Health specialists want the surveillance in place in case SARS, which ebbed in June after its worldwide outbreak, makes a return in coming months.
In testing the system now, the WHO hopes to see China detecting more suspected SARS cases — even if those don't prove to be the disease — under the belief that many false alarms, as opposed to few or none, show better medical vigilance.
WHO officials in Beijing have said they were concerned that China, unlike other affected countries, has had very few false alarms.
The new surveillance system will require medical workers to be more specific in questioning people with SARS-like symptoms and will push for better handling of information.
The trial will involve between 10 and 14 hospitals in Guangdong, Shanxi and Beijing — areas hit hardest by the recent outbreak, said WHO spokeswoman Maria Cheng.
"We need to have this in place just to be absolutely sure that if SARS comes back in the winter, as some people suspect it will, we will be ready," said Cheng, who is based in Beijing.
Severe acute respiratory syndrome emerged from China's southern province of Guangdong in November and killed 349 people in the country, more than half of them in the capital, Beijing. Another 5,300 people were infected before the flu-like illness ebbed in June. Worldwide, it killed more than 900 people.
Researchers have warned that SARS could re-emerge when cold weather returns. Scares involving SARS-like cases have already been reported in Canada and Hong Kong, the two hardest-hit sites outside of mainland China.
"We'd rather have false reporting and rumors than not hear anything at all. It's always better to over-report than underreport," Cheng said.
In the early days of the outbreak, China was criticized for reluctance to release information on its SARS infections. The government later vowed to be more open, and launched an aggressive campaign to fight the disease.
The state-controlled Star Daily newspaper reported Wednesday that China's Health Ministry announced it would begin testing patients in a bid to track the virus suspected of causing SARS.
The new WHO system, crafted with the help of Chinese health officials, will be tested for four weeks, Cheng said. It will undergo a weeklong review in Beijing before recommendations are presented to the national Ministry of Health.
WHO hopes the system will be in place around the country by the end of October, she said.
Officials from WHO have also suggested that the Chinese government appoint someone to investigate SARS rumors, Cheng said.