, 4.5 % partial, and 1.5 % unvaccinated. In all three vaccination status groups the most common barrier was feeling distressed when thinking about vaccination (60.2 % in total). Compared to parents of up-to-date children, the partially vaccinated group reported more access barriers like difficulty getting an appointment (24.8 % vs 8.5 %, PD 16.3 %, 95 % CI: 6.3-26.3) and affordability (20.5 % vs 10.4 %, PD 10.0 %, 95 % CI: 0.7-19.3). Acceptance barriers like not believing vaccines are safe were more associated with non-vaccination. CONCLUSIONS: Along with strategies to improve vaccine acceptance, interventions addressing access issues like reducing appointment costs should be prioritised for partially vaccinated children. Annual assessment of social and behavioural barriers amenable to intervention will enable comparison over time to inform policy and practice.