A spokesman for China's Ministry of Health on Tuesday confirmed there is no evidence to suggest that China's bird flu virus has mutated to a form that can spread between humans.

"We have not found any proof of a match between the avian flu virus and the human flu virus," said Mao Qun'an in an interview with Xinhua.

Studies show that the avian flu virus isolated from China's human cases still bears distinct avian features far removed from the human flu virus.

There are no geographical or chronological links between the 12 human cases found on the Chinese mainland since last October.

All the victims developed severe symptoms of pneumonia, most of which soon led to respiratory failure and deterioration of other organs such as the heart, liver and kidneys, he said.

"The reasons for the high mortality rate in areas where no bird flu was found was due to insufficient knowledge of grassroots health workers as well as patients, which resulted in belated detection and treatment," Mao told Xinhua.

More research has been carried out by scientific teams to trace the origins of the bird flu virus, and training of rural grassroots health workers has been improved, according to the spokesman.

On the other hand, the ministry has called on more publicity to raise public awareness of the disease, telling them to have less contact with sick or dead poultry and to report symptoms quickly, he said.

China has announced 12 human cases of bird flu since last October, resulting in eight deaths. Globally, the World Health Organization (WHO) has recorded 170 human cases, including 92 deaths.

(Xinhua News Agency February 22, 2006)