Avian flu has made its chilling debut in Antarctica, sparking concerns for the vulnerable populations of penguins and seals that have never encountered the deadly H5N1 virus before. The arrival of the virus is shrouded in uncertainty, with scientists warning of possible "catastrophic breeding failure" among the delicate wildlife populations in the region.
The virus was detected in brown skuas, a scavenging bird species, on Bird Island, which forms part of the British overseas territory of South Georgia and the South Sandwich Islands. These migratory birds likely brought the virus with them from South America, where bird flu has already claimed the lives of around 500,000 seabirds and 20,000 sea lions in Chile and Peru alone.
The current outbreak of the highly contagious H5N1 variant, which originated in 2021, has already taken a devastating toll on millions of wild birds. Concerns have long been raised about the potential impact on Antarctic wildlife, as many species are found exclusively in this remote region and have never been exposed to avian flu viruses.
Bird Island, situated several hundred miles off the southeast coast of the Falkland Islands, is renowned as one of the world's most biodiverse hotspots. It is home to approximately 50,000 breeding pairs of penguins and an astounding 65,000 pairs of fur seals. The island also provides a refuge for numerous endangered bird species. The introduction of avian flu into this fragile ecosystem could lead to "catastrophic breeding failure and mortality events," warned Dr. Meagan Dewar, chair of the Antarctic Wildlife Health Network.
The unusual deaths of migratory brown skuas on Bird Island prompted researchers from the British Antarctic Survey to collect swabs for testing in the UK. The results confirmed the presence of H5N1 in this remote corner of Antarctica. It is believed that the migratory birds brought the avian flu with them from South America.
H5N1, a subtype of avian flu classified as highly pathogenic avian influenza (HPAI), is notorious for its severe impact and high mortality rate among poultry populations. In Peru and Chile alone, more than 500,000 seabirds and over 20,000 sea lions have succumbed to HPAI H5N1 this year, according to the Scientific Committee on Antarctic Research (SCAR). The ongoing outbreak of H5N1, which started in 2021, has claimed the lives of countless birds. Earlier this year, thousands of sea lions in South America were found dead due to H5N1.
The first reported outbreak of this strain in humans occurred in Hong Kong in 1997, and it has since spread worldwide. According to the journal Nature, the current outbreak is caused by a highly virulent form of the H5N1 sub-type.
The strain initially emerged in Europe in 2020 and quickly spread to several countries. In 2022, the virus was first detected in South America, rapidly spreading from Colombia to Chile within a mere three months.