Authorities must take action to meet the immense challenge of handling public health and emergency response issues during the 2008 Beijing Olympics, a World Health Organization (WHO) official warned yesterday.

"The influx of visitors in 2008 will add enormous challenges to daily surveillance and reporting mechanisms regarding infectious, chemical, environmental and non-communicable diseases," Henk Bekedam, WHO Representative in China, told China Daily.

"To tackle any possible public health accidents, a strong surveillance system must be in place as soon as possible, not only focusing on the three-week long Olympic Games, but also the months before," Bekedam noted.

The country has greatly enhanced its surveillance system following the SARS outbreak, which attacked Beijing in 2003 and 2004, and the recent bird flu problem, he added.

But he also warned China must strengthen epidemic surveillance capacity building at lower levels.

"By this I mean that people who first find infectious disease outbreaks are able to report them in a timely fashion," he said on the sidelines of the Workshop on Public Health Safety and Emergency Response for the Beijing Olympic Games.

Commenting on the threat posed by bird flu, which has killed 10 people so far in the country, Bekedam said that "if the virus fails to become very easily transmittable between human beings by that time, even if you find one or two human cases in China in June during the Olympics, it will make no difference at all."

"We will do our best, depending on our surveillance system, to monitor the symptoms of any infectious diseases, quickly issue alarms and take effective emergency response measures," said Wang Yu, director of Chinese Centre for Disease Control and Prevention.

China has established the world's biggest reporting system for dozens of infectious diseases, Wang said, before adding that in the coming two years, it will become an increasingly urgent task for China to set up a surveillance system and an information-sharing network.

Beijing has already established a comprehensive prevention and control system, including surveillance and response, to contain new or major outbreaks of infectious diseases, said Liang Wannian, deputy director of Beijing Health Bureau.

Meanwhile, an emergency medical rescue network that covers both urban and rural areas of Beijing has begun to take shape, Liang said.

As well as infectious disease prevention, China has also begun to work comprehensively in various public health fields.

For example, the Organizing Committee of Beijing Olympic Games has already selected farming and breeding bases to provide foods for the Games, said Dai Jianping, deputy director of Department of Medical and Health Services of the organizing committee.

In these bases, strict tests and experiments are being done on livestock and vegetables to ensure athletes and visitors are offered the highest quality food available.