"This incident exposes problems in our scientific research institutes," Vice Health Minister Jiang Zuojun said yesterday.

Comments by Jiang and other officials followed confirmation on Tuesday by the Ministry of Health that the country's first human case of H5N1 bird flu occurred in November 2003, two years earlier than previously thought.

Research institutes were not required to report infectious diseases until December 2004, when the law on prevention and control of infectious diseases was revised to include bird flu as a disease that must be reported, Jiang said.

"In the future, scientific research institutes must improve communication and contact with our disease prevention organizations," he said.

Jiang pointed out that it took time for researchers to identify the disease in 2003 during the SARS outbreak when diagnosis methods for emerging diseases were poor.

They had to be cautious in the DNA sequencing and epidemiological and genetic studies of the virus, he said. Jiang gave assurances that it was the only case that failed to fit the symptoms of SARS, adding they had no evidence of other bird flu cases before 2003.

The ministry's confirmation on Tuesday followed a letter published by eight Chinese scientists in the June 22 issue of The New England Journal of Medicine saying the virus had been isolated in a 24-year-old man who died in Beijing in 2003.

The man, surnamed Shi, became ill with pneumonia and a respiratory illness and died four days after being hospitalized. Attention at the time was focused on SARS. The man was misdiagnosed with SARS.