A Guangdong health official yesterday admitted authorities could not rule out the possibility of more human bird flu cases in the province because the sources of infection in previous patients had not been determined. Huang Fei, deputy director of the Guangdong Health Department, said a Shenzhen man with the H5N1 virus was still in a critical condition and health experts could not explain how he, or a Guangzhou man who died of the disease, contracted it in the absence of a bird flu outbreak in poultry in the province. 'We do not rule out the possibility that more human bird flu cases will occur,' Mr Huang said. He made the remarks at the end of a two-day meeting in Dongguan on infectious diseases attended by Hong Kong, Guangdong and Macau health officials. During the meeting, the three parties approved the creation of a joint team of health experts to co-ordinate prevention and emergency responses to human bird flu outbreaks in the region. The team - the Guangdong-Hong Kong-Macau Experts Team on the Prevention and Cure of Human Bird Flu - comprises 20 clinical, epidemiological and laboratory testing specialists, of whom six are from Hong Kong and eight from Guangdong. The Hong Kong members are Tsang Ho-fai, Chuang Shuk-kwan and Wilina Lim Wei-ling from the Centre for Health Protection, Lai Sik-to and Chow Chun-bong from Princess Margaret Hospital, and Chu Cong-ming from the United Christian Hospital. Hong Kong health director Lam Ping-yan said the team would meet regularly and would improve bird flu prevention and control efforts in the region. Mr Huang said the creation of the expert team could facilitate further co-operation in the handling of a human bird flu outbreak and speed up the authorities' response to one. 'In the past, health experts were sent to the scene where the disease broke out after health officials from the three sides got in contact, but the experts will meet regularly themselves in future,' he said. The three parties also signed an agreement to co-ordinate emergency responses to other major public health crises in the region, focusing on infectious diseases and those with unknown causes.