Ten Years to Develop an Effective Bird Flu Vaccine
Bird flu experts meeting in Paris at the First International Conference on Avian Influenza in Humans were told by leading virologists that it could take 10 years to develop an effective bird flu vaccine.
Dr David Fedson, a retired professor of medicine, told the conference that there were well-documented problems with the H5N1 virus when it came to making a vaccine.
Scientists normally grow such a vaccine from an inert form of a virus, using chicken eggs as their favourite growing medium.
According to Dr Fedson, who also worked for a number of years in the vaccine manufacturing industry, the vaccine produced from H5N1 was proving particularly difficult to grow up. It was also proving ineffective at stimulating an immune response that would give a person a good defence against bird flu.
He also told BBC News, that right now, worldwide, they can produce 300 million doses of seasonal flu vaccine, but it turns out that the H5N1 vaccine is so poorly immunogenic and replicates so poorly that they could immunise globally, with six months of production, about 100 million people.
