CHANGSHA -- A resident of Central China's Hunan province died of H7N9 flu infection, said provincial authorities on Tuesday.

The 48-year-old waste trader surnamed Mo in Jishou city developed symptoms on Wednesday and died Sunday in the hospital despite doctors' efforts, said the Hunan Provincial Center for Disease Control and Prevention.

Mo tested positive for the H7N9 virus, said the center. The patient suffered high blood pressure.

The center said human infections of the flu virus may occur in the summer.

H7N9 is a bird flu strain first reported to have infected humans in China in March 2013. Infections are most likely to occur in winter and spring.