The British government has ordered two to three million doses of this vaccine and is soon to announce which company among those who tendered has been awarded the contract.
Researchers led by Yi Guan, of Shantou University, China, who studied the avian flu in China and South East Asia said that the diversity of the viruses are such that the vaccine may be fruitless, reported Times Online.
Bird flu has killed at least 88 people in Asia and Turkey since 2003, according to the World Health Organization. Birds carrying the virus have also been detected in Italy, Greece and Nigeria.
The researchers indicated that the virus has been spreading in an uncontrolled fashion in China for the past decade, has crossed into Vietnam on three occasions and may be spread by "carrier" poultry that show no symptoms.
The team in their research published in Proceedings of the National Academy of Sciences concludes: "The antigenic diversity of viruses currently circulating in South East Asia and southern China challenges the wisdom of reliance on a single human vaccine for pandemic preparedness."
The British government's other defence against the pandemic flu is the antiviral drug Tamiflu, of which it has ordered 14.6 million courses. A spokeswoman for the department of health said that almost five million had been delivered so far, the report said.