A 31-year-old woman from Dongguan in the Guangdong Province of China was recently diagnosed with avian influenza A(H7N9), Hong Kong's Centre for Health Protection of the Department of Health (DH) announced on Friday.
The patient is currently in critical condition at a Guangzhou hospital.
"Locally, we will remain vigilant and work closely with the World Health Organization and relevant health authorities to monitor the latest developments," a DH spokesman said.
As of Monday, 444 human patients had been diagnosed with avian influenza on the Chinese mainland. People who come into regular contact with birds and bird droppings are especially susceptible.
Authorities have tightened control points between regions to prevent spreading of the disease. The DH also has implemented thermal imaging systems to test the body temperatures of travelers.
Health professionals have been using broadcasts and posters to educate visitors and locals about the disease.
Anyone experiencing symptoms of avian influenza, including a fever or respiratory symptoms, should don a mask and seek immediate medical attention.
Chinese officials are reassuring the public that maintaining personal hygiene, including washing hands, and having minimal contact with birds is the best way to avoid contacting avian influenza.
"In view of cases confirmed on the mainland, members of the public should maintain good personal, food and environmental hygiene at all times during travel,” the DH spokesman said.