A security guard who contracted coronavirus at a Sydney quarantine hotel has been fined twice by NSW Police for failing to isolate after his test.

The 22-year-old guard was tested after working at the Sydney Harbour Marriott, where another guard had earlier tested positive for the virus.

Police allege the man failed to self-isolate after he was swabbed.

A public health alert has been issued for Westfield Burwood and the nearby Service NSW centre, which the man visited after having his test.

Anyone who visited the Kmart and Woolworths there from 6.30-7pm on Thursday, August 20, or the Service NSW in Burwood from 2.30-3pm on Friday, August 21, is asked to monitor for coronavirus symptoms.

Health authorities in NSW confirmed three new coronavirus infections in the 24 hours to 8pm Sunday.

Two of those are in hotel quarantine, while the third was an employee at Liverpool Hospital who was a close contact of a previous case.

The guard is one of two from the Sydney Harbour Marriott to test positive to the virus.

NSW Police Deputy Commissioner Gary Worboys said he was “absolutely disappointed” by the security guard’s breaches of health protocol, saying the man should have known better.

“You have people working in high-risk locations that have induction processes and everyday are reminded about the seriousness of this,” he said.

“To have that person be told that they were positive to COVID and then to immediately go home and self-isolate and then not just on one occasion but on a second occasion not comply.

“The issuing of the tickets last night was an indication of how serious it was.”

NSW chief health officer Kerry Chant said the security guard who was fined was not particularly infectious.

“Further testing has indicated his level of infectiousness at that time was very low and it is unlikely we are going to be able to isolate any virus from his samples given that low level of infectiousness,” she said.

He was the second security guard to test positive after working at the Marriott.

Dr Chant said it was difficult to tell if the two infections were linked.

NSW reached a testing milestone on Sunday, with more than 2 million swabs taken since the start of the pandemic.

A total of 20,720 COVID-19 tests were completed in the 24 hours to 8:00pm yesterday, taking the state’s total to 2,016,293.

NSW Premier Gladys Berejiklian urged people in Sydney’s west or south-west to get tested if they have symptoms.

Those areas remain the main locations for new infections in NSW.