CANBERRA, July 31 (Xinhua) -- A growing outbreak of H5N1 avian influenza in South Australia (SA) will "almost certainly" spread to an endangered species of sea lion, an expert has warned.
Authorities in SA reported that Australia's first suspected case of the highly pathogenic strain in a seagull has been detected on the state's southeast coast.
It takes the total number of suspected cases of the strain in SA to 21 in addition to 19 confirmed cases.
As of Friday, the rest of Australia's states and territories had reported 14 confirmed cases of the strain, which was first detected on the mainland in June.
Of the 40 confirmed or suspected cases in SA, 33 have been reported since Monday, including four that were detected on Kangaroo Island off the state's south coast.
One of the Kangaroo Island cases was detected at Seal Bay, which is home to about 5 percent of the global population of the endangered Australian sea lion.
Wayne Boardman, a wildlife veterinarian from the University of Adelaide, told the Australian Broadcasting Corporation on Friday that historical events in South America have shown that sea lions and fur seals are particularly susceptible to the strain.
"The issue now with bird flu being found on Seal Bay is that it's almost certainly going to go from the birds into the sea lions," he said.
The H5N1 strain killed an estimated 30,000 sea lions in South America within six months in 2022 and killed an estimated 13,359 southern elephant seal pups on Australia's Heard Island in the Southern Ocean between August 2025 and January 2026.
The SA government on Wednesday announced that beach tours on Seal Bay would be temporarily suspended to protect local sea lion and seal populations.
Minister for Agriculture, Fisheries and Forestry Julie Collins told reporters on Friday that the government would continue working with experts to contain the spread of the strain. She said there has been no evidence of the virus in agricultural or poultry systems and the threat to human health remains low. ■
