Detection and phylogenetic analysis of contemporary H14N2 Avian influenza A virus in domestic ducks in Southeast Asia (Cambodia)

ABSTRACT

Avian influenza virus (AIV) in Asia is a complex system with numerous subtypes and a highly porous wild birds-poultry interface. Certain AIV subtypes, such as H14, are underrepresented in current surveillance efforts, leaving gaps in our understanding of their ecology and evolution. The detection of rare subtype H14 in domestic ducks in Southeast Asia comprises a geographic region and domestic bird population previously unassociated with this subtype. These H14 viruses have a complex evolutionary history involving gene reassortment events. They share sequence similarity to AIVs endemic in Cambodian ducks, and Eurasian low pathogenicity and high pathogenicity H5Nx AIVs. The detection of these H14 viruses in Southeast Asian domestic poultry further advances our knowledge of the ecology and evolution of this subtype and reinforces the need for continued, longitudinal, active surveillance in domestic and wild birds. Additionally, in vivo and in vitro risk assessment should encompass rare AIV subtypes, as they have the potential to establish in poultry systems.

KEYWORDS:

• H14N2
• surveillance
• avian influenza
• phylogenetics
• Southeast Asia

Acknowledgements

We thank the personnel in the Virology Unit at Institut Pasteur du Cambodge (IPC) who provided technical expertise and analysis and fruitful discussions, including Viseth Srey Horm, Phalla Y, Sonita Kol, Kim Lay Chea, and Veasna Duong; and the support teams at IPC, including the drivers and facilities personnel who made these studies possible. We also thank all local teams, Cambodia Applied Veterinary Epidemiology Training (CAVET) epidemiologists, veterinary officers, and other staff from the National Animal Health and Production Research Institute, General Directorate of Animal Health and Production, Ministry of Agriculture, Forestry, and Fisheries; Ministry of Environment; all staff from the Wildlife Conservation Society; all staff from the Wildlife Conservation Society; and the authors and originating and submitting laboratories of the sequences from the GISAID and GenBank databases (Appendix).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Institute of Allergy and Infectious Diseases [grant number HHSN272201400006C]; National Institutes of Health; Food and Agriculture Organization of the United Nations; Work at Institut Pasteur du Cambodge was supported by the Food and Agriculture Organization of the United Nations and Defense Threat Reduction Agency of the United States [Grant Number STEP TD-O4-001]; US Department of Health and Human Services.