US officials should help drug companies speed up the supply of swine flu drugs and vaccines, making at least some shots available by mid-September, White House science advisers said.

Calling the H1N1 pandemic "a serious threat to our nation", they also urged the US Food and Drug Administration to quickly decide on new, intravenous formulations of flu drugs, including current drugs such as Roche AG's Tamiflu and GlaxoSmithKline's Relenza but also BioCryst Pharmaceuticals' experimental drug peramivir.

The news sent BioCryst's shares soaring more than 25 per cent to $12.60 as trading closed on Nasdaq.

The President's Council of Advisors on Science and Technology said the Department of Health and Human Services should tell manufacturers to begin to "fill and finish" H1N1 flu vaccines right away -- putting them into vials for shipment.

"Such a decision would need to be taken almost immediately," the group said in a report.

Most experts believe people will need two doses of the vaccine, delivered at least two weeks apart, to develop full immunity to the new H1N1 flu.

Pandemic H1N1 is circulating widely and experts expect it to worsen in the northern hemisphere's autumn as students return to school. The council's report says the virus, although moderate, could infect 30 per cent to 50 per cent of the US population this year, put 1.8 million into the hospital and kill anywhere between 30,000 and 90,000 people.

The numbers reflect various estimates published since H5N1 avian influenza emerged as a pandemic threat in 2003 and are based on previous flu pandemics, not on anything unique the H1N1 virus is doing.

Seasonal influenza kills an estimated 36,000 Americans every year and puts 200,000 into the hospital. Between 5 per cent and 20 per cent of the population gets the flu in average years.

But because this virus is new, more people are susceptible to it and the World Health Organization has been predicting for months now that a third of the world's population, or 2 billion people, will likely become infected.

Vaccine rush    

So governments are rushing to order vaccine. Last week the US Department of Health and Human Services said only 45 million doses of the new H1N1 vaccine would be on hand for mass vaccination to start in mid-October, instead of 120 million previously forecast, with 20 million a week due after that.

"We still think mid-October is a good target for a major production to roll off," HHS Secretary Kathleen Sebelius told reporters in Atlanta, where she was visiting the US Centers for Disease Control and Prevention.

Five companies make swine flu vaccine for the US market -- AstraZeneca's MedImmune unit, CSL, GlaxoSmithKline, Novartis and Sanofi-Aventis,

The Council also recommended a quicker decision on intravenous versions of flu drugs. People who are seriously ill can only be given drugs intravenously.

Tamiflu, a pill known generically as oseltamivir, is made by Roche under license from Gilead Sciences Inc Relenza, which is inhaled, is known generically as zanamivir and is made by Glaxo under license from Biota Inc.

Drugmakers are working on intravenous formulations of both and BioCryst is working to perfect peramivir, which is designed to be given intravenously.

The advisers said the CDC should strengthen guidelines on when these drugs should be given. Tamiflu and Relenza can treat and prevent all types of influenza A if given soon enough but the World Health Organization says they should be saved for use only by people who are at high risk of serious complications or death, such as pregnant women and asthma patients.

And the panel said the government should take advantage of the pandemic to improve flu surveillance. – Reuters