CHICAGO - The U.S. government is testing several potential bird flu vaccines for poultry, officials said on Friday, after more than 58 million chickens, turkeys and other birds have died in the nation's worst outbreak ever.
The trials, conducted by the U.S. Department of Agriculture's (USDA) Agricultural Research Service, are the first step in a lengthy process toward the possible use of vaccines to protect poultry from the lethal virus. There is no guarantee the government will ultimately approve their use.
Bird flu, also known as highly pathogenic avian influenza (HPAI), has killed hundreds of millions of birds around the world, raising interest in vaccines. The virus is largely spread by wild birds that transmit it to poultry.
Initial data from a U.S. study with a single dose of a vaccine are expected in May, while results from studies on two-dose vaccine regimens are expected in June, the USDA said.
If the trials are successful and USDA decides to continue development, it would take at least 18-to-24 months for a vaccine that matches the current virus to be commercially available, the agency said.
Governments have previously focused on culling infected flocks to control the virus due to concerns that vaccinations could mask the spread of bird flu and hurt exports to countries that have banned vaccinated poultry on fears infected birds could slip through.
The USDA said on Friday that its "current strategy of stamping out and eradicating HPAI... continues to be the most effective strategy because it works."
France said last week it pre-ordered 80 million doses of vaccines to be ready to begin a vaccination program in ducks in the autumn if final trial results are positive, the first member of the European Union to start such a plan.
(Reporting by Tom Polansek; Editing by Bill Berkrot)