GlaxoSmithKline said Thursday after the World Health Organization declared a global flu epidemic that it would be ready within weeks to begin large-scale vaccine production. Sanofi-Aventis also said it had started working on its own version. On Friday, Swiss pharma giant Novartis announced it had created an experimental vaccine that has not been tested in people. Novartis' vaccine was made via a cell-based technology that may prove faster than the traditional way of making vaccines, which relies on chicken eggs.
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Many rich countries like Britain, Canada and France signed contracts with pharmaceuticals long ago, guaranteeing them access to pandemic vaccine. WHO and others estimate that about 2.4 billion doses of pandemic vaccine could be available in about a year.
The likely scramble for vaccines will leave many people in poorer countries empty-handed.
So far, swine flu has been mostly detected in developed countries like the United States, Europe, Japan and Australia.
"We do not know how this virus will behave under conditions typically found in the developing world," WHO chief Dr. Margaret Chan said Thursday. She said the agency expects to see a "bleaker" picture as the virus makes its way to Africa and Asia.
WHO spokesman Gregory Hartl said officials were concerned people in poorer countries and those fighting other health problems like malaria, tuberculosis, malnutrition and pneumonia might be more susceptible to swine flu.
On Friday, WHO said that 74 countries had reported nearly 30,000 cases including 145 deaths. But so far, the virus appears to be mild. Most people don't need medical treatment to get better.
But the virus might have a more devastating effect in people with underlying health problems. About half of the people who have died from swine flu have had complications like asthma, diabetes, and obesity.
"Any population that has health challenges is potentially going to be at higher risk with H1N1 (swine flu)," Hartl said.
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In May, officials led by Chan and U.N. Secretary General Ban Ki-moon asked vaccine makers to save a portion of their production for poor countries. Chan was aiming to get 10 percent of the global pandemic vaccine supply reserved for poor nations.
Some companies have agreed to help. GlaxoSmithKline PLC offered to donate 50 million doses of pandemic vaccine to WHO for distribution to developing countries.