The Hong Kong Centre for Health Protection (CHP) of the Department of Health (DH) yesterday (May 17) received notification of one additional human case of avian influenza A(H7N9) from the Health and Family Planning Commission of Guangdong Province. The patient is a 37-year-old man who lives in Zhongshan. He is currently hospitalised for treatment.
A total of 426 human cases of avian influenza A(H7N9) have been confirmed in the Mainland, including Zhejiang (138 cases), Guangdong (108 cases), Jiangsu (54 cases), Shanghai (41 cases), Hunan (23 cases), Fujian (22 cases), Anhui (14 cases), Jiangxi (eight cases), Beijing (four cases), Henan (four cases), Guangxi (three cases), Shandong (three cases), Jilin (two cases), Guizhou (one case, imported from Zhejiang) and Hebei (one case).
According to the CHP, avian influenza is caused by those influenza viruses that mainly affect birds and poultry, such as chickens or ducks. Since the virus does not commonly infect humans, there is little or no immune protection against it in the human population. However, if an avian influenza virus acquired the capacity to spread easily from person to person, either through adaptation or acquisition of certain genes from human viruses, an influenza pandemic can occur. Human cases infected with avian influenza A (H5N1, H7N9 and H9N2) viruses have been identified in Hong Kong, Mainland China and other parts of the world, while human infections due to H10N8 and H6N1 viruses have been first reported in Mainland China and Taiwan respectively since 2013.
Clinical presentation of avian influenza in humans includes eye infection (conjunctivitis), flu-like symptoms (e.g. fever, cough, sore throat, muscle aches) or severe respiratory illness (e.g. chest infection). The more virulent forms [e.g. infection by avian influenza A (H5N1, H7N9 or H10N8) viruses] can result in respiratory failure, multi-organ failure and even death.
People mainly become infected with avian influenza through close contact with infected birds and poultry (live or dead) or their droppings. Human-to-human transmission is inefficient. For more infectious disease news and information, visit and “like” the Infectious Disease News Facebook page.