Peer-reviewed article
Respiratory syncytial virus epidemiology and effectiveness of infant nirsevimab: 2024 results from the Australian Sentinel Hospital Network (FluCAN-PAEDS).
Blyth CC, Wadia U, Britton PN, Carr J, Clark JE et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study reports on respiratory syncytial virus (RSV) hospitalisations in Australia during 2024 and evaluates the effectiveness of nirsevimab, a new monoclonal antibody used to prevent RSV in infants. The research found that infants under 6 months, First Nations children, and those born prematurely or with underlying medical conditions faced the greatest risk of severe RSV disease. Nirsevimab showed 83% effectiveness in preventing hospitalisation in infants under 12 months in two Australian jurisdictions that implemented population-wide immunisation programmes.
Key points
- Infants under 12 months accounted for 38.4% of 3,998 hospitalised RSV cases
- Children under 6 months, First Nations children, preterm infants, and those with underlying medical conditions were at greatest risk of severe outcomes
- Nirsevimab demonstrated 83.1% effectiveness against hospitalisation in infants under 12 months (95% CI: 67.4-91.3)
- RSV vaccine uptake in pregnancy and adults over 60 years was limited in 2024, preventing effectiveness assessment
- National sentinel surveillance system established across 22 hospital sites enabled rapid data collection and evaluation of immunisation products
Limitations
The study could not assess the effectiveness of RSV pregnancy vaccines or adult vaccines due to limited uptake in 2024. Effectiveness findings are specific to two Australian jurisdictions with population-wide nirsevimab programmes and may not represent effectiveness across all Australian contexts.
Abstract
BACKGROUNDRespiratory syncytial virus (RSV) is a leading cause of morbidity and mortality in young children and older adults. A long-acting anti-RSV monoclonal antibody (nirsevimab) and bivalent pre-fusion F-protein pregnancy vaccine became available to prevent RSV in young children in 2024; two RSV vaccines for adults ≥ 60 years were also available.AIMTo report 2024 RSV epidemiology in Australia, identify risk factors for severe outcomes, and use and effectiveness of RSV immunisation products.METHODSNational sentinel hospital-based RSV surveillance was established in 2024, recruiting hospitalised laboratory-confirmed RSV cases and test-negative controls from 22 sites in a national hospital network (FluCAN-PAEDS).RESULTSBetween April and December 2024, 3,998 subjects (3,415 children; 582 adults) were hospitalised with RSV. Most cases were infants < 12 months (n = 1,534; 38.4%); 1,661 (41.5%) had underlying medical conditions. Children < 6 months, First Nations children, those born preterm or with underlying medical conditions (cardiac, neurological, genetic and metabolic disease/disorders, immunosuppression) were at greatest risk of severe outcomes. Severe outcomes were more frequent in adults with malignancy, respiratory or cardiac disease. Nirsevimab effectiveness against hospitalisation in infants < 12 months in the two Australian jurisdictions with population-wide immunisation programmes was 83.1% (95% CI: 67.4-91.3). RSV vaccine use (pregnancy; adults ≥ 60 years) was limited, precluding effectiveness assessments.CONCLUSIONNational surveillance enabled timely 2024 data collection with the capability to evaluate effectiveness of immunisation products preventing RSV. Nirsevimab demonstrated comparable effectiveness to that in the northern hemisphere, informing Australia's 2025 strategy. Evaluation to assess the impact of more widespread uptake of RSV prevention products continues.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Nirsevimab, a long-acting anti-RSV monoclonal antibody administered to infants
- Population
- Infants under 12 months hospitalised with laboratory-confirmed RSV in two Australian jurisdictions with population-wide immunisation programmes
Key finding
Nirsevimab effectiveness against hospitalisation in infants under 12 months was 83.1% (95% CI: 67.4-91.3)