Scott Morrison has described the coronavirus outbreak as a global health crisis, warning the economic impacts will stretch far beyond Australia's tourism and education sectors.

As the nation grapples with the economic fallout, the prime minister confirmed 15 people who returned to Australia had been cleared of the virus, while seven others from the Diamond Princess cruise ship have mild symptoms.

Mr Morrison described the virus as an "unknown global shock".

"This is not like a global financial crisis. This is a global health crisis," he told reporters in Canberra on Tuesday.

Treasurer Josh Frydenberg said his department had not yet finalised its advice on the economic impacts.

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"The message is very clear, the impact will be more significant than the bushfires, and it plays out more broadly across the Australian economy," Mr Frydenberg said.

The prime minister said speculation about the impact on the budget bottom line was unhelpful.

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"Hands up those who thought there was going to be a coronavirus epidemic when the budget was released last May? Of course no one did," Mr Morrison said.

Australia has imposed a strict travel ban on visitors arriving from China.

The prime minister appears reluctant to extend the ban to other countries where the virus has taken hold.

"We have no advice from the medical experts to suggest that that should be done at this point," he said.