The World Health Organisation on Friday said it had "no doubt" that a successful vaccine against the new swine flu virus that could be made in a "short period of time" and in large quantities.
"We have no doubt that making a successful vaccine is possible in a relatively short period of time," said Marie-Paule Kieny, WHO Director of the Initiative for Vaccine Research.
Availability would take "four to six months between the time the virus is isolated to the availability of the first dose," she told reporters.
Kieny said a vaccine would be easy to produce using traditional methods of developing and producing vaccines, as well as more complex reverse genetic technology.
Dozens of manufacturers around the world, in both industralised and developing countries, had been approached and were committed to produce a vaccine against the new influenza A(H1N1).
"The main capacity is in Europe and North America but there are serious manufacturers in other parts of the world, in Asia in particular," she added.
"They still don't have the material that will allow them to start but they are already putting things in place that will allow them to do so as soon as possible."
The volume produced was still uncertain said Kieny. But her "best estimate is that there would be around one to two billion doses minimum available in one year."