Avian Flu Outbreak in China

A study in the 8 July 2005 issue of the journal Science of some of the birds found sick or dying on China's Lake Qinghaihu last spring shows that the birds were infected with the highly pathogenic strain of avian influenza, H5N1, and suggests that migrating birds could spread this strain throughout Asia and beyond.

The lake is a major breeding center for migrant birds that come from Southeast Asia, Siberia, Australia and New Zealand, according to Jinhua Liu and colleagues. In this "Brevia" article, the authors analyzed a variety of birds collected from the lake, whose physical symptoms were consistent with those observed in domestic geese and ducks infected with H5N1.

The researchers also isolated several H5N1 viruses from the birds and found that the genome sequences showed the hallmarks of a highly pathogenic strain of H5N1. The sequences didn't completely match the GenBank sequence data for known H5N1 genomes, implying that the segmented virus genome has undergone some rearrangement in birds overwintering in Southeast Asia.

Kathy Wren

6 July 2005