The main reasons for human infections are a lack of effective bird flu surveillance in villages and towns as well as delayed reporting of outbreaks, according to the Ministry of Health.

Spokesman Mao Qun'an offered the explanation yesterday following the ministry's announcement of China's eighth human case of H5N1 bird flu on Monday night.

A 6-year-old boy, surnamed Ouyang, in Guiyang County of Central China's Hunan Province is reported to be in a critical condition in hospital.

Experts have found ill chickens in the area where the boy lives, but have yet to test whether they are infected with H5N1.

Most of the human cases on the Chinese mainland were first reported in big hospitals before investigations were conducted in the patients' villages to find the source, Mao said.

The probes have usually led to the discovery of poultry epidemics where they lived but which were not reported, he said.

At village clinics or township hospitals, the human infections were typically diagnosed as pneumonia from unknown causes because doctors there are not qualified to detect bird flu infections.

As a result, the best window of opportunity for treatment was missed, leading to the three fatalities in China, he said.

The monitoring and reporting system of infectious diseases now covers 66 per cent of China's township hospitals, and more than 90 per cent of hospitals at county levels or above.

More village doctors will be encouraged, and financially supported, to join the system, Mao said, adding that all hospitals have been asked to scrutinize pneumonia cases without clear causes.

Mao said that controlling the virus would be one of the health ministry's top priorities in 2006.

"What we're doing is to seek to strengthen supervision in the health system, to detect infectious diseases and monitor epidemics as early as possible," he said.

"In the new year we'll especially emphasize the effort to prevent and control bird flu among humans."

One of the most urgent tasks is to improve the ability of health authorities to monitor developments at the grassroots level, according to Mao.

In each of China's tens of thousands of villages, qualified people will be picked and charged with monitoring and reporting the epidemics situation.

"We need to do this before a possible mutation of bird flu," he said.

Complacency warned against

Mao warned the people against complacency in the fight against bird flu.

"We cannot lower our guard in the slightest degree against the risk of bird flu triggering a new epidemic," Mao said.

"As long as there are still outbreaks among animals, as the health authority we cannot say bird flu is already past its peak."

In particular he warned against the nightmare scenario of bird flu starting to spread from human to human, rather than the current transmission pattern from bird to human.

"Even though we haven't yet detected cases of spread among humans, we can't ignore the potential threat," he said.

China has the world's biggest poultry population, combined with often primitive farming conditions where humans and animals live in close proximity.

The bird flu virus has killed more than 70 people throughout Asia since 2003, the majority of them in Vietnam.

European nations and world health experts are currently also on higher alert after Turkey reported 13 people had been infected with the disease, including two who have already died.

Editor: Yan