New strain of bird flu found that 'sidesteps' vaccines

SCIENTISTS have discovered a new strain of bird flu that appears to sidestep current vaccines.

It is infecting people as well as poultry in Asia, and some researchers fear its evolution may have been steered by the vaccination programmes designed to protect poultry from earlier types of the H5N1 flu.

The discovery by Yi Guan, of Hong Kong University, and colleagues is reported in today's issue of Proceedings of the National Academy of Sciences.

The new variant has become the primary version of the bird flu in several provinces of China and has spread to Hong Kong, Laos, Malaysia and Thailand, the researchers report.

It is being called H5N1 Fujian-like, to distinguish it from earlier Hong Kong and Vietnam variants.

"We don't know what is driving this," said report co-author Dr Robert Webster, of St Jude's Children's Research Hospital in Memphis, Tennessee.

While the new virus has infected people, there is no evidence that it can pass easily from person to person, Dr Webster said. He added that new vaccines would now have to be developed.

Dr Michael Perdue, of the World Health Organisation (WHO)'s Global Influenza Programme, said the new variant doesn't indicate any increased risk for people "other than the fact it seems to be pretty widespread."

The virus was continuing to change, he added.

Dr Perdue said the WHO is working with the Chinese ministry of health to develop a vaccine for the new form of the virus.

The H5N1 flu has devastated poultry in China and several other south-east Asian countries and has claimed more than 150 human lives. Most of the people affected lived close to flocks of chickens or other poultry. Public health authorities fear the virus will mutate into a form that can spread easily among people.