Wild birds have experienced unprecedented, near-global mass mortalities since 2021, driven by outbreaks of high-pathogenicity avian influenza virus (HPAIV) H5N1 lineage 2.3.4.4b. Managing this panzootic requires identification of transmission pathways. We investigated potential HPAIV transmission via kleptoparasitism (food theft) by examining the distribution, behaviors, and movements of two globally widespread and commonly kleptoparasitic seabird families: Fregatidae (frigatebirds) and Stercorariidae (skuas). These kleptoparasites force other seabirds (targets) to regurgitate food, which the kleptoparasite then ingests, potentially facilitating direct transfer of viral particles from target to kleptoparasite. Scavenging and predation probably contribute further to viral spread. Although frigatebirds use kleptoparasitism on a year-round basis, skuas more commonly do so outside of the breeding season. Both frequently forage, disperse, or migrate across oceans and hemispheres. Dense aggregations of kleptoparasitic and target seabirds at breeding and/or roosting sites may facilitate the spread of HPAIV. In addition, the migration of these species could also facilitate broadscale geographic spread of HPAIV. Surveillance of kleptoparasites for HPAIVs could aid in early detection and may be important for seabird conservation.

中文翻译：

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海鸟的偷窃寄生症——全球禽流感病毒传播的潜在途径


自 2021 年以来，在高致病性禽流感病毒 （HPAIV） H5N1 谱系 2.3.4.4b 疫情的推动下，野生鸟类经历了前所未有的近乎全球的大规模死亡。管理这种泛动物病需要确定传播途径。我们通过检查两个全球广泛且常见的盗贼寄生海鸟科的分布、行为和运动，研究了通过偷窃寄生（食物盗窃）的潜在 HPAIV 传播：Fregatidae （军舰鸟） 和 Stercorariidae （贼鸥）。这些窃贼寄生虫迫使其他海鸟（目标）反刍食物，然后偷窃寄生虫摄入食物，从而可能促进病毒颗粒从目标直接转移到偷窃寄生虫。清道夫和捕食可能会进一步促进病毒的传播。尽管军舰鸟全年都使用盗贼寄生，但贼鸥更常在繁殖季节之外这样做。两者都经常在海洋和半球觅食、分散或迁徙。盗贼寄生海鸟和目标海鸟在繁殖和/或栖息地的密集聚集可能促进 HPAIV 的传播。此外，这些物种的迁移也可能促进 HPAIV 的广泛地理传播。监测 HPAIV 的盗窃寄生虫有助于早期发现，并且可能对海鸟保护很重要。