The number of H1N1 flu cases in Australia has doubled in the past day to 59. The federal government has warned that the H1N1 influenza A virus is spreading fast. Health experts say its rapid transmission coincides with the southern hemisphere's traditional winter flu season.
The H1N1 flu has been confirmed in most Australian states and territories. The epicenter of the outbreak is in Victoria, where a group of children are among those being treated.
Virus origin unkown
Tests have yet to reveal if the infections in Australia have been imported from other countries or whether the virus has started to spread among those who have not traveled overseas.
In New South Wales, health agencies have been criticized for not quarantining hundreds of passengers on board a cruise ship where 14 people were diagnosed with the virus, commonly known as swine flu.
Although some of those who disembarked the vessel in Sydney had complained of being ill, they were allowed to travel home.
Three crew members on the Pacific Dawn have shown flu-like symptoms. Authorities have diverted the cruise liner, which left Sydney bound for the Great Barrier Reef, to an island near the Queensland city of Cairns, where the patients will be tested for flu.
The virus' spread in Australia has come at the start of the southern hemisphere's annual flu season.
Country is preparing for 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," Rawlinson said. "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."
In an attempt to stop the virus spreading to Tasmania, children who have recently traveled to Mexico, the United States, Canada, Panama or Japan have been told to stay away from schools and childcare centers for seven days. Those countries have seen the largest number of cases.
Health screening intensifies
Officials say they will intensify health screening measures at airports and ports.
Australia's federal health minister, Nicola Roxon, says the number of confirmed swine flu cases will likely rise significantly in the coming days.
Worldwide cases of the virus have reached almost 13,000 Tuesday in 46 countries. Nearly 100 people have died, most of them in Mexico, where the outbreak began last month.
Elsewhere in the Pacific, Singapore reported its first case of H1N1, a woman who had just returned from a visit to the United States.