Joint statement from the Scientific Committee on Antarctic Research (SCAR), Council of Managers of National Antarctic Programs (COMNAP), International Association of Antarctica Tour Operators (IAATO), and the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR).
Following visual observations on 22 December 2023 by winter-over team members from the national Antarctic program of Argentina, we can announce that High Pathogenic Avian Influenza (HPAI) is suspected in Antarctic Skuas (Stercorarius antárctica) in the Antarctic Treaty Area near Argentina’s Orcadas Station. In late October, cases of HPAI were confirmed in Brown Skua and Southern Fulmar but those animals were in the Sub-Antarctic islands and therefore not considered as being the first cases in the Antarctic.
Since October, we have been monitoring the situation carefully and visual observations strongly indicate HPAI in the Antarctic Treaty area today.
Confirmation of the cases through testing will be difficult as there are very few personnel in the area and limited sample collection and testing capabilities.
This is the first suspected occurrence of HPAI H5N1 in the Antarctic Treaty Area. A published risk assessment led by the SCAR Antarctic Wildlife Health Network (AWHN) had indicated there was a heightened risk that HPAI would present in Antarctic species this austral summer and a recent OFFLU statement confirmed and updated the risk. Because of that heightened risk, COMNAP, IAATO and SCAR have been working together to prepare for the virus’s arrival through natural migration of species.
Relevant authorities are also working to ensure that protocols are in place to prevent transmission to humans in that region, and to prevent the spread of the virus to other areas/species in Antarctica through human activity.
Avian influenza, known colloquially as ‘bird flu’ is caused by a virus that primarily effects birds but can also infect mammals including, in very rare instances, humans.
Bird flu has been around a long time, primarily affecting poultry, with first outbreaks in wild birds reported in 1961.[1] There are low pathogenic avian influenza (LPAI) viruses that wildlife species are infected with but that cause no clinical signs of disease.
There is a range of avian influenza subtypes. Of concern are subtypes H5 and H7, which may become highly pathogenic in poultry and then escape into wild bird populations. These highly pathogenic subtypes can cause up to 100% mortality in bird colonies.
Genetic assessment of the virus obtained from the Sub-Antarctic cases indicated spread from South America, likely through movement of migratory birds.[2] There are clear indications that the virus was brought to the Antarctic through natural migration and not through direct human activity or interactions with the birds.
HPAI H5N1 is the strain of HPAI that is currently causing unparalleled mortality of wild birds and mammals worldwide and threating population levels for some species already under multiple anthropogenic pressures.[3]
Antonio Quesada, COMNAP Chairman and Head of Spain’s national Antarctic program said, “We continue to be vigilant, looking for visual signs that birds in other areas might have the virus. We have a range of tools in place to assist us to monitor the situation and to communicate through our Antarctic regional networks as the global situation evolves and as the Antarctic situation changes”.
To date, globally, there are no sustained cases of human-to-human transmission and the current risk to humans in Antarctica remains low, especially with the protocols in place.[4] We continue to seek advice from the SCAR/COMNAP Joint Expert Group on Human Biology and Medicine in order to inform guidance for those operating in Antarctica.
The Food and Agricultural Organization of the United Nations (UN FAO) has noted that before 2005 when HPAI viruses spilled significantly from poultry into wild birds, HPAI in free-ranging wildlife was highly unusual. Now a new phase in the epidemiology of HPAI in wild birds has been entered and this better adapted virus is expected to continue to spread and cause further negative conservation impacts around the world.[5] Wild birds are both victims and vectors of the virus originating from within a poultry setting. In the sub-Antarctic, suspected cases in elephant seals are under investigation.
We have been preparing for and readied those who travel to Antarctica for the impact HPAI would have on Antarctic species. In mid-2022, SCAR began a collaboration with COMNAP and IAATO in regard to HPAI, specifically to clade 2.3.4.4b (HPAI H5N1).
Given the virus’ rapid spread through the northern hemisphere in 2021, its spread south into South America and South Africa in 2022, and the increase in cases in seabirds resulting in mass mortality events to date[6] the SCAR AWHN carried out a risk assessment for Antarctic and sub-Antarctic geographical areas and for wildlife groups published as “A Risk Assessment of HPAI in the Southern Ocean” [7].
Dr Meagan Dewar, leader of the SCAR Antarctic Wildlife Health Network (https://scar.org/library-data/avian-flu) and one of the co-authors of the SCAR risk assessment said, “The risk assessment gave us an early indication that gulls and skuas had the highest group vulnerability score for birds, and that fur seals and sea lions had the highest vulnerability score for mammals. The analysis indicated a heightened risk that HPAI would present in Antarctic species in 2023 or 2024 in the Antarctic Peninsula region and that is exactly what we are seeing.”
