BEIJING, Dec. 20 (Xinhua) -- China's top health authority on Friday told health departments at all levels to tighten supervision of new pneumonia and flu cases.

According to the National Health and Family Planning Commission, on Wednesday, east China's Jiangxi Province confirmed a human case of H10N8, a new strain of bird flu.

The commission also said that south China's Guangdong Province has reported six cases of H7N9 bird flu since October, and east China's Zhejiang Province reported five cases in the second half of this year.

The commission urged local health authorities to make prevention and control of H7N9 a priority, strengthen monitoring of the virus, and step up medical treatment.

Winter and spring are traditionally the worst seasons for infectious respiratory disease.