Evaluation of immunization service delivery in primary healthcare centers in Akinyele and Lagelu local government areas, Oyo State, Nigeria.

Introduction: Primary healthcare is the most accessible and affordable form of healthcare for Nigerians. It offers primary prevention strategies such as routine immunization. Routine immunization at government facilities, including primary healthcares, is provided free of charge under Nigeria's Expanded Program on Immunization. However, gaps such as a shortage of healthcare workers, inadequate infrastructure, and poor supply chain management can hinder the effective delivery of immunization services. This study assessed factors affecting the quality of immunization service delivery in Primary healthcares in Akinyele and Lagelu local government areas in Oyo State, Nigeria.

Methods: A convergent parallel mixed-methods cross-sectional design was adopted, combining quantitative data from 127 healthcare workers across 40 primary healthcares from the two local government areas with qualitative data from 10 in-depth interviews. Quantitative data were analyzed using descriptive statistics and Chi-square tests, while qualitative data were analyzed thematically.

Results: Across both local government areas, over 85% of healthcare workers received pre-service or onsite cold chain training and routinely provided immunization information. In Akinyele, onsite training was significantly associated with satisfactory cold chain management (χ² = 10.039, p = 0.002), while in Lagelu, healthcare workers' knowledge was associated with satisfactory cold chain practices (χ² = 7.004, p = 0.008). Qualitative interviews revealed that Lagelu's consistent Basic Healthcare Provision Fund funding facilitated regular outreaches, whereas Akinyele's dependence on out-of-pocket payments led to intermittent services. Both local government areas faced cold chain equipment shortages and reliance on temporary staff. Quantitative and qualitative study findings show that reliable funding and targeted training ensure consistent outreach and effective cold chain management.

Conclusion: While previous studies have documented funding and cold chain gaps, this study uniquely demonstrates how localized Basic Healthcare Provision Fund access specifically stabilizes outreach but fails to address workforce and infrastructure deficits. Expansion of Basic Healthcare Provision Fund-like financing across primary healthcares, transition to permanent, competitively compensated immunization staff, investment in renewable-energy cold chain technologies, and integration of community-driven outreach into the existing healthcare framework will improve immunization service delivery.