St. Helena - Influenza A viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

[Lance]

​https://wahis.woah.org/#/in-review/6354

 

[Pathfinder]

​

​

/https://en.wikipedia.org/wiki/Gough_Island

----------------------------------------------------------
More from the WOAH report posted above:
...
AFFECTED POPULATION DESCRIPTION

On 12th September 2024, a dead Tristan (Brown) Skua (Stercorarius antarcticus hamiltoni) was found at the Gough Island helipad. The following day, a live skua was observed showing suspicious signs of HPAI, including head drooping, lethargy and weakness, and was later reported dead. Between the 12th and 15th September, a total of four skuas were found dead from suspicious causes. Three carcasses were swabbed on the 20th of September and all were confirmed POSITIVE for H5N1 HPAIV by the Animal and Plant Health Agency (Weybridge laboratory) in the UK on the 24th of October 2024. On the day of sampling, the fourth carcass could not be found and was probably taken away by a scavenging skua. Since then, no further signs of HPAI among skuas or in other seabirds breeding on Gough Island, have been observed.
...

​

 

[Pathfinder]

​
Investigating high pathogenicity avian influenza virus incursions to remote islands: Detection of H5N1 on Gough Island in the South Atlantic Ocean

Posted January 22, 2026.
Download PDF​

View ORCID ProfileAntje Steinfurth, View ORCID ProfileJoshua G. Lynton-Jenkins, View ORCID ProfileJaimie Cleeland, View ORCID ProfileBenjamin C. Mollett, View ORCID ProfileHolly A. Coombes, Andrea Moores, Robyn Neal, Ben Clifton, Marco Falchieri, View ORCID ProfileChristopher W. Jones, View ORCID ProfileMichelle M. Risi, View ORCID ProfileSusannah Gold, View ORCID ProfileJoe James, View ORCID ProfilePeter G. Ryan, View ORCID ProfileJacob Gonzalez-Solis, View ORCID ProfileAshley C Banyard
doi: https://doi.org/10.1101/2025.09.06.674618

This article is a preprint and has not been certified by peer review [what does this mean?].
...
Abstract

1. Understanding the mechanisms underlying the emergence and spread of high pathogenicity avian influenza virus (HPAIV) is critical for tracking its global dissemination, particularly via migratory seabirds, given their role in transmission over long distances. Scavenging seabirds, such as skuas, may act as both reservoirs and vectors, and have been linked to multiple outbreaks since 2021. Here, we report the detection of HPAIV H5N1 clade 2.3.4.4b in three Tristan skua (Stercorarius antarcticus hamiltoni) carcasses on Gough Island in the central South Atlantic Ocean. To investigate potential incursion routes, we combined genomic analyses with year-round tracking data from global location sensors. Although migratory movement patterns suggested southern Africa as the most obvious pathway, the strain detected on Gough Island was more closely related to that identified in South Georgia, indicating that infection may have occurred during the pre-laying exodus, when skuas disperse into frontal waters south of the island. No further cases have been confirmed for Gough, but more systematic monitoring is needed to understand the dynamics of virus infection. The detection of HPAIV H5N1 in skuas on Gough Island highlights the importance of continued vigilance, proactive and geographically inclusive surveillance strategies, and biosecurity measures globally, alongside efforts to reduce other pressures on globally important seabird populations to help strengthen their resilience.

​...

https://www.biorxiv.org/content/10.1101/2025.09.06.674618v2