Dead migratory birds infected with the H5N1 flu virus have turned up at Chek Lap Kok and Lok Ma Chau, the government revealed yesterday. The detection makes it more likely that these birds may have spread the flu, which has twice shown a capacity to infect humans. A Tsing Yi father and son who travelled to Fujian became the first people to be infected by bird flu since 1997, when six people died from the strain. The man died last Monday despite treatment at Princess Margaret Hospital while his son was treated and discharged. His eight-year-old daughter died of suspected pneumonia on February 4 on the mainland. Hong Kong has now begun discussions with Beijing health authorities to start a vaccination programme for chickens exported to Hong Kong to minimise the risk of bird flu, legislators were told yesterday. The human cases follow sporadic outbreaks of H5N1 flu since December, when ducks and geese died at Penfold Park, at Sha Tin racecourse. Since then, birds in Kowloon Park, six wet markets and five farms have been infected by H5N1 flu. Liu Kwei-kin, the Deputy Director of Agriculture, Fisheries and Conservation, yesterday told a joint meeting of the Legislative Council panels on health services and food and environmental hygiene: 'Apart from Penfold Park and Kowloon Park we have also found two wild birds with the virus in Lok Ma Chau and at Chek Lap Kok.' He said monitoring of live birds at Mai Po Nature Reserve had not detected signs of H5N1 among migratory birds there. The Secretary for Health, Welfare and Food, Yeoh Eng-kiong, said vaccination of mainland chickens was being discussed with mainland officials after a decision to vaccinate all local farm chickens against the bird flu. He said a 'mutated virus' could have affected the boy and his father. He also said the Beijing authorities had 'acted very fast' in handling the incident. But in the case of the dead daughter, he said: 'We need to look at the reporting system and discuss how it can be enhanced. 'Perhaps nobody knew it was a communicable disease at all. We do not know the cause of death.' Dr Lo Wing-lok, the legislator for the medical sector, said it would be difficult to tell how the girl died. 'She was cremated and there was no evidence that can be traced from this particular girl. So it is a matter of what we can learn from this case so that if a similar case occurs we will be able to collect more information from the deceased.' Michael Mak Kwok-fung, who represents the health services sector in Legco, called on the mainland authorities to test pneumonia patients there for bird flu. He said there could be a link between atypical pneumonia and the H5N1 virus. DEADLY OUTBREAKS Dead ducks and geese with the H5N1 virus were found in Sha Tin in December Six wet markets and five farms have been infected The virus has also been found in wild birds in Lok Ma Chau and at Chek Lap Kok