Respiratory syncytial virus (RSV) is a common respiratory virus that can infect people of all ages and usually causes mild, cold-like symptoms. Most people recover in a week or two, but RSV can be serious and lead to severe conditions such as bronchiolitis in infants and pneumonia. Infants and older adults are more likely to develop severe RSV and need hospitalisation. RSV is spread through droplets from an infected person’s cough or sneeze.
RSV is recognised as one of the most common causes of childhood illness and is the most common cause of hospitalisation in infants. Early-life RSV infection has been associated with significant long-term respiratory issues, including recurrent lower respiratory tract infections, recurrent wheezing, asthma, and lung function impairment, and these conditions can persist into adulthood as chronic respiratory disease.
Almost all children experience at least one RSV infection within their first two years of life.
In NSW between 2016 and 2023, there were more than 45,000 hospitalisations with an RSV diagnosis, of which approximately 47% were in children aged less than 1 year.
For more information refer to the NSW RSV Prevention Program – Clinicians Guide.
In NSW, RSV hospitalisations are more common in autumn and winter (March to August) – however, they occur year-round.
In 2025 all infants will be offered protection from severe RSV disease:
RSV vaccines are not currently available for infants in Australia or internationally.
Both Abrysvo® and nirsevimab are designed to protect infants against severe RSV disease through passive immunisation.
When a pregnant woman receives Abrysvo®, her immune system produces antibodies to RSV in the first few weeks after the vaccination. The placenta transports these antibodies to the foetus. The antibodies protect the infant from severe RSV disease after birth for up to 6 months.
Nirsevimab is a monoclonal antibody for use in infants and young children to protect against severe respiratory syncytial virus (RSV) infection. Nirsevimab is a passive immunisation that provides antibodies directly to the infant so they have immediate protection against RSV that lasts for their first 6 months of life.
A single dose of Abrysvo® is funded under the NIP for all pregnant women and recommended at 28 to 36 weeks gestation. Abrysvo® should be offered to pregnant women at the 28-week antenatal appointment to ensure a high level of antibodies is transferred to the baby and maximise protection for infants who are born prematurely.
Please note that Abrysvo® is registered for use from 24 weeks to 36 weeks however is not recommended for use from 24 to ≤28 weeks until additional safety and efficacy data is available.
Abrysvo® can be given beyond 36 weeks gestation however infants may not be adequately protected if they are born within 2 weeks of the mother receiving the vaccine. If delivery occurs within 2 weeks of the mother receiving Abrysvo®, the infant is recommended to also receive nirsevimab (see below eligibility for funded nirsevimab in NSW).
Under the current NSW Health RSV Vulnerable Babies program all babies most vulnerable to severe illness from RSV are eligible for nirsevimab. This program commenced on 25 March 2024 and will end on 16 March 2025 and is only available through treating hospitals. Refer to the NSW RSV Prevention Program – Clinicians Guide – eligibility information.
From 17 March 2025, under the new NSW RSV Prevention Program, nirsevimab is recommended and funded by NSW Health for all infants at birth who are not protected by maternal RSV vaccination and for infants who have risk conditions for severe RSV disease. Children up to 24 months of age with risk conditions for severe RSV disease and children requiring catch up will also be eligible to receive nirsevimab. Refer to NSW Health RSV Prevention Program: Eligibility for detailed information.
Advice about repeat vaccination of Abrysvo® in subsequent pregnancies is not available yet and will be provided when more data becomes available.
Eligible infants and children can access nirsevimab from a range of healthcare providers.
All eligible newborn infants should be offered nirsevimab before they are discharged from hospital. However, if a newborn infant is not immunised with nirsevimab before they are discharged from hospital, they can receive nirsevimab up to 6 months of age from their GP, community health centre or Aboriginal medical service.
Primary care providers such as GPs, Aboriginal medical services and community health centres can order nirsevimab for eligible infants up to 24 months of age who remain vulnerable to severe RSV disease and infants requiring catch up using the Nirsevimab Order Form on the NSW Vaccine Centre.
One form for each individual child must be completed. The Nirsevimab Order Form can be found by logging into the NSW Vaccine Centre and will be available from 10 March 2025.
No. A repeat dose of nirsevimab is not recommended for infants that received nirsevimab outside of the peak RSV activity period under the 2024 NSW RSV Vulnerable Babies Program who are entering their first RSV season in 2025. RSV circulates year-round and babies are most at risk in the first few months of life.
However, children up to 24 months of age with risk conditions for severe RSV entering their second RSV season are recommended to receive nirsevimab prior to the peak RSV season (from March onwards), regardless of whether they previously received a dose of nirsevimab. Refer to NSW Health RSV Prevention Program: Eligibility for more information.
In clinical trials, Abrysvo® was found to reduce the risk of infant hospitalisation from RSV disease by 57% for up to 6 months. In addition, Abrysvo® efficacy was 70% in protecting infants from severe medically attended RSV-confirmed lower respiratory tract infection (LRTI) in their first 6 months of life.
Each dose of nirsevimab provides protection for at least 5 months. Clinical trials have demonstrated that the risk of hospitalisation from RSV infection is reduced by almost 80% in infants who receive nirsevimab.
The clinical trial data on the efficacy of RSV immunisation products is available on the NCIRS - Respiratory syncytial virus (RSV) FAQs.
Infants and children less than 24 months old who have had prior laboratory-confirmed RSV infection are excluded from eligibility criteria to receive nirsevimab.
Infants and children less than 24 months old who have already received Synagis (palivizumab) and who meet the NSW Health RSV Prevention Program: Eligibility can receive Beyfortus™ (nirsevimab). Beyfortus™ (nirsevimab) can be administered 28 days after Synagis (palivizumab), instead of their next Synagis (palivizumab) dose. Synagis (palivizumab) should then be discontinued.
Data on the safety of RSV immunisation products is monitored by the TGA. The clinical trial data on the safety of nirsevimab is available on NCIRS.
AusVaxSafety the national active vaccine surveillance system, will also be monitoring the safety of RSV immunisation products to ensure their ongoing safety. For more information visit RSV vaccines | AusVaxSafety.
Additional information about the safety of RSV immunisation products is also available in the NSW RSV Prevention Program – Clinicians Guide.
Report all uncommon, serious, significant or unexpected adverse events following medication administration. To report a suspected adverse event, please download the National Adverse Events Following Immunisation (AEFI) Reporting Form and contact your local public health unit on 1300 066 055.
For more frequently asked questions about respiratory syncytial virus (RSV) visit NCIRS - Respiratory syncytial virus (RSV) FAQs.
Resources for pregnant women and parents about the RSV prevention program are available on
