Britain's health secretary warned Thursday the country could soon face more than 100,000 daily cases of swine flu, while fears linked to the virus soared in Argentina after the death toll nearly doubled.

The warning from British Health Secretary Andy Burnham came as news emerged that the A(H1N1) virus has now spread to all 27 countries in the European Union, with Malta reporting its first two cases.

Authorities in Australia, Asia-Pacific's worst-hit nation, also told parents not to panic after the country announced its first child death linked to swine flu, while Argentina's government came under fire for its response to the pandemic.

Burnham said 100,000 cases a day could occur in Britain, which has Europe's highest number of reported cases, by the end of August if the current rate of infection is maintained.

"Cases are doubling every week, and on this trend we could see over 100,000 cases a day by the end of August, but I stress this is only a projection," Burnham told the lower house of parliament.

Britain now had nearly 7,500 cases of swine flu, he said, with hundreds of new cases being confirmed every day.

Health officials have said Britain is abandoning a policy of trying to stop the flu spreading and instead focusing on patients most susceptible to it, such as obese people or those suffering from asthma or breathing problems.

Three people have died in Britain after contracting swine flu, and all had "underlying health problems."

The latest numbers from the World Health Organisation, released on Wednesday, showed 77,201 reported swine flu cases worldwide, with 332 deaths.

Argentina has surpassed Canada as the country with the most swine flu-linked deaths after the United States and Mexico.

Swine flu fears in the South American nation have been aggravated by the government's refusal to declare a state of emergency even as the death toll nearly doubled from 26 to at least 43.

New Health Minister Juan Manzur avoided precise numbers at his first press conference on Wednesday, finally settling on "between 43 and 44" as the number of deaths.

The virus spread in Argentina at a time when the government and public were distracted by a campaign for mid-term legislative elections held Sunday.

But flu fears have taken off since Sunday's election, as public and media attention has shifted from politics to the mounting number of deaths and infections.

On Monday, pharmacies ran out of masks, as advice about how to avoid the flu suddenly replaced the drama of President Cristina Kirchner's electoral defeat as the top topic of conversation.

In Australia, authorities on Thursday said parents should not panic after the death of a three-year-old boy with swine flu.

Health Minister Nicola Roxon called the death a "tragedy," but emphasised the virus was mild in most cases.

Separately, Sydney immunisation specialist Robert Booy said swine flu was likely to kill twice as many children over the next 12 months as regular influenza.

The professor estimated 10-12 children could die from the virus, compared with five or six from normal flu strains in a typical year.

Meanwhile, an Australian athlete who was due to compete at the world student games in Serbia has been infected with swine flu, Serbian health authorities said Thursday.

The 25th Universiade, or world student games, opened in Belgrade on Wednesday night and includes around 10,000 athletes, coaches and other officials.

In addition to Malta, Uganda and the US Pacific territory of Guam have also announced their first cases.

"It was a matter of when, not if," Malta's Parliamentary Secretary for Public Health Mario Galea said of his country's first cases.