Australia has confirmed its first case of bird flu in a mammal after the positive testing of a long-nosed fur seal in South Australia.

The sick seal was found in Beachport, south of Adelaide, with the CSIRO’s Australian Centre for Disease Preparedness (ACDP) confirming 11 new H5 bird flu cases, including the first confirmed detection in a mammal, on Saturday.

Federal Agriculture Minister Julie Collins said although sad, the news was not unexpected.

Know the news with the 7NEWS app: Download today

“This is sadly our first confirmed case of H5 bird flu in a mammal in Australia,” she told reporters in Hobart.

“Although this is a concerning development, it is not unexpected for us to start to see infection in other wildlife, particularly in marine mammals, particularly in areas where there are high infection rates in wild birds.”

Federal Agriculture Minister Julie Collins said although sad, the news was not unexpected. Credit: 7NEWS

Collins said the seal does not appear to be associated with other sick or dead marine mammals.

“An infection of this individual animal is likely to have occurred due to exposure to infected wild birds or the environment that they share,” she said.

The minister stressed that there is no evidence of infection in Australia’s poultry or agriculture systems at this stage.

Australia has had 298 recorded positive H5 bird flu events. Credit: AAP

Australia has had 298 recorded positive H5 bird flu events since the outbreak several months ago, including the confirmed death of a little penguin on Phillip Island last week.

A program to vaccinate more than 5,000 little penguins across Phillip Island and St Kilda began on Monday.