History of Major Epidemics of Avian Influenza in Humans and Public Health Perspectives

DOI: 10.6525/TEB.20160308.32(5).001

Tzu-Jung Tseng1, Hao-Yu Shih2, Ta-Chien Chan3, David Chang-Chun Lee4, Cho-Hua Wan2, Chia-Chi Ku5, Muh-Yong Yen6, Chwan-Chuen King7*

2016 Vol.32 NO.5

Correspondence Author: Chwan-Chuen King7*

  • 1Department of Public Health, College of Medicine,Fu Jen Catholic University , New Taipei , Taiwan
  • 2Department of Veterinary Medicine, School of Veterinary Medicine , National Taiwan University,Taipei, Taiwan
  • 3Research Center for Humanities and Social Sciences,Academia Sinica, Taipei, Taiwan
  • 4Genomic Research Center, Academia Sinica, Taipei,Taiwan
  • 5Institute of Immunology, College of Medicine,National Taiwan University, Taipei, Taiwan
  • 6Taipei City Hospital, Department of Diseases Control and Prevention, Taipei, Taiwan
  • 7Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan


Avian influenza (AI) has had great impacts on global health and socioeconomics in the past two decades. Among many newly emerged influenza viruses, avian influenza viruses (AIVs) have played either indirect or direct role in human infections. The continuous evolvement of AIVs through antigenic drift and genetic reassortment has led to emerging diversities of local virus strains or variants. These dynamic changes of AIVs, even low pathogenic avian influenza (LPAI) viruses, have not only affected poultry health but also resulted in severe and fatal human cases. Moreover, the persistence of these viruses at a population level may lead to outbreaks of AI occurring year after year in a vicious cycle, if they are not completely eradicated.

In light of the emergence of novel H7N9 and other subtypes of AIVs in China in recent years, residents of Taiwan who live closely to this neighboring country must be well prepared in case these viruses are imported. Furthermore, the potential for interspecies transmission to humans from either of the two subtypes of avian H5N2 and H6N1 viruses increases the risk assessment of potential public health threats coming from continuous viral mutations. These two AIV subtypes are relevant in chickens and have been endemic in Taiwan for many years, and the newly emerged novel three subtypes (H5N2, H5N3, and H5N8 clade of AIVs that have spread island-wide since January of 2015 must be expeditiously assessed for publichealth risks.

In summary, this article discusses the history, virology, and epidemiology of avian influenza in humans. We believe that fully understanding virological and epidemiological characteristics of avian influenza viruses and the history of past pandemics or major epidemics will help strengthen the effectiveness of prevention and control measures.

Keywords:Avian influenza, Global epidemiology, Taiwan epidemics, Prevention and control strategies