The Centre for Health Protection is investigating a case of influenza A virus (H9N2) involving a nine-month-old girl. H9N2 is a mild form of avian flu.

Centre Controller Dr Thomas Tsang today said the Tseung Kwan O girl developed upper respiratory tract infection symptoms and a fever on March 4. She was admitted to United Christian Hospital on March 6 and discharged three days later.

She has not travelled recently. However, she has gone to a Tseung Kwan O market with her family several times. She is being isolated in Princess Margaret Hospital for observation. Her family members have no symptoms but will have blood tests. The centre and the Food & Environmental Hygiene Department have sent staff to clean and disinfect their home.

Isolated case

Dr Tsang said two girls and a boy were confirmed to have H9N2 in 1999 and 2003 respectively.

"This is an isolated case and the source of infection is being investigated. Based on previous experience, however, we will look especially into bird-to-human transmission. We will look into bird and poultry exposure, visits to places with birds and animals, contact with diseased people or animals," Dr Tsang said.

The Department of Health will inform the World Health Organisation, the Ministry of Health, and health authorities in Macau and Guangdong about the findings. It will issue letters to doctors to alert the medical community. Public hospitals will step up the surveillance of cases with flu-like symptoms. United Christian Hospital will put healthcare workers who have been in close contact with the patient under medical surveillance.

Dr Tsang reminded the public to avoid contact with live poultry to minimise the risk of bird flu infection. For more information click here or call 2833 0111.