Role of Information Sources in Vaccination Uptake: Insights From a Cross-Sectional Household Survey in Sierra Leone, 2019

INTRODUCTION: There is limited understanding of the potential impact of information sources on vaccination attitudes and behaviors in low-income countries. We examined how exposure to immunization information sources may be associated with vaccination uptake in Sierra Leone. METHODS: In 2019, a household survey was conducted using multistage cluster sampling to randomly select 621 caregivers of children aged 12–23 months in 4 districts in Sierra Leone. We measured exposure to various sources of immunization information and 2 outcomes: (1) vaccination confidence using an aggregate score (from 12 Likert items, informed by previously validated scale) that was dichotomized into a binary variable; (2) uptake of the third dose of diphtheria-pertussis-tetanus-hepatitis B-Haemophilus influenzae type-b-pentavalent vaccine (penta-3) based on card record or through caregiver recall when card was unavailable. Associations between information sources and the outcomes were examined using modified Poisson regression with robust variance estimator. RESULTS: Weighted estimate for penta-3 uptake was 81% (75.2%–85.5%). The likelihood of uptake of penta-3 was significantly greater when caregiver received information from health facilities (adjusted prevalence ratio [aPR]=1.26, 95% confidence interval [CI]=1.1, 1.5), faith leaders (aPR=1.16, 95% CI=1.1, 1.3), and community health workers (aPR=1.13, 95% CI=1.003, 1.3). Exposure to greater number of information sources was associated with high penta-3 uptake (aPR=1.05, 95% CI=1.02, 1.1). DISCUSSION: Immunization information received during health facility visits and through engagement with religious leaders may enhance vaccination uptake. Assessments to understand context-specific information dynamics should be prioritized in optimizing immunization outcomes.