Genetic characterization of LPAI-H4N2 and H4N8 viruses recovered from free-grazing ducks in Thailand

Authors

Supanat Boonyapisitsopa, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Supassama Chaiyawong, Emerging and Re-emerging Infectious Diseases in Animals, Center of Excellence, and One Health Research Cluster, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Kamonpan Charoenkul, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Kitikhun Udom, Emerging and Re-emerging Infectious Diseases in Animals, Center of Excellence, and One Health Research Cluster, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Ekkapat Chamsai, Emerging and Re-emerging Infectious Diseases in Animals, Center of Excellence, and One Health Research Cluster, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Napawan Bunpapong, Veterinary Diagnostic Laboratory, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Somsak Pakpinyo, Emerging and Re-emerging Infectious Diseases in Animals, Center of Excellence, and One Health Research Cluster, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, ThailandFollow
Alongkorn Amonsin Prof. Dr., Department of Veterinary Public Health, Faculty of Veterinary Sciences, Chulalongkorn University, Bangkok, Thailand.Follow

Abstract

nfluenza A viruses (IAVs) can infect birds and various mammals. In this study, we retrospectively isolated and characterized IAVs (n=8) from oropharyngeal and cloacal swab samples of free-grazing ducks collected during December 2018 to December 2021, by using egg inoculation and whole-genome sequencing. The IAVs could be subtyped as IAV-H4N2 (n = 3) and IAV-H4N8 (n = 5) using real-time RT-PCR assays. Genetic and phylogenetic analyses revealed that all eight genes of Thai IAV-H4 belong to the Avian Eurasian lineage. Both Thai IAV-H4N2 and IAV-H4N8 exhibited low pathogenic avian influenza (LPAI) characteristics and were susceptible to oseltamivir and amantadine. This study did not detect any reassortant viruses among IAV-H4N2 and IAV-H4N8. Overall, our findings suggest that IAV-H4N2 and IAV-H4N8 are endemic and circulating among free-grazing ducks in Thailand. Therefore, routine surveillance of IAVs in free-grazing ducks is necessary to monitor the emergence of new reassortant and potential virulent viruses.

DOI

10.56808/2985-1130.3866

First Page

1

Last Page

22

Recommended Citation

Boonyapisitsopa, Supanat; Chaiyawong, Supassama; Charoenkul, Kamonpan; Udom, Kitikhun; Chamsai, Ekkapat; Bunpapong, Napawan; Pakpinyo, Somsak; and Amonsin, Alongkorn Prof. Dr. (2025) "Genetic characterization of LPAI-H4N2 and H4N8 viruses recovered from free-grazing ducks in Thailand," The Thai Journal of Veterinary Medicine: Vol. 55: Iss. 2, Article 13.
DOI: https://doi.org/10.56808/2985-1130.3866
Available at: https://digital.car.chula.ac.th/tjvm/vol55/iss2/13