Timing is everything: optimizing maternal RSV immunization through ANC attendance patterns and timing in Viet Nam

This study demonstrates the importance of aligning maternal RSV immunization strategies with ANC attendance patterns across levels of care in Viet Nam. Primary facilities, characterized by earlier and more frequent ANC engagement, are critical platforms for maternal vaccination. Adopting the wider WHO-recommended eligibility window, strengthening early ANC counseling, expanding public-sector access, and improving digital continuity of care are essential to achieving equitable national rollout.