A vaccine will soon be available for a highly contagious virus that caused thousands of Hunter-New England people to seek medical attention last year.
The Therapeutic Goods Administration has approved Australia's first vaccine for respiratory syncytial virus, also known as RSV.
The vaccine will be available only for people aged 60 and over.
A federal Department of Health statement said the TGA's approval was "the first step towards supply".
"Further details on supply and cost will be made available in due course," the statement said.
Professor Peter Wark, a senior research fellow at Hunter Medical Research Institute (HMRI), said there were three vaccines for RSV that showed "promising results" in trials.
"It's possible they will be recommended for a broader range of individuals, based on those results," Professor Wark said.
NSW Health data shows more than 4000 cases of RSV needing medical attention in Hunter-New England last year. The highest number of cases - 895 - was in June.
Hunter cases of RSV surged 10-fold last year, in line with the rest of the country, as viruses re-emerged following pandemic lockdowns and social distancing laws.
Across NSW, more than 45,000 positive RSV lab tests were recorded. This included about 9000 people aged 60 and over.
Young children, who aren't eligible for the vaccine, were the most prominent age group to need medical attention for RSV infection last year.
This included almost 25,000 children aged 0-4 in NSW.
Professor Wark said vaccinating young children for RSV was "not really an option because they don't mount an effective immune response".
"Very young children are at greatest risk in the first six months of life or if born premature."
The three RSV vaccines were "being trialled in at-risk women, so if you vaccinate mum the antibodies can be transferred to the baby".
Professor Wark said RSV could cause "a nasty acute illness".
"It has a tendency to go into the lungs," Professor Wark said.
"Every winter it's responsible for admissions to hospital with pneumonia and worsening of underlying lung diseases, particularly asthma and COPD."
The GlaxoSmithKline vaccine - named Arexvy - has already been approved for use in the UK, European Union, US, Canada and Japan. It is a protein-based vaccine given as a single dose.
Professor Robert Booy, a University of Sydney infectious diseases expert, said RSV infection "can have a significant impact on the health of older adults, including those with existing medical conditions".
"Most people view RSV as an illness that mainly affects children. Its impact on older adults, especially for those with underlying medical conditions, has fallen under the radar," he said.
Professor Wark said most older people "get a relatively mild illness from RSV".
"But it can cause more severe respiratory problems," Professor Wark said.
"Very young children and older people are particularly susceptible. As well, there's people with chronic lung and heart disease or immunosuppressed people."
He said RSV was the most common cause of the lung infection bronchiolitis in "very young children".
"That's the most common reason to be admitted to hospital in the first year of life with breathing difficulties."
