Scientists in Hong Kong have reported concern about a strain of bird flu that research has shown to be present in about two per cent of chickens there. They fear the strain's widespread presence in the region increases the chance it will 'jump' to humans.
The strain — called H9N2 — is different to H5N1, the strain that killed 24 people earlier this year and led to the culling of more than 100 million domestic birds. As H9N2 is less likely to kill chickens than H5N1, the chance of it passing between species or mutating into something more dangerous is greater, say the scientists, from the University of Hong Kong.
H9N2 has been detected in pigs and at least three people in Hong Kong since 1999. The researchers are concerned that pigs can act as 'mixing vessels' in which different strains of virus can mix and swap genetic material, creating a new form more dangerous to humans.