The race is on to develop a vaccine that is effective against the pandemic strain of swine flu before the flu season begins this fall in the northern hemisphere.
Estimates for when a vaccine will be available range from September to December.
But medical experts have warned against rushing the vaccines through trials, and in the meantime, countries must cope with rising cases of swine flu.
Britain's Department of Health launched a new website and call centre to deal with the increasing number of swine flu cases in the country.
Authorities estimate the number of swine flu cases in Britain has doubled in the last week to about 100,000 and officials are telling people not to go to a doctor if they have symptoms but instead to visit a new swine flu website or call a flu hot line.
People who need Tamiflu are being asked to stay home while a friend collects the drug for them at a designated "tamiflu collection site".
The Tower Hamlets Anti Virus Centre, located in East London, was the first Tamiflu collection site set up in Britain's capital.
It was opened about four weeks ago in June.
Tower Hamlets is one of the UK's worst affected areas for swine flu and Nurse Lesley Collins says that on a busy day about 350 people could walk through the doors of the clinic seeking treatment and collecting Tamiflu for friends.
Countries such as Britain, Greece, France and Sweden say they'll start using the vaccine as soon as it's green-lighted by the European Medicines Agency, the European Union's top drug regulatory body.
Drugmakers including Baxter International, GlaxoSmithKline PLC, Novartis and Sanofi-Pasteur have said their vaccines would be ready for testing soon.
Glaxo said it would only have limited data from human tests because governments want the vaccine quickly.
It has received orders for 195 million doses of the vaccines and expects the first shipments to be available from September.
British health officials have repeatedly said they will start vaccinating in August, as soon as the vaccine is approved by the European Medicines Agency.
Richard Vautrey, Deputy Chair of British Medical Association's GP Committee, says that despite the tight deadlines, the regulatory authorities will make sure that the vaccine is safe for use.
He says that drug companies have extensive experience in manufacturing flu vaccines in a "very short time scale".
Assuming the studies show the vaccine is OK, a big question is how much will be available and when.
Last week, the World Health Organisation warned that production is going slower than predicted, with the strains now in use yielding only about half as much of the main vaccine ingredient as is usual.
The spokesman for the Heath Ministry for the state of Thuringia in Germany said that his government has ordered 50 million doses of the vaccine.
"We are expecting to have it ready by autumn at earliest, by September or October. As soon as it is ready, it will be delivered and used up," said Thomas Schultz
However French Health Minister Roselyne Bachelot, said that she wasn't willing to estimate when the vaccine would be ready.
She said that the swine flu in its current form was not virulent enough to justify taking the risk with an unproven vaccine.
"We will want to have all the guarantees before offering the vaccination to our fellow citizens," Bachelot told reporters.
Meanwhile, US federal health officials said on Thursday that the new swine flu wasn't yet mutating to become more dangerous.
They said that they were closely tracking that as the virus continues to circle the globe.
Earlier this week, two Australian companies began the world's first human tests on a swine flu vaccine, giving injections to more than 500 people for a seven month long trial.
The tests, plus additional research from vaccine manufacturers, are key as governments decides when to offer swine flu vaccine to millions of citizens.
Britain's GlaxoSmithKline, Swiss-based Novartis AG and maker of the only nasal-spray vaccine, Maryland-based MedImmune will conduct their own studies in thousands of volunteers.
As the testing continues, many Britons remain wary of the planned vaccine.
Peter Abraham, a sign language interpreter who works in East London, said that he wouldn't get vaccinated because he felt his own body would take care of the virus.
Another woman said that she was planning to boost her immune system with vitamins.
AP