Investigating barriers to vaccine uptake in children aged 0 to 59 months within the context of the socio-political crisis in Konye Health District, South West region Cameroon

Introduction: Global immunization strategies such as the Immunization Agenda 2030 target ≥ 90% national and ≥ 80% district-level vaccine coverage, yet the Konye Health District (KHD) continues to report low uptake, with only 31.5% of children fully vaccinated amidst ongoing sociopolitical instability. This study investigated the underlying causes of poor vaccination uptake in this crisis-affected district. Method A community-based cross-sectional mixed-methods study was conducted from March to May 2023 among 412 caregivers of children aged 0–59 months. Data were collected on sociodemographic characteristics, vaccination status, perceived barriers, and existing strategies. Four health areas were selected through multistage sampling, caregivers were systematically sampled, and CHWs, facility leaders, and healthcare workers were purposively recruited for qualitative interviews. Multivariable logistic regression identified factors associated with vaccination uptake. Three focused group discussions recordings were transcribed and thematically analyzed using Braun and Clarke’s approach. Results Among 412 children, 96% had received at least one vaccine dose, but only 58% were up-to-date with their vaccination schedule. Quantitative and qualitative findings showed that vaccination completion was shaped by both caregiver and child-level factors. Children whose mothers attended antenatal care (AOR = 4.2; 95% CI: 1.2–20.7) and postnatal care (AOR = 5.0; 95% CI: 1.2–20.7) were significantly more likely to be fully vaccinated. Maternal education was a determinant, with secondary education or higher increasing vaccination completion (AOR = 3.1; 95% CI: 1.1–8.9). Male children had higher odds of full immunization compared to females (AOR = 4.35; 95% CI: 1.17–16.19). Qualitative findings reinforced these results, emphasizing the role of CHW engagement, reminders, and outreach, alongside barriers such as long distances to facilities, transportation difficulties, fear of side effects, and conflict-related disruptions. Conclusion Vaccination uptake in Konye Health District remains below global targets, largely due to barriers intensified by the sociopolitical crisis. Maternal health service use, Community health worker engagement, and access challenges are major determinants of incomplete immunization. These findings support the development of a context-specific service delivery guide to strengthen immunization in humanitarian settings.