Suspected H5 in Elephant Seals on Sub-Antarctic Island
Australian researchers aboard the RSV Nuyina have reported unusual mortalities among elephant seals on sub-Antarctic Heard Island, with clinical signs suggestive of H5 avian influenza infection. If confirmed, this would represent the first detection of H5 virus in an Australian sub-Antarctic territory. Heard Island, part of the Heard Island and McDonald Islands external Australian territory, lies approximately 4,000 km southwest of Perth and 1,700 km north of Antarctica in the Southern Ocean.
Australia remains the only continent without confirmed cases of the highly pathogenic H5 strain. A positive finding on Heard Island is not expected to significantly increase the risk to mainland Australia. No abnormal mortality has been observed among other local wildlife species, including penguins and seabirds. Diagnostic samples will be sent to the CSIRO Australian Centre for Disease Preparedness for confirmation once RSV Nuyina returns to Australia in mid-November, and laboratory results are anticipated several weeks thereafter.
