SYDENY: Australia ordered 21 million courses of swine flu vaccine today — enough to cover the country’s entire population — as the World Health Organisation warned the pandemic was “unstoppable.” Although a vaccine is not expected to be available until at least September, federal chief medical officer Jim Bishop said the government hoped to launch a major immunisation programme in October to combat the progress of the virus.

Australia is already the worst-hit nation in the Asia-Pacific region, with almost 10,000 cases and 19 virus-linked deaths, and Bishop expressed concern that the “hard-edged” disease was now infecting young and healthy people.

“We are seeing a few people now thrown up that have other medical conditions being unwell, (but) also we are seeing a few people that were previously well but are severely affected by the disease,” Bishop said. “Almost all of those swine flu deaths have been in people with prior medical conditions which have been exacerbated but, as I said, there will be now some experience with unfortunately people who have been previously well,” he added.

Six people younger than 40 who had otherwise been healthy were on life support in Sydney, with A(H1N1) influenza damaging their lungs so badly they had to be put on special machines to oxygenate their blood, officials said.

The WHO said a vaccine should be available as early as September, warning that the pandemic was now “unstoppable,” with more than 90,000 cases reported, including 429 deaths.

Although a vaccine is not yet available, Canberra has commissioned pharmaceutical company CSL to manufacture it, following trials. “We need to do some trials to make sure it’s safe, so we’re saying by October we should be able to start a programme, but that depends really on manufacture being successful,” Bishop said.

He said 21 million doses would be enough to vaccinate everyone in Australia once over, or half the population if two courses were required, ahead of a “second wave” of infections.

“We’re more concerned about the second wave of this thing, which might be more severe than the first.” A US study released this week warned A(H1N1) could pick up genes from other flu strains that would enable it to be both highly virulent and contagious, or acquire mutations enabling it to be resistant to the anti-viral drug Tamiflu.