BEIJING — A number of provinces in China have stepped up efforts to prevent H7N9 avian flu following reports of scattered human cases of the virus.

Authorities closed 280 live poultry trading and slaughtering venues in Suining city, Southwest China’s Sichuan province, after four human H7N9 cases were reported in the city this year, according to the provincial health authorities.

Commerce officials in Suining have enhanced inspections to crack down on unlicensed poultry businesses.

The central province of Hubei has set up headquarters for the prevention and control of human H7N9 outbreak, according to the provincial Health and Family Planning Commission.

Hubei confirmed 19 human H7N9 cases from Jan 1 to Feb 9, scattered across several cities. Two patients have been discharged from hospital after recovering. The province has dispatched 16 inspection teams to check on prevention efforts.

In Changsha, capital of Central China’s Hunan province, all live poultry markets have been suspended. The province has reported 24 H7N9 cases, including five fatalities, this year.

Eastern China’s Zhejiang province ordered all markets across the province to halt live poultry trading by 6 pm on Feb 11, over bird flu concerns.

Staff with the Zhejiang Center for Disease Control and Prevention said that the province had entered a high season of bird flu outbreak.

In January alone, Zhejiang reported 35 infections of the H7N9 strain of bird flu. Contact with live poultry is the major source of infection, particularly in rural areas.

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.