The University of Queensland closed after three students tested positive for the virus. Western Australia, like New South Wales, stopped schools from organising gatherings of over 500. Susan McDonald, a Queensland senator, said she was infected with the virus. New South Wales Liberal senator, Andrew Bragg, was the third Australian politician to test positive. On 18 March, a human biosecurity emergency was declared by the Governor-General, David Hurley, under Section 475 of the "Biosecurity Act 2015".