A major investigation is underway after listeria outbreaks were detected in three Aussie states.
Nine cases of the potentially deadly bacteria have been diagnosed, including five cases between three Queensland hospitals.
Listeria comes from eating contaminated foods, including processed meats and soft cheeses.
It can lead to listeriosis, an illness that can be dangerous for pregnant, elderly, or immunocompromised people.
A spokesperson from Mater Hospital in Brisbane told 9news.com.au in a statement "a small number of listeria cases" had been detected at health facilities in south-east Queensland.
"Affected patients have been treated in accordance with best practice," the spokesperson said.
NSW Health issued an urgent warning earlier this month after several confirmed cases of listeria infection were confirmed.
Victoria's health department has also confirmed there have been listeria cases in the state.
The Mater Hospital spokesperson said the federal government's OzFoodNet has co-ordinated a national investigation into the outbreak following cases in NSW and Victoria.
Dr Michael Bonning, from the NSW Australian Medical Association(AMA), told Weekend Today that disease investigation specialists would be racing to find the source of the outbreak.
"It's very unusual that we would see this many cases, this quickly together, and especially because they're across multiple hospital sites and in fact multiple sites around a state," he said.
"We need to know where they're coming from and why."
Bonning said listeria wasn't necessarily a type of bacteria associated with hospitals.
"Listeria can be found in our soil, it can be found in the environment, it can be found in foods, especially raw and unprocessed foods," he said.