Mainland poultry imports will be tested for H7N9 bird flu using the more effective "serology" test starting tomorrow, the food and health chief said.
Serological testing involves studying blood serum for antibodies.
But Ko Wing-man did not say whether imports will be halted if any poultry tests positive for the virus, which has so far infected 211 people in the mainland and three in Hong Kong.
Ko said 30 samples from each batch of mainland poultry will be tested and if any tests positive for H7N9, the sample size will be increased by an additional 120 and DNA tests carried out.
Ko also voiced concern about the H7N9 outbreak in the mainland, where more than 40 cases have already been reported this year.
He said serological testing in Man Kam To Animal Inspection Station and local poultry farms will be able to "better enhance the safety of imported poultry, as well as protect Hong Kong people against the threat of H7N9."
Ko added: "The serum test can detect antibodies to the virus in poultry, giving people an idea of how widely it is spreading among the bird population, and can trace a longer history of infection." The DNA test will be carried out for accuracy as the serology test cannot determine whether the birds have recovered and developed immunity or could still spread the virus.
The DNA test has been in use since April, also on 30 samples in each batch of mainland and local farmed chicken.
Ko noted that experts say there has only been limited human-to-human transmission so far of H7N9.
Recent cases in Shanghai involved two members of the same family and a doctor. "In the first case, it's possible they had been exposed to a poultry market. We cannot yet confirm human-to- human infection in this case," Ko said.
"For the doctor's case, we need to further study whether during the incubation period the doctor was in contact with any H7N9 cases, or was exposed to a poultry market environment."
Ko said pressure on public hospitals will increase if more new H7N9 cases are reported in Hong Kong.
Meanwhile, the Centre for Health Protection late on Monday received notification of seven more H7N9 cases in the mainland, with three each in Shenzhen and Zhejiang province, and another in Jiangsu province.
The Shenzhen cases are a 76-year- old man and two women, aged 39 and 59, while the patients in Zhejiang are all men, aged 49, 57 and 70. The case in Jiangsu involves a man aged 71.
All seven are in hospital and their condition was not disclosed.