At her morning press conference on Sunday, Gladys Berejiklian stopped short of making any announcements of changes in restrictions given there were six locally acquired cases of COVID-19 in the 24 hours to 8pm last night.

Last week the Premier did foreshadow an announcement could be made this coming week regarding an easing in restrictions.

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All six new cases are close contacts of the western Sydney case in Berala reported on Saturday. Investigations into the source of the infection are continuing.

There were also three cases recorded in returned travellers, bringing the total number of COVID-19 cases in NSW since the beginning of the pandemic to 4,877.

There were 12,764 tests reported to 8pm last night, compared with the previous day's total of 14,574.

Ms Berejiklian and NSW Chief Health Officer Dr Kerry Chant renewed their calls for people to get tested if they are experiencing even the mildest of symptoms.

Ms Berejiklian said these new cases showed how easy it was for the virus to spread if one member in a household became infected and "demonstrates why we have those rules in place regarding households".

"Given we are towards the tail end of this particular outbreak, there haven't been other super seeding events and we want to keep it that way," she said.

"I can't stress enough the importance of people coming forward and getting tested.

"All of us want to see those restrictions we have in place eased.

"All of us want to be confident we can go back to what we had before Christmas.

"That will only be possible if we get those high rates of testing to give our health experts the confidence that we are on top of any unknown strains of the virus."

A staff member at Concord Repatriation General Hospital is one of today's new cases.

They are now in isolation but worked three shifts at the hospital in the cardiology and radiology wards while potentially infectious on January 12, 13 and 14.

The person's role involves minimal contact with patients and they wore a face mask during each shift.

Seven other staff have been identified as close contacts of this case. They are self-isolating and have all have tested negative for COVID-19 to date.

Staff who have been identified as casual contacts are being notified by the public health unit and are undergoing testing. There is no ongoing risk to staff or patients.

NSW Health last night issued public health alerts relating to new venues and some train services.

Anyone who went to the Wentworthville Medical and Dental Clinic at 122/128 Station Street, Wentworthville, and was in the dental, physio and imaging waiting room on Friday, January 15 between 11.30am and 1.15pm is a close contact who must immediately get tested and self-isolate for 14 days, regardless of the result.

People in other areas of the clinic at that time should monitor for symptoms and immediately isolate and get tested if they appear.

Anyone who was at Auburn Centrelink at 5-9 Macquarie Road, Auburn, on Thursday, January 14 between 3pm and 4.15pm should monitor for symptoms and if they appear, immediately get tested and isolate until a negative result is received.

Anyone who travelled on a number of T2 line train services between Warwick Farm and Auburn on Thursday January 14 and Friday 15 must also monitor for symptoms and if they appear, immediately get tested and isolate until a negative result is received. Details of service times are available on the NSW Government website.

People are urged to check the website for regularly updated details of venues of concern, and affected public transport routes, and are asked to follow the health advice provided.

The state's ongoing sewage surveillance program has detected fragments of the virus that causes COVID-19 at the treatment plant in Glenfield.

This catchment takes in the suburbs of Airds, Ambarvale, Appin, Bardia, Blair Athol, Blairmount, Bow Bowing, Bradbury, Campbelltown, Casula, Claymore, Currans Hill, Eagle Vale, Englorie Park, Eschol Park, Gilead, Glen Alpine, Glenfield, Gregory Hills, Holsworthy, Ingleburn, Kearns, Kentlyn, Leumeah, Long Point, Macquarie Fields, Macquarie Links, Menangle Park, Minto, Raby, Rosemeadow, Ruse, St Andrews, St Helens Park, Varroville and Woodbine.

Everyone in these areas is asked to be alert for symptoms, to get tested immediately if they appear and then isolate until they receive a negative result.

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