CHANGSHA -- Four more human cases of H7N9 avian flu were reported in Central China's Hunan province, according to the provincial health authorities on Thursday.

Hunan has reported 24 H7N9 cases so far this year.

A male patient, identified only by his surname Wan, was diagnosed in Yueyang city. He is currently in the intensive care unit of a hospital in the capital city, Changsha.

Another three people have also been hospitalized but their condition has been described as "stable" by the health authority.

The sale of live poultry has been suspended across all markets in Changsha, the city government said Thursday.

On Tuesday, the provincial center for disease control and prevention temporarily closed some markets that sold live poultry in Changsha and Yueyang cities.

The markets were ordered to disinfect on a regular basis to prevent the virus from spreading.

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