HONG KONG (AFP) - A seven-year-old Hong Kong girl is being tested for the H7N9 flu virus after she returned from Shanghai and showed flu-like symptoms, officials said on Friday in the city's first suspected case.

Health officials said the result of the test was expected later on Friday, coming after the virus killed six in China and prompted the closure of all live poultry markets in Shanghai as well as the culling of over 20,000 birds.

"She has travelled to Shanghai in late March and had contact with poultry.

We have quarantined her," the Hospital Authority's chief infection control officer Dominic Tsang said.

He would not give details of the girl's condition other than that she was displaying flu-like symptoms, including fever.

Health Minister Ko Wing-man said the city would step up random testing in local poultry and mobilise additional staff to carry out body temperature checks on inbound travellers at the border.

He said suspension of poultry from mainland China was not necessary at the moment.

Hong Kong was the site of the world's first major outbreak of bird flu among humans in 1997, when six people died from a mutated form of the virus, which is normally confined to poultry. Millions of birds were then culled.

Experts are concerned that the H7N9 virus appears to have spread across a wide geographical area, with people sickened not only in Shanghai, but also the nearby provinces of Zhejiang, Jiangsu and Anhui.