Michelle A. SagalaMichael SitawaJoyce Jebet2026-06-162026-06-162025-082663-4996https://repository.ndu.ac.ke/handle/123456789/186Vaccination is vital to public health security, especially in refugee settings where health systems are often weak. This study examined health system barriers influencing vaccination uptake among caregivers of children aged 0–14 years in the Dadaab refugee complex, Kenya. A mixed-methods design was used, combining data from 380 survey respondents and qualitative inputs from key informant interviews and a focus group discussion. Findings revealed wide disparities in vaccine coverage across camps, Dagahaley (99.1%), Hagadera (65.0%), and Ifo (22.0%), attributed to inconsistent healthcare delivery, workforce shortages, and access barriers. Multivariate analysis showed that camp location and incomplete immunization histories significantly predicted low uptake. Qualitative data highlighted additional barriers, including language gaps, poor coordination, and mistrust. Despite vaccine availability, systemic inequities persist. Strengthening routine services, improving access, and fostering community engagement are essential for improving vaccine uptake and enhancing health security in refugee settings.enArticle