A doctor who contracted coronavirus in one of the first cases of person-to-person transmission in Australia is in a stable condition and "going quite well", the NSW government says.
Health Minister Brad Hazzard said it still wasn't clear if the man had infected others after becoming contagious.
NSW Health Ministry and the local health districts are busy talking to various people he might have come into contact with.
"We are making sure we get in contact with them and make sure they don't have symptoms," the minister told Nine's Today program on Tuesday.
"It's a bit of a worry."
NSW has now had nine confirmed cases of COVID-19, with five being diagnosed in the past week. The latest three were confirmed on Monday. The other four have recovered.
Two of those cases include the doctor, 50, and the 41-year-old sister of an infected man who had recently returned from Iran where the virus is rampant. Both were person-to-person transmissions outside of China, where the outbreak began.
The doctor had not recently been overseas leading experts to conclude he may have contracted the virus while working in a clinical environment or while in the community, although it was not yet clear which.
NSW Chief Health Officer Kerry Chant said the case of the health worker raised the question: "Was there a case that was missed?"
"Our key focus at the moment is to contact staff or patients that may have been close contacts of this gentleman," she said on Monday.
The third new case in NSW is a 31-year-old man who flew into Sydney on Saturday from Iran and developed symptoms 24 hours later
Mr Hazzard on Tuesday again cautioned NSW residents to be cautious and make sure they wash their hand regularly, not shake hands and to sneeze into their elbow if a tissue wasn't available.
"Perhaps it is time to forget handshaking at the moment because that's a very easy way to transmit the virus," he added.
"If you are out and about and you put your hand on a banister on a train or railway or bus, it is possible you end up with the virus on your hands."
Asked about cases of people stockpiling non-perishable goods and toilet paper, Mr Hazzard said everyone should remain calm.
"I think we should be very cautious, washing our hands, but not rushing out and buying up," he said.
The state government is also warning of a likely convergence of a COVID-19 pandemic with the annual winter flu season and announced a lowering of the age at which pharmacists could administer flu jabs to 10.
