Childhood vaccination uptake and associated determinants among caregivers of young children in Cape Town, South Africa

BACKGROUND: Despite high overall vaccination coverage in South Africa, maintaining optimal coverage is persistently challenged by complex factors, including vaccine hesitancy and access barriers. The World Health Organization's Behavioural and Social Drivers (BeSD) framework provides a comprehensive framework for systematically analysing the determinants of vaccine uptake. This study aimed to estimate the rate of uptake of vaccines and identify associated factors among a sample of caregivers of children aged 0-2 years in the Cape Town Metropolitan Health District. METHODS: A cross-sectional survey was conducted in high, mixed, and low-density subdistricts of Cape Town between August 2024 and February 2025, recruiting 250 caregivers of children aged 0-2 years. Demographic and behavioural determinants of vaccination uptake were analysed using binomial regression, informed by the BeSD framework. RESULTS: Overall uptake was high, with 93% (95% CI: 89% to 95%) of children fully vaccinated for their age, and 99% having received at least one dose of any vaccine. Caregiver motivation was robust, as 97% expressed being "very willing" to ensure their child receives all recommended vaccines. However, significant demographic associations and barriers persisted. Full vaccination was significantly associated with married caregiver status (RR = 1.07, p = 0.015) and residence in the low-density Tygerberg subdistrict compared to Mitchells Plain (RR = 1.09, p = 0.049). Conversely, the likelihood of full vaccination decreased significantly with increasing child age (RR = 0.99, p = 0.039) and higher birth order (RR = 0.97, p = 0.007). Practical constraints were notable, with 81% of caregivers reporting unemployment. Furthermore, 63% reported long queues, and 26% reported unsatisfactory service quality. Socially, decision-making was primarily driven by mothers (77%), and only 22% of caregivers reported recently hearing about vaccines, suggesting gaps in external communication. CONCLUSION: Caregivers recruited in the study demonstrate high motivation and vaccine confidence. However, structural vulnerabilities related to single parenting, larger family sizes, and geographic location persist as barriers to full vaccination. The decline in uptake as children grow older highlights a particular need to strengthen retention strategies for the 18-month visit. Findings indicate the need for interventions targeting structural barriers that influence childhood vaccination rates.