Hong Kong is on public health alert after it confirmed the city's first human case of H7N9 bird flu.

On Tuesday, December 3, the city confirmed that a 36-year old Indonesian woman working as a domestic help has been infected with the deadly virus. The woman is said to have come in direct contact with live poultry.

Authorities reveal that the woman fell sick on November 21 but was hospitalized in a critical condition on November 27 after complaining of cough and shortness of breath. She was later transferred to the intensive care unit at the Queen Mary Hospital in Hong Kong on Friday, November 29.

The patient is said to have a regular travel history to the Chinese city of Shenzhen, which is just around an hour train journey from Hong Kong. Authorities said that the patient visited Shenzhen on November 17, bought a chicken, slaughtered and ate it.

The H7N9 strain was previously isolated to birds only but in early 2013, the first human case of the virus emerged in China. The World Health Organization (WHO) said that there was no evidence of sustained human-to-human transmission of the virus.

As of November 2013, there have been 139 confirmed human cases of H7N9 bird flu reported in mainland China since February this year. The virus has also caused the death of 45 infected patients.

People who have been in close contact with the patient, including the family which employs her, are being tested in isolation. However, the person who had accompanied the patient to the hospital has been tested negative for H7N9.

As a precautionary measure, Hong Kong has suspended import of live poultry from three Shenzhen farms and has also notified the relevant Chinese authorities and the World Health Organization. Authorities said that they will conduct visits to all local chicken farms to ensure that poultry markets are aware of and adhere to the necessary infection control measures. However, the detection of the H7N9 virus will be difficult as infected chicken and ducks do not show any outward symptoms.