What is coronavirus and will it become a global epidemic?
Brendan Murphy addressed reporters on Tuesday as airports stepped up their biosecurity measures for passengers arriving from China.
“You cannot absolutely prevent entry into the country of a disease like this,” he said.
"There's no way of preventing this getting into the country if this becomes bigger.”
His comments come as a Brisbane man was confirmed to be suffering from coronavirus symptoms and it is feared he could be the first Australian to have contracted the virus.
Professor Murphy moved to reassure Australians that they are “well prepared” for the virus which has so far 222 confirmed cases mainly across China as fears grow it could become a global epidemic.
It was confirmed the virus can be spread human to human and on Tuesday authorities revealed a fourth person had died from it.
Where are the most coronavirus cases?
Wuhan, the sprawling capital of central China's Hubei province, is the epicentre of the coronavirus with 198 cases – and visitors arriving from the city will face extra scrutiny.
The World Health Organisation began responding to cases of unexplained pneumonia in the city on December 31.
There are three direct flights a week from Wuhan into Sydney.
Each of these flights will now be met by biosecurity staff from Thursday.
"No international travellers have yet been confirmed as having this coronavirus in Australia and we already have well-established existing biosecurity measures at the border," Professor Murphy said.
Information will be displayed across all other points of entry into Australia to warn people who develop symptoms to seek urgent medical attention.
Australian authorities will also work with the Chinese media to get the message across.
Professor Murphy said screening was reliant on people self reporting.
He said the current number of confirmed cases was probably an underestimate, with confirmed cases in other parts of China, as well as Japan, Thailand and South Korea.
A report by London Imperial College's MRC Centre for Global Infectious Disease Analysis estimated that by January 12 there were 1,723 cases in Wuhan City with onset of related symptoms. Chinese health authorities have not commented directly on the report.
While the United States had already started screening for the virus at airports, Professor Murphy said Australia's response was proportionate.
What are coronavirus symptoms?
The virus' most common symptom is a high fever but Professor Murphy said measures like screening for temperatures had only been partially effective in the past.
"They missed a large number of cases," he said.
The virus causes a type of pneumonia and belongs to the same family of coronaviruses as SARS which killed nearly 800 people globally during the outbreak which began in 2002.
Symptoms include fever and difficulty in breathing, which are similar to many other respiratory diseases and pose complications for screening efforts.
The virus has an incubation period of one week, meaning people with the bug might not show symptoms over that period.
All the confirmed cases have been in adults and no children have been infected.
The virus is believed to be animal in origin having jumped from animals to humans, with Chinese authorities having linked initial cases to a fish market in Wuhan.
The health department was also working with the Department of Foreign Affairs and Trade to consider updating advice for Australians travelling to Wuhan ahead of Chinese New Year.
Hundreds of millions of Chinese tourists will be travelling domestically and abroad during the Lunar New Year holiday period that starts later this week.
With AAP
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