Anyone in hospital with "an unusual pneumonia" is now being tested for coronavirus, Chief Medical Officer Brendan Murphy said on Wednesday, as an eighth case was confirmed among Australians evacuated from the Diamond Princess cruise ship.
Health Minister Greg Hunt said the Victorian man had already been in isolation because his partner had contracted the virus. A possible ninth case was also being tested on Wednesday.
As the situation worsened outside China, with the virus spreading to other parts of Italy, an American reported to have tested positive in South Korea, and two Iranian MPs testing positive, including the deputy health minister, Australian authorities continued to reassure people they are prepared.
Professor Murphy said the virus could be in the wider Australian community already, but with more than 3000 tests to date, there had been only 15 positives.
"We have had a very advanced testing program and our doctors and hospitals around the country have had a low threshold for testing anyone who's had a relevant travel history and we haven't found anybody except those 15 original Hubei cases and the eight cases from the Diamond Princess," he said.
"That's not to say that someone who's come originally from China through another country isn't here already we are always on the lookout for that. And anyone who's got an unusual pneumonia is now being tested."
In Canberra, 93 people had been tested by Wednesday afternoon, all negative. In Sydney, cases remained at four, with 213 under investigation.
Australia has upped its travel advice for northern Italy and Iran to match Japan and South Korea, warning travellers to take "a high degree of caution".
But there are ongoing hints that Australia might soon relax its ban on university students from China.
Authorities met on Wednesday to consider the student ban with no outcome by evening, but Professor Murphy said cases were seemingly more under control outside of Hubei in China.
"We have to be very confident about the data before we accept that," Professor Murphy said.
"So if there's any more relaxation it would be very gentle and under the supervision of the state health authorities. That would be a decision for the government to make, the medical advice is that we should be fairly cautious."
Health Minister Greg Hunt said Australia had taken the approach of "acting early, acting hard".
Professor Raina MacIntyre, head of biosecurity at UNSW's Kirby Institute, has modelled a "severe scenario" in Australia under which about 50 per cent of the population could catch the virus. Five per cent of those could end up in intensive care and 3 per cent could die, she estimates, based on Australia having an older population than China.
But Australian National University infectious diseases expert Peter Collignon said such figures were speculation with very little basis. While the spread was worse than he had expected, with Iran now the big concern, Professor Collignon said he expected the death rate to be about 10 times lower than currently estimated. He based that on the swine flu experience where early death rates appeared to be about 6 per cent but once the real infection rate was established, the death rate was less than one in 1000.
While coronavirus was clearly more dangerous for people in their 70s and 80s, for people with underlying health conditions and for smokers, very young people either didn't get it or had "such mild symptoms nobody notices". Among Chinese health workers infected the death rate appeared to be about 0.3 per cent.
Professor Collignon said Australia should be prepared for a very widespread infection rate but that wasn't inevitable.
He pointed to the clustering of outbreaks to date, including on the cruise ship and the Korean church group. In the US of the 57 cases, 40 are connected to the Diamond Princess, the New York Times reports.
"The honest answer is we don't know," Professor Collignon said. "My own view is that it's still possible that this might come under control and disappear [although] I wouldn't put a lot of money on it because of what's happening in Iran ... When you have the assistant health minister coughing and spluttering on television the day before he's diagnosed, it's obviously much more widespread."
Professor Murphy said if virus outbreaks did occur in Australia, the response would depend on where and how big. If an outbreak was small, authorities would move quickly to isolation measures. If it was in a particular state, schools could be closed and hospitals reconfigured to deal with cases. The focus would be on slowing the spread of cases to put less pressure on the health system and make it easier to handle an outbreak, he said. Aged care was a big part of planning.
A declaration of pandemic would not change Australia's response, he said.
"We will just continue what we are doing now," he said. "It's just a label that says there's sustained community transmission in several countries."
Mr Hunt said there had been 80,410 cases and 2707 deaths worldwide by Wednesday lunchtime.
Universities are seeking to soften the blow for students, with Melbourne University now offering up to $7500 to reimburse expenses such as flights and accommodation. The Australian National University is waiving fees for new students who enrol in remote courses for the first semester, and for existing students, the university is allowing them to drop the courses without financial or academic penalty until June 3. They can also repeat the courses if they fail without having to pay a new set of fees.
Olympics Australian chief of mission Ian Chesterman said the coronavirus was being taken very seriously, but the games were expected to go ahead.
"We've not had any advice from the [International Olympic Committee] that there's any other plan other than to start the games on July 24. They remain confident in the Japanese authorities to be on top of this, they remain confident that the games will proceed."
Mr Hunt said assessments about the Tokyo Olympics would be made close to the time, with athletes advised "for the moment, just keep training".