Expanding Horizons: Host Range Evolution and Treatment Strategies for Highly Pathogenic Avian Influenza H5N1 and H7N9
Open Access
Abstract
Avian influenza viruses (AIVs), including H5N1 and H7N9, from the Orthomyxoviridae family present substantial public health concerns. The predominant circulating clade 2.3.4.4b has demonstrated enhanced capacity for mammalian adaptation, raising concerns about potential reassortment with human seasonal influenza viruses. Unlike H7N9’s limited host range, H5N1 infects birds, various mammals, and humans. Recent concerns include widespread H5N1 infection of U.S. dairy cattle across 18 states, affecting over 1000 herds with 71 human infections (70 H5N1 and 1 H5N5). Key observations include cow-to-cow transmission, viral presence in milk, and transmission to humans, mainly through occupational exposure. Evidence of mammal-to-mammal transmission has been documented in European and Canadian foxes and South American marine mammals. Standard pasteurization effectively inactivates the virus in milk. The continuing mammalian adaptations, particularly mutations like PB2-E627K, PB2-D701N, and PB2-M535I, suggest potential for further evolution in new hosts, emphasizing the need for enhanced surveillance to mitigate pandemic risks.Keywords
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This publication has 55 references indexed in Scilit:
- sa-mRNA influenza vaccine raises a higher and more durable immune response than mRNA vaccine in preclinical modelsVaccine, 2025
- Structure of a zoonotic H5N1 hemagglutinin reveals a receptor-binding site occupied by an auto-glycanStructure, 2025
- Receptor binding, structure, and tissue tropism of cattle-infecting H5N1 avian influenza virus hemagglutininCell, 2025
- Pacific and Atlantic sea lion mortality caused by highly pathogenic Avian Influenza A(H5N1) in South AmericaTravel Medicine and Infectious Disease, 2024
- A comprehensive review of highly pathogenic avian influenza (HPAI) H5N1: An imminent threat at doorstepTravel Medicine and Infectious Disease, 2023
- A Brief Introduction to Avian Influenza Virus2020
- Safety and immunogenicity of influenza A(H5N1) vaccine stored up to twelve years in the National Pre-Pandemic Influenza Vaccine Stockpile (NPIVS)Vaccine, 2019
- Epidemiology, Evolution, and Pathogenesis of H7N9 Influenza Viruses in Five Epidemic Waves since 2013 in ChinaTrends in Microbiology, 2017
- Avian influenza A (H7N9) virus infection in humans: Epidemiology, evolution, and pathogenesisInfection, Genetics and Evolution, 2014
- An overview of the epidemiology of avian influenzaVaccine, 2007