Published in PLOS One on 2026-06-05, this study is presented as an attributed evidence briefing. The excerpts below are the original researchers’ words, reproduced under their Creative Commons Attribution licence. Health Signal has selected the abstract and, where needed, opening background paragraphs; the complete methods, results, limitations and references remain in the linked paper.
Original authors: Florence Gyembuzie Wongnaah, Augustus Osborne, Khadijat Adeleye, Bright Opoku Ahinkorah, Bereket Yakob
Source: PLOS One • DOI 10.1371/journal.pone.0349584
Read the complete primary study ↗ · Creative Commons Attribution licence
From the researchers
Abstract
Immunization remains a cornerstone of child survival and population health. While Ghana has made significant strides in vaccine delivery over the past three decades, gaps in equitable and universal coverage persist. This study examined the progress and gaps in full immunization coverage among two-year-olds in Ghana from 1993 to 2022.
We used data from the Ghana Demographic Health Survey rounds conducted between 1993 and 2022 to examine full immunization coverage among two-year-olds. Disaggregated data were accessed via the WHO Health Equity Assessment Toolkit (HEAT). Inequality was assessed across six dimensions: maternal age, household wealth status, maternal education, place of residence, child’s sex, and subnational region. Various inequality measures, including difference, ratio, population-attributable risk, and population-attributable fraction were calculated.
Full immunization coverage improved from 55.5% in 1993 to 71.5% in 2022, peaking at 77.6% in 2008. Inequality analysis showed reduced socioeconomic disparities related to wealth, maternal education, and urban-rural residence by 2022. However, two key inequalities persisted: maternal age-related inequality significantly widened to 26.8 percentage-point gap in 2022 between mothers aged 20–49 and adolescent mothers (15–19 years), and substantial regional disparities remained, with a significant 39.8 percentage-point gap between the best- and worst-performing regions.
Despite the gains in full immunization coverage in Ghana over the past three decades, significant inequalities persist, particularly among adolescent mothers and populations in disadvantaged regions. Strengthening equity-focused immunization strategies is essential to achieving universal coverage.
Introduction
Immunization is a fundamental pillar of public health intervention, serving as a critical defence mechanism against preventable infectious diseases, particularly for vulnerable young children [1,2]. This significance is magnified by global demographics, with UNICEF reporting approximately 680 million children under five years worldwide, including 4 million in Ghana [3]. The period from birth to two years represents a crucial developmental window [4], during which children are especially susceptible to infectious diseases due to their developing immune systems [5,6]. This vulnerability, coupled with the proven effectiveness of early vaccination, underscores the urgent need for comprehensive immunization coverage during these formative years.
The World Health Organization and national health authorities have established robust vaccination protocols as one of the most cost-effective strategies for reducing childhood morbidity and mortality [7–9]. Ghana’s implementation of the Expanded Program on Immunization (EPI) in 1978 marked a significant milestone in the nation’s public health history, facilitating systematic vaccine delivery and substantially reducing preventable childhood diseases [10]. This program’s implementation has been particularly crucial in addressing developing nations’ complex health challenges, where infectious diseases pose significant threats to child survival and development.
The emphasis on immunization for children under two years is grounded in multiple scientific and public health rationales. Critical among these is the establishment of early immunity, which protects individual children and contributes to community-wide disease resistance through herd immunity [11]. Furthermore, early childhood vaccination aligns strategically with global health initiatives, particularly the Sustainable Development Goals (SDGs), specifically SDG 3, which focuses on ensuring healthy lives and promoting well-being for all ages [12,13]. Immunization directly contributes to several targets of SDG 3, including reducing child mortality, preventing the spread of infectious diseases, and ensuring universal health coverage [12]. By preventing diseases such as measles, polio, and hepatitis, immunization not only safeguards the health of children but also fosters healthier communities, thereby playing an integral role in achieving broader global health objectives and sustainable development targets [13]. While Ghana’s EPI program has achieved remarkable progress, with national immunization coverage rates reaching 90–95% for most vaccines over the past decade, significant challenges persist [14]. These challenges are particularly evident in the disparities between urban and rural areas and among different socioeconomic groups. The complexity of achieving and maintaining high immunization coverage is further complicated by geographical accessibility issues, healthcare resource distribution inequities, and varying levels of health literacy among different population segments [15,16]. These factors contribute to creating pockets of under-immunized children, particularly in rural areas and urban slums, where healthcare access remains limited.
Reading this evidence
Use the full paper to check the study design, participant selection, comparator and outcome definitions before drawing a practical conclusion. An association does not by itself show cause and effect. A reported performance measure needs its denominator and uncertainty. A finding from a particular facility, sample or time period should retain that scope when it is discussed elsewhere.
This briefing makes the source accessible within the wider public health desk. It does not assess an individual patient or certify a product. When considering relevance to another health system, examine the original authors’ account of context and limitations, then seek local implementation evidence. The related reporting below provides other studies to read alongside this one; it is a topic connection, rather than a claim that their results are directly comparable.
© 2026 Florence Gyembuzie Wongnaah, Augustus Osborne, Khadijat Adeleye, Bright Opoku Ahinkorah, Bereket Yakob. Excerpts reproduced under CC BY. Selection, formatting and contextual notes by Health Signal. The researchers are the authors of the source study, not members of Health Signal’s staff.
Explore connected evidence
- Evidence brief: Sociodemographic and geographic determinants of childhood immunization coverage and equity in Ghana: Analysis of the 2022 demographic and health survey
- Evidence brief: Magnitude of childhood immunization and its associated factors in Sub-Saharan Africa: A mixed effect count regression analysis
- Evidence brief: Challenges, opportunities and best practices in routine childhood vaccination services delivery in urban slums and pastoralist regions of Ethiopia: An exploratory qualitative study in marginalized settings
