Hong Kong Confirms First Deadly Case of Winter

A woman is critically ill in Hong Kong with the lethal H7N9 strain of bird flu, the first confirmed case in the city this winter, Hong Kong government officials said. The city's influenza pandemic response level was elevated to "serious."

The woman, 68, was admitted to a hospital on Thursday after falling ill on Dec. 19, the Hong Kong government said in a statement issued Saturday. The case has been classified as "imported" because the woman had recently been in the Longgang district of Shenzhen in mainland China, where the first human case of the deadly H7N9 strain was reported in March 2013. The woman ate chicken while in Shenzhen but was not exposed to live poultry, the government said.

The government is trying to track down friends of the woman who may have been exposed to the virus, the source of which had not been determined.

The first known human case of the H7N9 strain was reported in mainland China in March last year, according to the World Health Organization. The virus subsequently spread to Hong Kong last December where it killed three people.