Further analysis will establish whether seven confirmed cases of bird flu in wild seabirds were locally transmitted, authorities have announced.
Australian Chief Veterinary Officer Beth Cookson said on Tuesday that testing at CSIRO's Australian Centre for Disease Preparedness had confirmed H5 bird flu in seven greater crested terns found in South Australia's southeast.
One was found at Cape Jaffa, one at Port MacDonnell, and five around Southend Jetty, near Beachport.
SA Primary Industries Minister Clare Scriven said analysis was continuing on the genetic makeup of the virus ''to understand exactly how related they are to other detections overseas as well as within Australia''.
''That will be informative to whether there is spread between local birds, or whether these isolated detections,'' she said.
SA chief veterinary officer Skye Fruean said they hoped to receive the final results on Wednesday.
There have now been 27 confirmed or presumed positive detections of H5 bird flu in Australia in the states of SA, Western Australia, NSW and Queensland. All have been wild seabirds found in coastal locations.
There have been no detections of H5 bird flu in poultry, captive birds, or pets and other wildlife or livestock, and no evidence of any mass mortality events.
Ms Scriven said she had attended an industry preparedness day on Tuesday and had seen the technology that would be deployed in the event of an outbreak in a poultry facility.
Ms Fruean said the state had a ''first-class, world-class surveillance system''.
''We're picking it up incredibly early, so we've got a really sensitive tool at our fingertips in terms of being able to understand where this is happening in the environment,'' she said.
''So while we might not pick up every single case, we're obviously picking it up really early to understand how it is moving through birds.''
SA had been engaged in its biggest surveillance operation in more than 40 years, Ms Scriven said.
''A great deal of that has been aerial surveillance by helicopters and fixed-wing aircraft, as well as literally boots on the ground,'' she said.
''People are on the alert … we've had more than 2700 reports to date to the emergency animal disease hotline since the first detection.''
