Researchers Confirm H5N1 Bird Flu Behind Subantarctic Dieoffs Of Elephant And Fur Seals

A virology team has confirmed the first bird flu infections in elephant and fur seals in the sub-Antarctic region, as the highly contagious H5N1 virus continues to spread around the world. Researchers previously reported the mass deaths of seals and that a number of elephant seals on South Georgia island – a UK overseas territory in the southern Atlantic Ocean – had been exhibiting symptoms of avian flu. But while seabird cases were confirmed, the seal infections were classed as suspected, pending lab results.

The first known cases of H5N1 were detected in the Antarctic region in October among brown skua on Bird Island, off South Georgia. Two months later, hundreds of elephant seals were found dead. There have also been increased deaths of fur seals, kelp gulls and brown skua at several other sites. Marco Falchieri, a scientist in the UK Animal and Plant Health Agency’s (APHA) influenza and avian virology team, which collected the South Georgia samples that tested positive for bird flu. He said he saw about 20 dead elephant seals. “Emotionally it is almost heartbreaking to see so many dead seals.”

Other seals were showing respiratory signs of bird flu, he said, citing “coughs, sneezing, ocular discharge, nasal discharge, slow head shaking and tremors”.

Falchieri said the death toll on South Georgia was probably about 100, mainly elephant seals, who appear to be more affected than fur seals. “My worst fear is an adaptive mutation to mammals, which we are not seeing in these new samples, but we need to keep monitoring,” he said. An adaptive mutation, he added, “could mean it becomes a mammalian-adapted virus, and consequently increases risk for humans too”.

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https://www.theguardian.com/environment/2024/jan/11/mass-seal-deaths-antarctic-southern-atlantic-south-georgia-bird-flu-aoe