Guo Huiyu, a leading virologist with the Guangzhou-based Sun Yat-sen University, said the virus found in tests on some of those who have died were similar to those found in animals.

But further scientific tests will have to be conducted to establish the exact source of the virus responsible for the current outbreak of atypical pneumonia, or Severe Acute Respiratory Syndrome (SARS), said Guo.

Alan Schnur, a member of the WHO team, echoed Professor Guo. The director of the Infectious Disease Control Department of the WHO's China Representative Office said his team would be collecting more samples from Guangdong to further their research into the source of the SARS virus.

Questions as to the origin of the outbreak, widely reported as in the south of China, are also being raised.

A Xinhua News Agency report quoted James Maguire from the WHO team as saying that scientists suspect that the source of the SARS virus may originate from a particular type of animal and possibly not from China.

Maguire said he and his colleagues had some primary conjectures on SARS, but had not come to any firm conclusions.

After four days of examination and investigation, the WHO team has found that most of the SARS patients in Guangdong, apart from local medical workers, are employed in the province's restaurant and food industries.

"It is useful and valuable for experts to study the transmission channels of SARS in the coming months," Schnur said.

The WHO team yesterday visited Guangzhou Center for Disease Control and Prevention and had talks with local officials, experts, doctors, nurses and even patients.

They continued to exchange views on the prevention and treatment of SARS with their local counterparts.

The central government has already instructed health departments in Guangdong and Hong Kong to directly exchange data on SARS, including the number of SARS patients, deaths and treatment methods without waiting for specific approval .

Both the WHO and Chinese experts believe that SARS has been basically brought under control in Guangdong, with the number of new cases falling since March.

Guangdong Vice Governor Lei Yulan yesterday reiterated that Guangdong remains safe for investors and tourists.

SARS has affected little on local society, Lei said, with local hospitals, schools, kindergartens, shopping centers and entertainment venues all operating as usual.

And the coming 93rd Chinese Export Commodities Fair, the country's biggest trade event, will get under way as scheduled on April 15 in Guangzhou.

The WHO team which consists of experts from the United States, Britain and Germany will continue to visit more hospitals and patients in the coming days to collect more detailed and valuable materials and samples aimed at finding an effective way of treating SARS.

The WHO team is expected to leave Guangzhou tomorrow.

(China Daily April 7, 2003)