Early Detection of H5N1: The Role of Rapid Antigen Testing in Antarctic Research

Posted on 2026-09-24

Three Decades of Avian Flu 

The strain of Avian Influenza known as HPAI H5 has been known to scientists since 1959 when it was first detected in domesticated chickens in Scotland. However, its currently circulating highly pathogenic sub-strain, H5N1, was first identified in domesticated waterfowl in southern China in 1996 (1). As this virus was a new occurrence, total numbers of infected birds were never confirmed. However,1.3 million birds were culled to prevent the spread, and 18 humans were infected with the virus leading to 6 deaths (1).  

H5N1 was not widely detected again until 2003, when it re-emerged in China and spread to several other countries across Asia. By 2005 it had reached poultry farms in Africa, the Middle East, and as far as Europe (1) due to migrating wild birds from Asia. This resulted in 74 human deaths from 142 confirmed cases globally. 

For nearly two decades H5N1 had not left the Eurasian continent, until late 2021 when the virus was detected in wild birds in the United States and Canada, causing outbreaks in poultry farms in February 2022 (1).

H5N1 Has Reached the Antarctic 

A study starting in 2023 by Simon B.Z. Gortez et al has now confirmed that H5N1 (specifically clade 2.3.4.4b) has reached Antarctica (3). H5N1 cases have been confirmed mainly in South Polar Skuas (Stercorarius Maccormicki) and Brown Skuas (Stercorarius antarcticus), but one case was detected in the Kelp Gull (Larus dominicanus). 

The detection of H5N1 in Antarctica confirms the presence of the virus on all seven of Earth’s continents, verifying it as a worldwide threat to avian life. Given the continent's largely undisturbed and delicate ecosystem, an outbreak could have significant ecological consequences, impacting the entire ecosystem rather than solely bird populations. 

Thankfully, at present, no signs of infection were observed in other marine life including marine mammals like seals (3).  

How the Study was Conducted 

To reduce the potential for contamination, no live birds were handled during the study. Instead, fresh faecal samples were collected from observed birds and the dark material from the faeces was swabbed within one minute of excretion. 

Swabs were also used to collect samples from dead birds. Both the brain cavity and the cloaca of the carcasses were swabbed for sampling. 

As part of the sampling process, researchers used rapid test kits to assess the presence of H5N1 in the field before conducting further laboratory testing.

Rapid Testing 

Rapid test kits provide a starting point for research and are recommended by the study as a first port of call when studying viral impacts on animal ecosystems. 

During the study, the first swab from each bird was tested for H5N1 immediately using rapid test kits. Results were typically available within 15 minutes; however, due to the extreme cold conditions encountered during the study, a small number of results did not become clear until up to three hours later. 

The second swab from each sample was stored in universal transport medium at room temperature for up to 17 days, followed by a further five days at 4°C. The samples then underwent RNA extraction and were analysed using reverse transcriptase real-time PCR (RT-qPCR). 

Researchers then compared the results of their in-field rapid tests with the lab based RT-qPCR results and found a 90% agreement across 23 carcasses and 7 live bird faecal samples. 

The researchers stated “We found rapid antigen tests successfully detected avian influenza virus in South Polar Skua carcasses—later confirmed as HPAI H5N1 via RT-PCR". 

The study highlights that rapid test kits can serve as a foundational first step in research projects for several reasons: 

1. They are lightweight and portable, making them well suited to fieldwork. 
2. Initial results are available quickly, typically within 15 minutes. 
3. No additional laboratory equipment is required to interpret test results. 

Future Threats 

As no visible signs of infection were observed, species other than Skuas and Kelp Gulls were not tested during the study. However, this does not rule out the possibility of the virus spreading to other seabird populations. 

Recent evidence highlights this risk. In Australia, the first case of H5N1 was recently detected in a penguin (5). Should the virus spread from Skuas to Antarctic penguin colonies, the consequences for the ecosystem could be severe. While the Antarctic Skua population is estimated at around 45,000 individuals (6)(8), the combined population of penguin species across Antarctica is estimated to exceed 44 million (7). 

This underlines the importance of proactive surveillance and research, with rapid antigen testing kits playing a key role in enabling early detection and field-based monitoring. 

At Abbexa, we support scientists worldwide with a wide range of rapid test kits for the detection of avian influenza. In addition to the H5 strains discussed in this article, our portfolio also includes tests for H7 and H9 variants, available below and until 30/11/2026, we are offering a 25% discount across our entire rapid test kit range, available here.  

References

1. CDC, 2023, Emergence and Evolution of H5N1 Bird Flu, archive.cdc.gov. https://archive.cdc.gov/www_cdc_gov/flu/avianflu/communication-resources/bird-flu-origin-infographic.html 
2. Robert Roos, 2006, Year-end Review: Avian flu emerged as a high-profile issue in 2005, CIDRAP, University of Minnesota. https://www.cidrap.umn.edu/avian-influenza-bird-flu/year-end-review-avian-flu-emerged-high-profile-issue-2005 
3. Simon B. Z. Gorta, 2026, Ecological implications and lessons from high pathogenicity avian influenza H5N1 2,3,4,4b in Antarctica, British Ecological Society, Volume 7 Issue 3. https://doi.org/10.1002/2688-8319.70267. https://besjournals.onlinelibrary.wiley.com/doi/full/10.1002/2688-8319.70267 
4. Phoebe Weston, 2024, Scientist confirm first cases of bird flu on mainland antarctica, The Guardian. https://www.theguardian.com/environment/2024/feb/26/scientists-confirm-first-cases-of-bird-flu-on-mainland-antarctica 
5. Lisa Cox, 2026, First Australian death of little penguin with H5 bird flu confirmed on Phillip Island, The Guardian. https://www.theguardian.com/world/2026/aug/15/little-penguin-found-dead-with-h5-bird-flu-on-victorias-phillip-island 
6. J Westrip,Brown Skua, datazone.birdlife.org. https://datazone.birdlife.org/species/factsheet/brown-skua-catharacta-antarctica Date Accessed: August 2026 
7. World population review, 2026, Penguin Population by Country 2026. https://worldpopulationreview.com/country-rankings/penguin-population-by-country. Date Accessed: August 2026 
8. J Westrip,South Polar Skua,datazone.birdlife.org. https://datazone.birdlife.org/species/factsheet/south-polar-skua-catharacta-maccormicki. Date Accessed: August 2026 

Written by Rich Balfour