Proposal for a Global Classification and Nomenclature System for A/H9 Influenza Viruses
Abstract
Influenza A/H9 viruses circulate worldwide in wild and domestic avian species, continuing to evolve and posing a zoonotic risk. A substantial increase in human infections with A/H9N2 subtype avian influenza viruses (AIVs) and the emergence of novel reassortants carrying A/H9N2-origin internal genes has occurred in recent years. Different names have been used to describe the circulating and emerging A/H9 lineages. To address this issue, an international group of experts from animal and public health laboratories, endorsed by the WOAH/FAO Network of Expertise on Animal Influenza, has created a practical lineage classification and nomenclature system based on the analysis of 10,638 hemagglutinin sequences from A/H9 AIVs sampled worldwide. This system incorporates phylogenetic relationships and epidemiologic characteristics designed to trace emerging and circulating lineages and clades. To aid in lineage and clade assignment, an online tool has been created. This proposed classification enables rapid comprehension of the global spread and evolution of A/H9 AIVs.
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BibTeX
@article{fusaro2026proposal,
title = {{Proposal for a Global Classification and Nomenclature System for A/H9 Influenza Viruses}},
author = {Alice Fusaro and Juan Pu and Yong Zhou and Lu Lu and Luca Tassoni and Yu Lan and Tommy Tsan-Yuk Lam and Zoe Song and Justin Bahl and Jiani Chen and George F Gao and Isabella Monne and Jinhua Liu and International H Evolution Consortium},
journal = {Emerging Infectious Diseases},
year = {2026},
month = aug,
doi = {10.3201/eid3008.231176},
url = {https://pasteur.hal.science/pasteur-05733404v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Proposal for a Global Classification and Nomenclature System for A/H9 Influenza Viruses
AU - Alice Fusaro
AU - Juan Pu
AU - Yong Zhou
AU - Lu Lu
AU - Luca Tassoni
AU - Yu Lan
AU - Tommy Tsan-Yuk Lam
AU - Zoe Song
AU - Justin Bahl
AU - Jiani Chen
AU - George F Gao
AU - Isabella Monne
AU - Jinhua Liu
AU - International H Evolution Consortium
PY - 2026
DA - 2026/08/31
JO - Emerging Infectious Diseases
DO - 10.3201/eid3008.231176
UR - https://pasteur.hal.science/pasteur-05733404v1
AB - Influenza A/H9 viruses circulate worldwide in wild and domestic avian species, continuing to evolve and posing a zoonotic risk. A substantial increase in human infections with A/H9N2 subtype avian influenza viruses (AIVs) and the emergence of novel reassortants carrying A/H9N2-origin internal genes has occurred in recent years. Different names have been used to describe the circulating and emerging A/H9 lineages. To address this issue, an international group of experts from animal and public health laboratories, endorsed by the WOAH/FAO Network of Expertise on Animal Influenza, has created a practical lineage classification and nomenclature system based on the analysis of 10,638 hemagglutinin sequences from A/H9 AIVs sampled worldwide. This system incorporates phylogenetic relationships and epidemiologic characteristics designed to trace emerging and circulating lineages and clades. To aid in lineage and clade assignment, an online tool has been created. This proposed classification enables rapid comprehension of the global spread and evolution of A/H9 AIVs.
SN - 1080-6040
SN - 1080-6059
ER -