Fergus Walsh visits the Novartis cell culture manufacturing plant in Germany
The first doses of an H1N1 swine flu vaccine have been produced in Europe - but it will be around two months before any is distributed.
The doses were produced by Novartis at a plant in Marburg, Germany.
The vaccine was made in cell culture, a much faster method than the traditional way of growing it in eggs.
But Novartis said although the vaccine is ready, the first batch will not be used, as it was created using the wild type strain of H1N1.
All large scale vaccine production around the world will use a slightly modified "reassortant seed" virus.
This was provided by health officials in the US and is optimised to grow rapidly in hens eggs, which is the traditional means of creating flu vaccine.
Novartis decided to press ahead with work using the wild type strain because it received this form of the virus several weeks earlier.
What the company has effectively done is to prove that it is possible to make a vaccine.
Now work will focus on creating a vaccine from the seed virus.
So although Novartis is claiming to have created the first swine flu vaccine, it will not be until clinical trials are completed on a vaccine made from the seed virus and the first doses are delivered, that the race to get a vaccine will truly have been won.
The company said it had orders from 35 governments for its H1N1 pandemic flu vaccine.
None of these is from the UK, which already has contracts with two other manufacturers for enough vaccine for the entire population.
With the adjuvant vaccine we have developed there's a good chance that you will be protected even if it comes back in a different form
Dr Andrin Oswald Novartis Vaccines
The majority of these will be provided by GSK while the remainder will come from Baxter, using the same rapid, cell culture process as Novartis.
Last week the chief medical officer for England, Sir Liam Donaldson he hoped to receive the first doses of H1N1 vaccine "by the end of August".
Ministers have repeatedly said they expect to have enough doses for half the UK population by the end of the year.
But despite the optimism, there is a need for some caution when predicting when the first vaccines will be ready.
None of the manufacturers has begun clinical trials of the H1N1 vaccine.
These will test whether the jab is safe, what dose is required, and whether people will need one or two injections.
The working assumption is that two jabs will be needed, probably spaced three or so weeks apart.
Until the yield and dosage is known, it is impossible to be sure when, and in what quantity, the doses will come.
Novartis is adding an adjuvant, or booster chemical to its H1N1 jab.
Dr Andrin Oswald, the CEO of Novartis Vaccines, said this could prove valuable: "I think the the virus still has a risk of mutating further and becoming more aggressive.
"So with the adjuvant vaccine we have developed there's a good chance that you will be protected even if it comes back in a different form in the Fall."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.