The deadly H5N1 strain of bird flu is suspected to have reached mainland Australia for the first time. Federal Agriculture Minister Julie Collins announced this afternoon that a wild migratory bird suspected to have avian influenza was detected in south-west Western Australia. The H5N1 strain of bird flu reached Heard Island, an extremely remote Australian territory, late last year, and is now suspected to have been detected on the mainland. AP The bird had fallen ill and has since died.