RSV in WA: A Record-Breaking Season Meets Strong Immunisation
Western Australia is navigating what could be its worst respiratory syncytial virus (RSV) year on record. Latest health data show 11,551 RSV cases reported to the Department of Health as of Monday, just 104 cases shy of the peak set in 2022. While the numbers paint a worrying picture, the persistence of a robust immunisation program is helping to mitigate more severe outcomes, particularly in young children.
Immunisation Uptake and Its Protective Effect
Despite a soaring autumn and winter RSV burden, hospital admissions related to RSV have remained slightly lower than last year. This trend is attributed, in part, to Western Australia’s free RSV immunisation program for infants and to maternal vaccination programs. Health researchers from The KIDS Institute, including infectious diseases clinician researcher Ushma Wadia, say the data suggest a protective effect from immunisation.
“It is children under five years of age, particularly those under two, who are most impacted by RSV,” Dr. Wadia noted. “We’re seeing more RSV notifications, but fewer children are being hospitalised, likely reflecting the protection provided by maternal RSV vaccination and nirsevimab for infants.”
WA now offers two layers of defense for the youngest residents: an infant RSV immunisation and a vaccine for pregnant women. The infant program began in 2024, with the maternal vaccine added this year, and more than 23,200 infants and pregnant women had been immunised by October 5 — about 263 more than the prior year.
Who Bears the Burden and What It Means
Nearly half of RSV cases involve children under five, underscoring the importance of protecting this vulnerable group. Ongoing research from The Kids Institute’s PATROL study aims to deepen understanding of how RSV spreads in communities and identify strategies to minimise transmission and severe outcomes.
RSV Versus Flu: The Seasonal Context
Against the RSV backdrop, influenza activity has also surged in WA, with flu case totals surpassing 30,000 over a recent weekend — a level not seen since federal records began in 2001. The current flu season is the third time cases exceeded 20,000, with a record 2019 tally previously standing as the high mark for flu in WA. Health experts caution that RSV trends are improving weekly, while influenza is at its peak and may peak again after school holidays when social mixing increases.
What To Expect Next
Experts expect RSV notifications and hospitalisations to continue showing weekly declines, even as the total case count remains high. For influenza, the trajectory remains more volatile, with continued hospital admissions likely for a while longer. Dr. Wadia urged the community to protect themselves and others by getting vaccinated against the flu if they have not already done so this season.
Key Takeaways
- WA is on track for a record RSV year, but hospitalisations are trending down thanks to immunisation programs.
- Maternal vaccination and infant immunisation provide protection during the most vulnerable early months.
- Public health surveillance, including PATROL, continues to inform strategies to curb transmission.
- Flu remains a major concern with rising case numbers; vaccination is strongly advised.
