Six more H7N9 human cases were reported in south China's Guangdong Province and the neighboring province Jiangxi, Chinese health authorities said on Sunday.
Five men, all in their fifties, were diagnosed with the disease on Friday and Saturday in five different cities in Guangdong. Three are in a critical condition, according to the provincial health and family planning commission.
So far 59 H7N9 human cases have been reported in Guangdong Province. A 74-year-old man from Nanchang City, capital of Jiangxi Province, was diagnosed with the disease on Saturday, the second H7N9 human case in the province.
Human cases of H7N9 have been reported this winter in several other Chinese localities including Shanghai, Fujian, Guizhou and Zhejiang.
H7N9 is a bird flu strain first reported to have infected humans in March 2013. It is most likely to infect humans in winter and spring.