Bid to end confusion over bird flu strains
International body to standardise the classification of viruses after scientists gave one variant four different names
An international working group will be set up to standardise the naming of avian influenza viruses in response to confusion caused by the naming of an H5N1 variant in a controversial paper co-authored by Hong Kong scientist Guan Yi.
The decision was made after a four-day roundtable discussion attended by a joint mission representing the World Health Organisation, the Food and Agriculture Organisation and the World Organisation for Animal Health, as well as scientists from WHO collaborative laboratories and their Chinese counterparts.
David Heymann, the World Health Organisation's acting assistant director-general for communicable diseases, said yesterday the 'Fujian-like' virus identified in the paper published by Hong Kong-based scientists Dr Guan and Malik Peiris, and US scientist Robert Webster in October was not a new strain.
The strain was found last year and had been given four different names by scientists, he said.
'This newly identified group is not so newly identified. It has been circulating in the world since 2005. There have been animal infections with this virus and there has also been human infection,' said Dr Heymann.
Keiji Fukuda, co-ordinator of the WHO's Global Influenza Programme, said the strain evolved from an older virus in 2004 and confirmed it had been given four different names.
'We have confusion because Guan Yi's group called the strain Fujian-like virus, another group called it clade 2.3, another group called it clade 3, and another group called it waterfowl virus,' he said.
Dr Heymann said a working group consisting of scientists from different regions, including China, would work on a standardised naming system to avoid similar confusion in the future.
China had provided information and sequencing data about the strain to WHO, he said.
The paper published in the US-based Proceedings of the National Academy of Sciences suggested the variant might have become dominant and that China's massive vaccination programme for poultry had failed, or even made the strain resistant to the vaccines.
However, Dr Fukuda and other members of the mission visiting China said there was no evidence that the emergence of the strain had resulted from the vaccination programme.
'It is clear that this vaccine does not cause the emergence of this virus. We do not believe it is the situation,' he said.
Dr Fukuda added that it remained unclear how widespread the strain had become.
'We all agree that it is found in some parts of southern China and has been identified this year in Laos and Malaysia,' he said. 'But we also don't know how common it is in other parts of China, how common it is in other countries.'
However, Dr Fukuda stopped short of comment about whether the paper published by Dr Guan was incorrect.
'The article raises a number of issues that really should be investigated,' he said.