40pc of bird flu victims haven't touched poultry

A top mainland scientist said 40 per cent of the people who have tested positive for the new, deadly strain of bird flu had no recent contact with poultry, and so it is still unclear how they contracted the virus.

The remark by Dr Zeng Guang , chief of epidemiology at the Chinese Centre for Disease Control and Prevention, came as Shanghai and Zhejiang authorities announced five new cases of H7N9, bringing the number of confirmed cases to 82, with 17 of them fatal.

"How were they infected? It is still a mystery," he was quoted by The Beijing News yesterday as saying. All the cases so far have been in China.

The Ministry of Health cited Feng Zijian, director of the CDC's office of emergency response, as saying the source of the illness was hard to pinpoint. He noted that during the last major bird flu outbreak, which involved H5N1, half of the victims could not remember whether they had come in contact with poultry or other birds. Still, he said he believed that all infected during this outbreak must have come in contact with an environment contaminated by fowl, or in contact with birds directly.

Of the five new cases, just one was in Shanghai - an 89-year-old man from Jiangsu province. Authorities did not give his condition. The first person infected in Beijing, a seven-year-old girl, left hospital yesterday.

A four-year-old boy in the capital infected with the strain but not displaying symptoms remained in quarantine.

Health authorities hope the boy will help doctors understand the virus. He was identified as a carrier via a random blood test of people in or near the poultry industry.