Australia's chief health officer Brendan Murphy has defended a decision to recommend public gatherings of more than 500 people are cancelled.

Home Affairs Minister Peter Dutton was diagnosed with the COVID-19 disease yesterday, after attending a Cabinet meeting with the PM on Tuesday. But the Prime Minister’s office insists there’s no need for Mr Morrison to be tested nor self-isolate.

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More than 200 cases of the coronavirus have now been confirmed across Australia, and three people have died.

There are 112 cases in New South Wales, 36 in Victoria, 46 in Queensland, 19 in South Australia, 17 in Western Australia, five in Tasmania, one in the Northern Territory, and one in the ACT.

On Thursday afternoon there were 141 virus cases across Australia. That jumped to 200 by the same time on Friday – an increase of 41 per cent.

The PM introduced a ban on public gatherings of more than 500 people from Monday.

Prof Murphy said this was the easiest way to stop the spread of the virus. But if there were more community transmissions it could lead to more restrictions, such as schools and public transport closing.

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