Human infections with avian influenza A(H5) viruses with potential pandemic risk: 1997–2025

作者：Wei Wang, Jiabao Xing, Hui Jiang, Feiteng Lu, Haoxuan Huang, Yuqian Zhang, Andi Sun, Yi Han, Jian Lü, Benjamin J. Cowling, Peter Horby, Richard J. Webby, Timothy M. Uyeki, Hongjie Yu · 发表于：National Science Review · 年份：2025 · DOI：10.1093/nsr/nwaf471 · 被引用次数：3 · 研究领域：Influenza Virus Research Studies、Zoonotic diseases and public health、Animal Disease Management and Epidemiology

ABSTRACT Highly pathogenic avian influenza (HPAI) A(H5) viruses have caused sporadic human infections since 1997, with recent detections in the Americas and Asia. However, the evolutionary dynamics of different HPAI A(H5) viruses at the animal–human interface, along with their associated disease severity, propensity for animal-to-human (zoonotic) spillover, and human-to-human transmission potential, remain unclear. Here, we combine available genetic and epidemiological data with mechanistic models to better understand the global spread of HPAI A(H5) viruses that spilled over to humans in 1997–2025. Analysis of 7445 subsampled hemagglutinin gene sequences revealed frequent regional succession of HPAI A(H5) virus clades that varied by geographic location. The 1104 reported human HPAI A(H5) cases exhibited subtype- and clade-specific heterogeneity in age, gender, and exposure sources (p < 0.001). After adjusting for under-reporting, we estimated case-fatality risk to be low for HPAI A(H5N1) clade 2.3.4.4b (0.7%, 95%CI: 0.02%–3.9%) and for A(H5N6) clades 2.3.4x (0%, 0%–1.1%) and 2.3.4.4b (1.6%, 0.7%–3.2%), compared with other A(H5) clades (range: 4.7%–15.0%). We also show that, while the transmissibility of HPAI A(H5) viruses between humans remains very low to date (mean Rt: 0.10–0.23), zoonotic transmission has increased with the emergence of bovine-origin clade 2.3.4.4b (incidence: 7.85 per million people per year), relative to other avian-origin A(H5) clades (range: 1.5...