Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry industry and public health

Abstract

The H9N2 and H5N1 avian influenza viruses (AIVs) have been circulating in poultry in China and become endemic since 1998 and 2004, respectively. Currently, they are prevalent in poultry throughout China. This endemicity makes them actively involved in the emergence of the novel lineages of other subtypes of influenza viruses, such as the well-known viruses of the highly pathogenic avian influenza (HPAI) H5N2 and the 2013 novel H7N7, H7N9 and H10N8 subtypes, thereby threatening both the poultry industry and public health. Here, we will review briefly the prevalence and evolution, pathogenicity, transmission, and disease control of these two subtypes and also discuss the possibility of emergence of potentially virulent and highly transmissible AIVs to humans.

Keywords

avian influenza virus / H9N2 / H5N1 / novel viruses / public health

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (31502076), the Jiangsu Provincial Natural Science Foundation of China (BK20150444), the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province, China (15KJB230006), the Postdoctoral Science Foundation of Jiangsu Province, China (1501015B), the earmarked fund for Modern Agro-industry Technology Research System (nycytx-41-G07), and a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

Jiao Hu and Xiufan Liu declare that they have no conflict of interest or financial conflicts to disclose.

This article is a review and does not contain any studies with human or animal subjects performed by any of the authors.

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