BEIJING, Aug. 10 (Xinhua) -- Chinese government officials have blamed a lack of communication between researchers and health officials for the delay in confirming the mainland's first human case of bird flu.

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

Research institutes were omitted from legal requirements 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 by law be reported, he said.

"In 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 cases before 2003.

The Ministry of Health confirmed Tuesday that the country's first human case of H5N1 bird flu occurred in November 2003, two years earlier than previously thought.

A letter published by eight Chinese scientists on June 22 in the New England Journal of Medicine said 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. China was then in the aftermath of SARS, and the case was initially thought to be a SARS case. However, laboratory tests for SARS proved negative.

Parallel laboratory tests, carried out in collaboration with the World Health Organization (WHO), later confirmed it was a human case of bird flu.

"This is the first human infection confirmed in the world in the current H5N1 virus cycle," said Roy Wadia, WHO Beijing office spokesman.

Before the case was revealed, China's first official human case of bird flu was thought to have occurred in November 2005. Nineteen human cases have been confirmed since, including 12 deaths. Enditem