Healthy birds could spread AI

The researchers' findings suggest that food markets or farmers' markets that have live poultry may be a source for avian influenza infection, with healthy live birds carrying the virus.

This information is in contrast to general warnings given across the globe that people should avoid contact with sick or dead birds.

The study showed that a patient may have been infected with highly pathogenic avian influenza virus H5N1 at a food market that had live birds in Guangzhou, in People's Republic of China. In spite of birds appearing healthy, virus genes were detected in a goose cage at the market, and one person in the poultry business at the market had a neutralising antibody against H5N1.

According to the researchers, this case from Guangzhou is not an isolated event. Five patients with H5N1 infection with no history of exposure to diseased or dead birds before the onset of avian influenza have been reported in the People's Republic of China; four of these visited markets that had live birds.

The study was undertaken by the Guangzhou Center for Disease Control and Prevention, Guangzhou, People's Republic of China.