Social Signaling for Childhood Immunization in Sierra Leone: Malaria Vaccine Integration and Building a Pathway to Scale

This study supports the Government of Sierra Leone in accelerating uptake and reducing drop-off of routine childhood immunizations, including the newly introduced 4-dose malaria vaccine. Building on rigorous evidence from a 2016–2018 randomized controlled trial (RCT) showing that colorful bracelets given to caregivers of timely vaccinated infants increased immunization completion by up to 13 percentage points, we adapt and scale this low-cost social incentive intervention in the current immunization context. Our ongoing 3-arm RCT, conducted in partnership with the Ministry of Health (MoH) and Innovations for Poverty Action (IPA), tests two bracelet implementation models across 255 clinics to improve timely malaria vaccine initiation and completion alongside routine vaccines. Parallel MoH-led implementation is underway in 75 additional clinics, providing a platform for scale.With IGI support, we will conduct a process evaluation assessing implementation fidelity under MoH management, the effectiveness of cascade training, and key factors driving immunization uptake. Data collection and monitoring will inform integration of bracelets into MoH’s routine systems and vaccine supply chain. Findings will support the development of a national scale-up toolkit and roadmap, fostering institutionalization of the intervention to sustainably improve immunization outcomes across Sierra Leone.