From H5N1 to HxNy: An epidemiologic overview of human infections with avian influenza in the Western Pacific Region, 2003-2017

An epidemiological overview of human infections with HxNy avian influenza in the Western Pacific Region, 2003-2022

Avian influenza subtype A(HxNy) viruses are zoonotic and may occasionally infect humans through direct or indirect contact, resulting in mild to severe illness and death. Member States in the Western Pacific Region (WPR) communicate and notify the World Health Organization of any human cases of A(HxNy) through the International Health Regulations (IHR 2005) mechanism. This report includes all notifications in the WPR with illness onset dates from 1 November 2003 to 31 July 2022. During this period, there were 1972 human infections with nine different A(HxNy) subtypes notified in the WPR. Since the last report, an additional 134 human avian influenza infections were notified from 1 October 2017 to 31 July 2022. In recent years there has been a change in the primary subtypes and frequency of reports of human A(HxNy) in the region, with a reduction of A(H7N9) and A(H5N1), and conversely an increase of A(H5N6) and A(H9N2). Furthermore, three new subtypes A(H7N4), A(H10N3) and A(H3N8) notified from the People's Republic of China were the first ever recorded globally. The public health risk from known A(HxNy) viruses remains low as there is no evidence of person-to-person transmission. However, the observed changes in A(HxNy) trends reinforce the need for effective and rapid identification to mitigate the threat of a pandemic from avian influenza if person-to-person transmission were to occur.

Marking the 1918 influenza pandemic centennial: addressing regional influenza threats through the Asia Pacific Strategy for Emerging Diseases and Public Health Emergencies

The Western Pacific Region (WPR) is home to nearly 1.9 billion people. Over the past decades, the Region has experienced a number of significant emerging infectious disease events, including human infections with avian influenza viruses. Health security threats continue and become even more complex in this highly interconnected world. With humans and animals living in close proximity, the Western Pacific region provides an ideal environment for influenza viruses to pass from animals to humans, potentially mutate and spread globally in a rapid manner. In efforts to prevent or mitigate the next pandemic, WPR has been working together to ensure a strong regional human-animal-environmental influenza surveillance system is in place for rapid detection, identification, reporting and response to any events with pandemic potential.