China is conducting lab tests to confirm whether a man died of bird flu in 2003, the Ministry of Health said on Monday.

A letter published by eight Chinese scientists in a June 22 issue of the New England Journal of Medicine said that the bird flu virus was isolated in a 24-year-old man who died in Beijing in 2003.

The ministry has made contact with the eight scientists, said Mao Qun'an, spokesman of the ministry.

The man, who became ill with pneumonia and respiratory disease on November 2003, died four days after being hospitalized. Since China was then experiencing the outbreak of the severe acute respiratory syndrome (SARS), the case was suspected a SARS case, but lab tests were negative for SARS.

However, the cause of his death was not clear, Mao said. Doctors and scientists conducted studies on the specimens taken from the man over a period of two years, and compared the virus isolated from the man's samples with influenza A (H5N1) viral strains from China and other countries.

Their findings suggest that the man might have died of the bird flu, Mao added.

"In accordance with World Health Organization and China's diagnostic standards for human avian influenza, parallel laboratory tests are needed for further confirmation," he said.

The Chinese Center for Disease Control and Prevention is conducting the tests, and the ministry will keep the WHO updated, added Mao.

China reported its first human bird flu case in November, 2005. Up to now, China has reported 19 cases, among which 12 have died.

Editor: Yan