Shenzhen City in south China's Guangdong Province on Monday reported a new human infection of H7N9 bird flu.

A girl aged six has tested positive for H7N9 and is hospitalized, the Guangdong Health and Family Planning Commission said in a statement. Her case is described as "mild".

Shenzhen reported its first H7N9 human case this winter on Dec. 30. Both victims are residents of the city's Longhua New District which has now closed its live poultry markets. Most bird flu cases in humans come from exposure to infected poultry.

Authorities in Guangdong and Hong Kong last week culled thousands of chickens after exports to Hong Kong were found to be infected with the virus.

Hong Kong raised its response level in hospitals to "serious" from "alert", after a 68-year-old woman was hospitalized on Dec. 25 with H7N9, the region's first case since early 2014. The woman had arrived from Shenzhen two weeks before.