By Phil Mercer
BBC News, Sydney
Professor Bill Rawlinson, medical virologist, is tracking swine flu's spread
The number of swine flu cases in Australia has doubled in the last day to 59.
The government warned that the virus, spreading fast, has been confirmed in most Australian states and territories.
Health experts have said its rapid transmission was coinciding with the southern hemisphere's traditional winter flu season.
The epicentre of the outbreak is in Victoria, where a group of children are among those being treated.
In New South Wales health authorities have been criticised for not quarantining hundreds of passengers on board a cruise ship where 14 people were diagnosed with swine flu.
Although some of those who disembarked the vessel in Sydney had complained of sickness, they were allowed to travel home.
The virus's spread in Australia has come at the start of the southern hemisphere's annual flu season.
Professor Bill Rawlinson from Sydney's Prince of Wales hospital says the country is preparing for an onslaught.
"It is of concern because as we go into winter that is when we see our peak of flu and I think that is why we are all gearing up to deal with this problem and why public health authorities as well as the laboratories as well as clinicians, emergency departments are all putting in place practices that have been developed over other outbreaks such as Sars and the H5 avian strain," he said.
In an attempt to stop the virus spreading to Tasmania, students and toddlers who have recently travelled to Mexico, the United States, Canada, Panama or Japan have been told to stay away from schools and childcare centres for seven days.
Australia's federal health minister, Nicola Roxon, has said the number of confirmed swine flu cases was expected to rise significantly in the coming days.