Iceland as Stepping Stone for Spread of Highly Pathogenic Avian Influenza Virus between Europe and North America

• Published in: Emerging Infectious Diseases
• Main Authors: Anne Günther, Oliver Krone, Vilhjalmur Svansson, Anne Pohlmann, Jacqueline King, Gunnar Thor Hallgrimsson, Kristinn Haukur Skarphéðinsson, Heiða Sigurðardóttir, Stefán Ragnar Jónsson, Martin Beer, Brigitte Brugger, Timm Harder
• Format: Article in Journal/Newspaper
• Language: English
• Published: Centers for Disease Control and Prevention 2022
• Subjects: highly pathogenic avian influenza virus; influenza virus; viruses; highly pathogenic avian influenza; avian influenza; HPAIV; Medicine; R; Infectious and parasitic diseases; RC109-216; Iceland; North Atlantic
• Online Access: https://doi.org/10.3201/eid2812.221086; https://doaj.org/article/2808dc3291134d4ab0cbf54959348bf5

Highly pathogenic avian influenza viruses (HPAIVs) of hemagglutinin type H5 and clade 2.3.4.4b have widely spread within the northern hemisphere since 2020 and threaten wild bird populations, as well as poultry production. We present phylogeographic evidence that Iceland has been used as a stepping stone for HPAIV translocation from northern Europe to North America by infected but mobile wild birds. At least 2 independent incursions of HPAIV H5N1 clade 2.3.4.4b assigned to 2 hemagglutinin clusters, B1 and B2, are documented for summer‒autumn 2021 and spring 2022. Spread of HPAIV H5N1 to and among colony-breeding pelagic avian species in Iceland is ongoing. Potentially devastating effects (i.e., local losses >25%) on these species caused by extended HPAIV circulation in space and time are being observed at several affected breeding sites throughout the North Atlantic.