Bird Garden in Mong Kok was yesterday closed for three weeks and more than 1,000 birds were slaughtered after traces of potentially deadly bird flu were found in a shop.
The H5N1 virus was detected in a swab sample collected last month from a bird cage holding an Oriental magpie robin, raising fears the disease could be passed to pet buyers.
But the Health Department said yesterday the risk of transmission to humans 'is not particularly high' as the swab trace was probably from a wild bird that flew into the shop.
All birds caged in the affected stall turned out to be healthy but were slaughtered as a precaution, Dr Thomas Sit Hon-chung, assistant director for inspection and quarantine for the Agriculture, Fisheries and Conservation Department, said.
'The exact source of the infection is still unknown to us, but we suspect it is more likely to belong to some wild birds. Risk of human infection is still low,' Sit said.
'We believe it is also necessary to close down the garden to undertake a thorough cleansing. It will not reopen until all samples we have taken are free of the virus.'
An infectious diseases expert suggested the swab was more likely to have come from the pet bird, as it was unlikely a wild bird would get into a cage. But University of Hong Kong microbiologist Ho Pak-leung added there was little risk to human health.