Rate and determinants of immunisation among children under five in Ghana. A scoping review

Immunization is widely acknowledged as one of the most impactful and cost-effective public health interventions for reducing morbidity and mortality in children under five. It plays a critical role in preventing infectious diseases such as measles, pertussis, tetanus, and poliomyelitis, and is credited with saving between 4 to 5 million lives globally each year [1,2]. Despite its success, inequities in vaccine coverage persist across and within countries [3]. According to WHO/UNICEF estimates, global coverage with the third dose of the diphtheria-tetanus-pertussis (DTP3) vaccine stood at 85% in 2024, with nearly 14.3 million children classified as “zero-dose” having received no vaccines through routine services [2]. High-income countries consistently achieve over 90% coverage, while lower-middle-income and conflict-affected regions lag significantly behind [4]. While regional immunization initiatives and partnerships like Gavi, the Vaccine Alliance, have expanded access to vaccines in sub-Saharan Africa discrepancies persist wholly and geographically clustered [4,5]. For instance, a spatial analysis in Ethiopia using 2019 DHS data found persistent “zero-dose” hotspots, particularly in rural and border regions [6]. Likewise, studies from countries such as Nigeria and the Democratic Republic of Congo continue to show that children living in remote, impoverished, or conflict-affected areas are far less likely to receive complete vaccination schedules [7,8]. Though the average polio vaccination coverage in sub-Saharan Africa is approximately 85%, this still falls short of global targets, and local-level analysis often reveals much lower rates in hard-to-reach populations [9]. Across the globe, determinants of immunization status are influenced by the socio-economic, political, and healthcare contexts in which families live. In high-income countries, vaccine uptake is increasingly shaped by vaccine hesitancy, misinformation, and parental perceptions of risk and trust in healthcare systems [10,11]. Meanwhile, in low- and middle-income countries outside Africa, structural and access-related factors predominate [12]. Studies from Asia and Latin America identify low maternal education, long travel distances to health facilities, household poverty, inadequate health worker outreach, and weak health infrastructure as the most consistent barriers to childhood immunization [12–14]. In West Africa, childhood immunization is influenced by both structural barriers and social determinants such as maternal education, household income, and geographic location [15]. While the region faces challenges similar to other low- and middle-income countries, disparities in vaccine coverage often reflect uneven access to healthcare, especially between urban and rural areas [16] . In Ghana, although significant progress has been made through initiatives like the Expanded Programme on Immunization, there remain substantial gaps. Subnational disparities in coverage persist, and certain populations particularly in remote or underserved communities continue to face barriers to full immunization [17]. There have been studies that explored the determinants of childhood immunization globally and regionally but there remains a need for more context-specific syntheses. A recent systematic review examined factors influencing immunization coverage among children across Africa. The review highlighted common challenges such as maternal education, healthcare access, and socio-economic status [18] . However, the findings were aggregated across diverse settings, offering limited insight into the specific national contexts in which these challenges manifest including Ghana. In Ghana, existing research on childhood immunization is often fragmented, geographically restricted, or focused on population subgroups. As a result, there is no comprehensive synthesis that captures the full landscape of immunization coverage and its key determinants at the national level. This gap limits the ability to understand which children are most at risk of being under- or unimmunized, and why. This scoping review, therefore, aims to map the available evidence on the rate and determinants of immunization status among children under five in Ghana. Consolidating and analyzing existing studies, the review will provide a clearer picture of emerging trends, contextual drivers, and evidence gaps. The findings will inform future systematic reviews, guide policymakers and public health practitioners, and support the design of more targeted, equitable interventions. Ultimately, this work will contribute to Ghana’s progress toward universal health coverage and the reduction of child mortality which is in line with Sustainable Development Goal 3.2.