CHP investigating a case of influenza A (H9) infection
The Centre for Health Protection (CHP) of the Department of Health (DH) is today (February 7) investigating an imported case of influenza A (H9) infection affecting a boy aged 7.
The patient has underlying illnesses, who has developed cough and runny nose since February 4 and fever on the next day. On February 5, he was brought to Wang Tau Hom Jockey Club General Out-patient Clinic (GOPC) for medical advice, and was transferred to Kwong Wah Hospital (KWH) where he was admitted to the isolation ward for further management. He was transferred to general ward of KWH yesterday (February 6) and was transferred to isolation ward of Princess Margaret Hospital for treatment today. He has been in stable condition.
His nasopharyngeal swab tested positive for the influenza A (H9) virus upon testing. Subtyping result is pending. His clinical diagnosis was avian influenza.
Preliminary investigation of the CHP revealed that the patient visited his maternal grandparents' home in Shenzhen during the incubation period, where backyard poultry was kept. However, the patient had no direct poultry contact recently, nor consumption of undercooked poultry, or contact with patients. His home contacts have remained asymptomatic so far.
"Investigations are ongoing. Healthcare workers of Wang Tau Hom Jockey Club GOPC, KWH and the ambulance service, as well as related patients in KWH, have been put under medical surveillance," a spokesman for the DH said.
"There are various types of influenza viruses. Apart from those which can circulate among humans and cause seasonal influenza, many other influenza A viruses are found in birds and other animal species. Some of these animal viruses may occasionally infect humans, avian influenza viruses are one example. Avian influenza is caused by those influenza viruses that mainly affect birds and poultry, such as chickens or ducks. Human cases infected with avian influenza A viruses have been identified in recent years," the spokesman explained.
Novel influenza A infection, including influenza A(H9), is a notifiable infectious disease in Hong Kong. Eight cases of influenza A (H9N2) had been reported in the past, including two local cases in 1999, one local case each in 2003 and 2007, an imported case in 2008, an imported case and one with the source of infection unclassified in 2009, and one imported case in 2013. No deaths have been recorded so far. Influenza A (H9N2) infection is a mild form of avian influenza.
The CHP will inform the health authority of Guangdong of the case.
"The CHP's surveillance with public and private hospitals, with practising doctors and at boundary control points is firmly in place. Suspected cases will be immediately referred to public hospitals for follow-up investigation," the spokesman added.
"Travellers, especially those returning from avian influenza-affected areas and provinces with fever or respiratory symptoms, should immediately wear masks, seek medical attention and reveal their travel history to doctors. Healthcare professionals should pay special attention to patients who might have had contact with poultry, birds or their droppings in affected areas and provinces," the spokesman advised.
Members of the public should remain vigilant and take heed of the preventive advice against avian influenza below:
* Do not visit live poultry markets. Avoid contact with poultry, birds and their droppings. If contact has been made, thoroughly wash hands with soap;
* Poultry and eggs should be thoroughly cooked before eating;
* Wash hands frequently with soap, especially before touching the mouth, nose or eyes, handling food or eating; after going to the toilet or touching public installations or equipment (including escalator handrails, elevator control panels and door knobs); or when hands are dirtied by respiratory secretions after coughing or sneezing;
* Cover the nose and mouth while sneezing or coughing, hold the spit with a tissue and put it into a covered dustbin;
* Avoid crowded places and contact with fever patients;
* Wear masks when respiratory symptoms develop or when taking care of fever patients;
* Travellers if feeling unwell when outside Hong Kong, especially if having a fever or cough, should wear a surgical mask and inform the hotel staff or tour leader and seek medical advice at once; and
* Travellers returning from affected areas with avian influenza outbreaks should consult doctors promptly if they have flu-like symptoms, and inform the doctor of the travel history and wear a surgical mask to help prevent spread of the disease.
The public may visit the CHP's avian influenza page (www.chp.gov.hk/en/view_content/24244.html) and website (www.chp.gov.hk/files/pdf/global_statistics_avian_influenza_e.pdf) for more information on avian influenza-affected areas and provinces.