As new cases are confirmed across Australia, the government has sent a message to remain calm while it extends the travel ban to include South Korea.

The federal government has moved to reassure the public that it has things well in hand, with 53 confirmed COVID-19 cases in the country and two deaths.

The travel ban has now been extended to South Korea, as well as China and Iran, while travellers from Italy will be be subject to stringent checks.

In NSW, a Year 11 student is the latest person to test positive for the virus. Epping Boys high School has been shut on Friday and staff and students have been advised to self-quarantine at home.

The death of an elderly NSW woman in an aged care facility has also meant 17 children had to be tested after they visited the Dorothy Henderson Lodge at Sydney's Macquarie Park.

Group visits by children to nursing homes have been barred in NSW.

It has played out against a background of panic buying of sundries - and toilet paper in particular - at supermarkets.

The Northern Territory confirmed its first COVID-19 case, believed to be a NSW man who travelled to Singapore, on Thursday as Queensland recorded another two cases and 15 medical staff at Brisbane's Mater Hospital self-quarantined at home after coming into contact with an infected Chinese student.

Western Australia confirmed its third case and announced temporary precautions in Catholic churches that will result in holy water being removed and drinking from the chalice banned.

Tasmania in the meantime has opened a dedicated coronavirus clinic in the state's north, where a man tested positive to the virus earlier this week.

South Australian authorities confirmed on Thursday that a baby boy had contracted COVID-19 after his 40-year-old mother had tested positive to the illness.

Prime Minister Scott Morrison urged Australians to exercise common sense and to go about their lives and be alert, but not alarmed, about the virus.

But the public weren't the only ones under stress. The Australian Medical Association's president Dr Tony Bartone acknowledged the pressure and uncertainty many medical staff felt as they faced the coronavirus.

Following similar restrictions imposed on China and Iran, the government on Thursday announced foreign citizens in South Korea will not be allowed to enter Australia for 14 days.

Australian citizens and permanent residents returning from South Korea will be asked to self-isolate for 14 days when they return home.

Worldwide, the coronavirus has spread to 80 countries, with 95,000 confirmed cases and 3250 deaths.