Hong Kong - Researchers in the United States believe they have found an easily-produced vaccine for the killer H5N1 bird flu that could halt a feared pandemic, a media report said Monday.

Dr David Ho of the Aaron Diamond Aids Research Centre in New York says the vaccine would be "easy to produce, fast to produce and as broadly protective as possible", according to Hong Kong's South China Morning Post newspaper.

Ho spoke to the English-language daily during a lecture visit to Hong Kong, where the first human cases of H5N1 infection were recorded in 1997, when six people died.

The report said tests on mice had shown the animals had produced the antibodies necessary to fight the disease, which has killed more than 160 people since outbreaks in Asia in 2003 spread throughout the world.

While the virus has decimated poultry flocks, it cannot yet transfer efficiently enough between humans for it to spark a pandemic.

But as the virus is mutating all the time, health experts fear the day when it does become easily transmitted is not far off. A pandemic would then claim millions of lives, they warn.

The report says Ho claims to have overcome the problem of manufacturing enough of the vaccine to get it out fast enough to halt a pandemic.

It said the process involves copying genetic material from flu virus protein and combining it with antibodies to help stimulate the immune system.

The technique could be easily applied to other forms of flu virus too, it added.

"These days gene synthesis and cloning can be done in a week so you just substitute the genes and use the same technology," Ho was quoted as saying.