China has confirmed an outbreak of H5N1 bird flu in wild birds in the remote far-western Qinghai province and in Tibet, with about 400 wild birds having been found dead recently.
The governments of Qinghai and Tibet have disinfected the region where the birds were discovered, and no affected domestic poultry have been found.
Thousands of birds were killed in an outbreak of the H5N1 strain at Qinghai Lake last May. The H5N1 strain of the virus has since been found in Europe, Africa and the Middle East.
China has reported at least 18 human infections of the H5N1 strain, 12 of which have been fatal. It has reported almost 40 outbreaks of bird flu in poultry across a dozen provinces over the past year.
Epidemiologists fear that bird flu could mutate into a form where it could pass easily among humans, potentially triggering a pandemic.
An outbreak of H5N1 in the Qinghai capital of Xining, where more than 120 wild birds were found dead, was reported at the beginning of the month.
Health experts see China as being particularly at risk because of its huge human population and many poor, remote areas.