The World Health Organization (WHO) will have four teams working with China on the investigation into the recent SARS cases on the Chinese mainland, WHO spokesman Bob Dietz said Beijing on Tuesday.

"In addition to the bio-safety team investigating the laboratories, we also have a team to help with the epidemiological investigations, one to help make sure infection control in hospitals, and a team that will visit Anhui," Dietz told Xinhua.

The spokesman said WHO experts will arrive in China in two or three days.

Meanwhile, sources with the Chinese Health Ministry said the WHO experts are on their way to China. "After they arrive, the ministry will meet with them and discuss the details for cooperation. We hope the joint investigation could start soon," an official with the ministry said.

Since April 22, China has reported two confirmed and six suspected SARS cases in Anhui and Beijing. Early warning systems on SARS have been enacted in the two places and local health authorities nationwide have tightened surveillance and report efforts on SARS.

Experts blamed the SARS occurrences on possible laboratory infection. Currently, the Institute of Virology under China's Center for Disease Prevention and Control, where the Anhui SARS patient and a Beijing suspected patient used to work, has been sealed and isolated. No staff of the institute who are now in quarantine have shown abnormal symptoms.

In addition, the ministry has asked hospitals above the county level to recheck the death and pneumonia cases with no clear causes which have occurred since March 20. No cases have been found related with SARS so far, the ministry said.

Source: Xinhua