BEIJING — China’s health authority has called for more efforts to prevent and control the spread of the H7N9 avian flu virus.

The National Health and Family Planning Commission made the call following reports of H7N9 cases in the provinces of Jiangxi and Hunan.

H7N9, a bird flu strain, is most likely to strike in winter and spring. Experts with the Chinese Center for Disease Control and Prevention said that China had entered high season for infection of the H7N9 virus, and the possibility of more reported cases in southern China was not being ruled out.

The center said that the public should avoid contact with dead poultry, live poultry, birds and their waste, and purchase only certified poultry products.