Tuesday, October 24, 2023

Bird flu detected in Antarctica for first time as fears grow of mass wipe-outs


Harriet Barber
Tue, 24 October 2023

Penguins gathered together on the shoreline in Antarctica 
- Ant Photo Co/Ant Photo Co

Bird flu has been detected in Antarctica for the first time, raising fears of a mass wipe-out of the continent’s avian populations.

The highly-pathogenic H5N1 strain has already killed millions of birds across the globe over the past year, and has now hit one of the most important breeding grounds on the planet.

Following reports of the unexplained deaths of skuas – a scavenging bird – on Bird Island in South Georgia, the British Antarctic Survey (BAS) sent samples for testing.


On Monday 23 October, the results came back as positive for H5N1.

“Mortality is growing,” said Dr Norman Ratcliffe, a seabird ecologist with the British Antarctic Survey, in an interview with the Telegraph. “It’s really worrying. Bird Island is one of the most exceptional habitats – the variety and density of birds is astonishing – so it’s very concerning that it has arrived in such an important location.”
‘When it takes hold it can spread quickly’

South Georgia is home to several species of albatrosses, macaroni and gentoo penguins, and northern and southern giant petrels. Experts now fear these birds could also be hit by the disease, which is transmitted mostly through faeces or direct contact.

“Some of these colonies are very dense, and when it takes hold it can spread quickly,” said Dr Ratcliffe. “You can’t really limit the movements of wild birds.”

Researchers had been nervously waiting for H5N1 to be detected in Antarctica following a global surge in the disease since last autumn.

In an interview with The Telegraph last month, Dr Jane Rumble, the head of polar regions for the Foreign, Commonwealth and Development Office, said: “We’re saying when, not if. It could be absolutely devastating.”

Scientists had been hoping that avian influenza would not reach South Georgia, due to its relative isolation from the continent. “Clearly that hope was misplaced,” said Dr Ratcliffe.

Scientists first noticed potentially symptomatic cases on Bird Island in late September and counted 29 dead skuas, when normally only three or four would be expected.

The BAS has said it is likely that the disease has spread by birds returning from their migration to South America, where cases are high.

Chile and Peru alone have lost more than 500,000 wild birds and 20,000 mammals, according to a report by the OFFLU, a global network of flu experts. Actual mortality is thought to be many times higher due to difficulties in testing.

As Antartica has never had an outbreak of the highly pathogenic bird flu circulating the globe, its species are thought to have little immunity to the virus.

As a result of the confirmed cases, the majority of scientific field work involving animal handling has been suspended. Enhanced biosecurity measures had already been introduced this season in preparation.

The World Health Organisation has recorded increasing numbers of the H5N1 strain among mammals, which raises concerns that the virus might adapt to infect humans more easily.

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