Study published on impact of Ireland’s national nirsevimab immunization programme on RSV morbidity amongst infants

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The latest study on the impact of Ireland’s national nirsevimab immunization programme on RSV morbidity amongst infants during the 2024-25 season has been published in Vaccine.

The research details the programme’s effect on RSV morbidity among infants during the 2024-25 season.

During the 2024/2025 winter season in eligible infants Ireland saw:

  • 83% immunisation coverage
  • 68% reduction in laboratory-confirmed RSV cases compared with the previous season
  • An estimated 1055 RSV notified cases, 459 ED presentations, 437 hospitalisations, and 76 ICU admissions were averted in the 2024/2025 birth cohort.
  • Disease prevented fraction was 74.5%, meaning that nearly 75% of disease was prevented due to this programme, leading to reduced pressures in paediatric hospitals last winter.

Read the article via ScienceDirect here: Protecting infants from respiratory syncytial virus (RSV) in Ireland: Impact of a national nirsevimab immunisation programme, 2024/2025 - ScienceDirect

Huge thanks to the frontline clinicians who made this programme a success—our midwives across 19 maternity units, community vaccinators and the teams at CHI and TCP.

We are grateful also to our Steering and Implementation teams for leading its rollout. Dr Éamonn O’Moore and Ciaran Browne co-chaired the RSV Steering Group. An Implementation Working group, chaired by Dr Augustine Pereira, Public Health lead for the RSV pathfinder programme, drafted the blueprint for the delivery of the programme which received government approval. The National Immunisation Office and Regional Departments of Public Health provided clinical and Public Health leadership to the programme. Angela Dunne, National Lead Midwife and Dr John Murphy played a key role in the design phase of the programme and led the engagement with maternity units across the country. Dr Michael Hanrahan led the overall evaluation of the pathfinder programme and impact analysis was conducted by Laura Paris, former HPSC EPIET Fellow and lead author on the Vaccine article.

The evaluation of the newborn programme in 2024-25 facilitated an expansion in 2025-26 to a catch up cohort of infants born between March and September and we also wish to thank the community vaccinators and regional teams including the regional Public Health departments who spearheaded the expanded programme this year.

HPSC and NIO also provided Public Health leadership throughout the pathfinder programmes.

We wish to also acknowledge the Department of Health & CMO’s office for their approval of the programme. Thanks also to our CCO and CEO of the HSE for their support of the pathfinder programme, which has given us vital real-world evidence that will inform future immunisation policy.

The full evaluation report can be found on the HPSC website