Hong Kong health authorities said Saturday there was no sign of bird flu spreading among humans after the densely-populated city recorded its first case of the virus in seven years.
"So far we feel that the risk of avian influenza in Hong Kong is still slim, and also there is no indication of human to human transmission," Secretary for Food and Health York Chow told reporters.
The city on Thursday recorded its first human case of the potentially fatal illness since 2003 and raised its avian influenza alert level to "serious".
The 59-year-old woman who tested positive for Influenza A (H5), a variant of bird flu, after returning from a trip to mainland China, was in a serious but stable condition in hospital, he added.
Tests conducted at 30 chicken farms in the territory had proved negative, he said.
Hong Kong recorded its last human case of bird flu in 2003, and was the site of the world's first major outbreak among humans in 1997, when six people died of a mutation of the virus, which is normally confined to poultry.
Millions of poultry were culled in the 1997 outbreak, which was followed six years later by a full-blown panic when the deadly respiratory disease SARS emerged in 2003, killing about 300 people.
Public anxiety returned to the city of seven million people last year with an outbreak of swine flu that has so far claimed about 80 lives.
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