HANGZHOU - The Health Bureau of East China's Zhejiang province on Wednesday reported four new cases of H7N9 bird flu, bringing the total number of confirmed H7N9 cases in the province to 25.

The four cases include a 37-year-old woman surnamed Liao, a 74-year-old man surnamed Niu, a 86-year-old man surnamed Zhao and a 41-year-old man surnamed Zhang.

According to the provincial disease control and prevention center, the four people tested positive for the new strain of avian influenza on Wednesday.

Liao, Niu and Zhao are in critical condition.

Shanghai also confirmed a new case of H7N9 bird flu on Wednesday.

As of Wednesday, China has reported a total of 82 H7N9 cases, including one in Beijing, 31 in Shanghai, two in the central province of Henan, 25 in the eastern province of Zhejiang, 20 in the eastern province of Jiangsu and three in Anhui Province in the east.

So far, sixteen cases have ended in death.