Parents are advised to look out for signs of breathing problems in young children over winter, with a report highlighting the deadly risks from a mostly unknown seasonal virus.
The report found RSV, or respiratory syncytial virus, is responsible for the hospitalisation of about 12,000 babies under 12 months each year.
That number climbs to over 15,000 for children under five, which is eight times higher than the numbers hospitalised for the flu.
The virus is relatively unknown within the community, with Australia's first RSV Awareness week launched on June 4.
Children who contract the virus can suffer long term health complications including allergies and asthma.
In infants, symptoms include a runny nose, coughing, sneezing, wheezing, loss of appetite, lethargy, and irritability.
The report, funded by pharmaceutical giant Sanofi, found low levels of awareness of the virus within the community, despite the dangers.
Healthcare advisory company Evohealth was involved in the report, with managing director Renae Beardmore saying growing awareness of the virus is showing the scale of its impact on Australian children.
She said while most children will contract the virus by the age of two, some will suffer complications such as bronchiolitis and pneumonia.
"This is a virus that often went undiagnosed due to lack of awareness, monitoring and reporting, which has recently changed," she said.
"Now that we are starting to understand the scale of the RSV in Australia, it's time to act to reduce the burden of the virus on children, parents and hospitals."
The report found the common and unpredictable virus is costing the healthcare system about $200 million a year.
Last month, the Therapeutic Goods Administration gave the green light to a newly approved nasal swab able to diagnose COVID-19, influenza, and RSV within 15 minutes.
Channel Nine broadcaster Karl Stefanovic and his wife Jasmine are involved in the RSV awareness week campaign, after their young daughter Harper suffered complications from the virus last winter.
Stefanovic became emotional on air last year when he described their fear as their two-year-old daughter was hospitalised.
The Immunisation Foundation Australia is hopeful RSV will soon become a vaccine-preventable illness, with founder Catherine Hughes's daughter also impacted by the virus.
"It's important that caregivers know the signs that may indicate severe disease, trust their gut, and seek medical attention when it's needed," she said.