A staff member of Shanghai Epidemic-Prevention Centre collects the blood sample of a worker at the site where suspected cases of birdflu were found in Nanhui District of Shanghai Jan. 31, 2004. Since the suspected case of bird flu was spotted, Shanghai municipal governments has enforced sweeping poultry culling and prompted quarantine measures. All the 35,000 poultry at the site and other 300,000 poultry within a three kilometer radius of the site have been slaughtered. No infection to human beings has been found in the city. (Xinhua Photo)

Staff members of Shanghai Epidemic-Prevention Centre register the information of workers at the site where suspected cases of birdflu have been found in Nanhui District of Shanghai Jan. 31, 2004. (Xinhua Photo)