GUANGZHOU, Jan. 13 -- South China's Guangdong Province reported another two H7N9 human infections, local authorities said Tuesday.

Both cases were found in Shenzhen City. A 57-year-old woman and a 41-year-old man were both confirmed as infected on Monday, the provincial health and family planning commission said in a statement.

The woman is in a critical condition at a local hospital, while the man is stable.

The health authorities warned that the province has entered a high-incidence period for bird flu, which occurs in winter and spring, and that risks for occasional human infections are high.

In addition to Guangdong, Shanghai Municipality, Fujian Province and Zhejiang Province have all reported human cases of H7N9 this winter.