We will continue to monitor the situation in Antarctica and release information as and when it becomes available.
Notes
Follow the latest information from the SCAR Antarctic Wildlife Health Working Group at: https://scar.org/library-data/avian-flu.
Follow the latest global information at: https://www.woah.org/en/disease/avian-influenza/.
Follow the latest COMNAP guidance at: https://www.comnap.aq/heightened-risk-of-hpai-in-antarctica.
For further information from SCAR please email the SCAR secretariat at [email protected]
[1] W.B. Becker, “The isolation and classification of Tern virus: Influenza Virus A/Tern/South Africa/1961”, J. Hyg., Camb. (1966), 64, 309.
[2] A. Bennison, et al, Preprint: https://doi.org/10/1101/2023.11.23.568045.
[3] Food and Agricultural Organization of the United Nations (FAO) Scientific Task Force on Avian Influenza and Wild Birds statement on: H5N1 High pathogenicity avian influenza in wild birds – Unprecedented conservation impacts and urgent needs, July 2023, https://www.fao.org/3/cc6936en/cc6936en.pdf.
[4] Joint COMNAP/SCAR Expert Group on Human Biology and Medicine, Avian Influenza: A summary of “The Risk of Avian Influenza in the Southern Ocean: A practical guide for operators interacting with wildlife. With additional supporting information and guidance regarding impact of Avian Influenza in Humans”, June 2023, https://www.comnap.aq/s/Post-JEG-review-Avian-Influenza-A-summary-of-The-Risk-of-Avian-Influenza-in-the-Southern-Ocean-A-pra.pdf.
[5] FAO, July 2023.
[6] See SCAR, IAATO, COMNAP ATCM XLV (2022) IP101 “Heightened Risk of Avian Influenza in the Antarctic Treaty Area”, 28 April 2023.
[7] M. Dewar, M. Wille, et al, Preprint; https://doi.org/10.32942/osf.io/8jrbu.
Overview/Summary 1
What is Avian Influenza?
- A viral infection, meaning it is sickness caused by a virus.
- The virus is highly contagious among birds.
- The virus has been around globally since at least the early 1960s.
- Found in domestic poultry (such as chickens) and in many different types of wild birds.
- The virus has evolved over time. There are a range of types of avian influenza, some are low pathogenic (causing no disease in wild birds: all HA subtypes) and some are high pathogenic (associated with disease and death in poultry and wild birds: only the H5 and H7 subtypes). The virus can infect some mammals.
- Many Antarctic bird species are hosts for the low pathogenic type of virus and it does not cause concern.
- The type that has been confirmed in regard to the Antarctic species is Highly Pathogenic Avian Influenza of the Clade 2.3.4.4b. Commonly referred to as HPAI H5N1.
- To date, HPAI H5N1 had spread globally and rapidly but had not been found in the Antarctic Treaty Area (area of our planet below the 60-degree south latitude line).
- The virus has arrived through natural migration of wild bird species likely from South America and the sub-Antarctic into the Antarctic region this austral summer season 2023/24.
HPAI H5N1
- “HP” or “High Pathogenicity” means it makes infected birds [and some infected mammals] sick and causes mass mortality events where many infected animals die.
- An infected bird usually displays visible signs of the infection, such as nervousness, tremors, lack of coordination, lack of movement or odd movements, coughing/gasping for air, and swelling or redness around the eyes, neck and head. Although, some infected birds may not show any of these symptoms.
- Multiple dead animals in one area may be an indication that the virus is present.
What is the risk to humans?
- Globally, there have been increasing reports of outbreaks among mammals, with sporadic detection in humans reported but remaining very rare. To date, sustained human-to-human transfer has never been detected.
- Infections in humans can cause severe disease with a high mortality rate.
- The global human cases thus far are mostly linked to close contact with infected birds, or from their carcasses, body fluids or feces, and from virus contaminated environments[1].
What can we do?
- We can review and continue to strengthen our biosecurity protocols to avoid inadvertently introducing the virus intra-regionally or from home countries/deployment gateways.
- We can update our procedures for Antarctic activities, especially any activities that are near wildlife.
- We can remain vigilant and monitor Antarctic wildlife for signs of infection.
- There are national protocols for reporting confirmed avian flu cases in Antarctica.
Follow the latest global information at: https://www.woah.org/en/disease/avian-influenza/.
Follow the latest COMNAP guidance at: https://www.comnap.aq/heightened-risk-of-hpai-in-antarctica.
Follow the latest information from the SCAR Antarctic Wildlife Health Working Group at: https://scar.org/library-data/avian-flu.
[1] World Health Organization (WHO), https://www.who.int/news/item/12-07-2023-ongoing-avian-influenza-outbreaks-in-animals-pose-risk-to-humans, downloaded 21 August 2023.