Abstract Title
Skua die-off from high pathogenicity avian influenza on Beak Island, Antarctica, 2023–2024
Abstract
Over the last three decades, outbreaks of high pathogenicity avian influenza viruses (HPAIV) of the Goose/Guangdong lineage (Gs/Gd) have caused mass mortalities in a variety of wild and domestic bird species, but also mammals, almost worldwide. In February 2024, HPAIV of the currently dominating genetic clade 2.3.4.4b spread to Antarctica for the first time, raising concern on the potential impacts to endemic wildlife populations that aggregate in individual-dense colonies to breed during the Antarctic summer. In response to this, the Australis expedition was set up in March 2024 to explore the occurrence and spread of HPAIV in the Antarctic Peninsula. At Beak Island, part of the James Ross Island group off the northwestern Weddell Sea, we identified an unusual mortality event of brown and south polar skuas (Stercorarius spp.), with over 40 individuals found dead. We examined 10 carcasses, and detected HPAIV by RT-qPCR in multiple tissues, with high viral RNA levels in the brain, matching confirmations via immunohistochemical detections. These observations show that HPAIV Gs/Gd can also cause unusual mortality events in wildlife in Antarctica. We (i) conclude that HPAIV H5 represents a potential threat to conservation of skuas and (ii) highlight the role of skuas both as an early indicator for the local presence of HPAIV, and as possibly being involved in long-distance virus spread.
Co-Author(s)
Anne Günther1a, Matteo Iervolino2a, Lineke Begeman2, Theo M. Bestebroer2, Lonneke Leijten2, Beatriz Bellido-Martin2, Dirk Höper1, Meagan Dewar3, Florencia Soto4, Antonio Alcamí5, Begoña Aguado5, Martin Beer1, Timm Harder1, Peter van Run2, Simeon Lisovski6, Ben Wallis7, Adam Coerper7, Alice Reade7, Ralph E.T. Vanstreels8b and Thijs Kuiken2b
1 Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Germany
2 Department of Viroscience, Erasmus University Medical Center, the Netherlands
3 Future Regions Research Centre, Federation University Australia
4 Instituto de Biología de Organismos Marinos (IBIOMAR-CONICET), Argentina
5 Centro de Biología Molecular Severo Ochoa, CSIC, Spain
6 Polar Terrestrial Systems, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Potsdam, Germany
7 Ocean Expeditions Support Vessel S/V Australis
8 Karen C. Drayer Wildlife Health Center, One Health Institute, School of Veterinary Medicine, University of California - Davis, United States
a Shared-first authors
b Shared-last authors
Abstract Category
Notable outbreaks, field and molecular epidemiology, and surveillance in wild birds