Here's what to do if you're feeling sick or have come in to close or casual contact with a coronavirus case.

Coronavirus: what to do if you've been exposed

NAB’s headquarters in Melbourne’s Docklands has been evacuated after an employee tested positive to COVID-19.

In a statement emailed to all employees today which is also posted to the banking giant’s website, chief executive Ross McEwan confirmed the alarming news that a worker on the ground floor at 700 Bourke Street had been struck down with coronavirus.

“In consultation with health authorities, we are vacating the 700 Bourke Street building and will have it pandemically cleansed,” Mr McEwan said.

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“All colleagues from 700 Bourke should go home and continue to work from home. We plan to have 700 Bourke Street ready for colleagues to return to work later this week.

“We will advise you as the situation becomes clearer.”

The banking boss said he and the executive leadership team were thinking of the affected worker and that they wished the individual a “speedy recovery”.

“The health and wellbeing of you and your immediate family is the most important thing. We understand you might be worried. If you have children in the Childcare Centre on Level 3 we understand that you will have been contacted by Little Stars at Southern Cross to collect your children,” the statement reads.

Ms McEwan said the health department was working through a “contact tracing exercise” to determine who might be at risk of contracting the virus and will speak with “at risk people” directly.

He stressed that people who were not contacted by the department had a “low” risk of infection, but that anyone deemed to be a “close contact” would be advised to remain at home for the isolation period.

“The safety and wellbeing of all our colleagues and customers is our priority. We understand you may be experiencing heightened stress during this event,” Mr McEwan said.

“We want you to know we are continuing to monitor the situation closely, keeping those who are affected in our thoughts, and are listening carefully to the questions and concerns we receive from you.”

Mr McEwan reiterated the importance of good hygiene practices in combating coronavirus and all illnesses, including regular handwashing, refraining from touching your face and remaining at home if you’re unwell as well as avoiding shaking hands.

He finished his message by thanking workers “for everything that you are doing to support each other and our customers”.

“We will get through this together,” he wrote.

There are currently 452 confirmed Australian cases of coronavirus and five people have died – one in WA, three in NSW and one in Queensland.

Last week, major corporate law firm King & Wood Mallesons abandoned its central Sydney office towers after revealing “at least one suspected case” of the deadly coronavirus came into contact with their network of employees, around 600 of which were sent home.

Westpac’s Sydney headquarters also sent home employees last week after three staff members were suspected of contracting the new coronavirus.

Another large law firm, Clayton Utz, triggered a shutdown of its Sydney office recently after a member of the team came into contact with the outbreak.