The update comes after a woman aged in her 50s and a household contact of hers, a woman aged in her 20s, were officially diagnosed overnight.

Health authorities have also updated the testing advice for those who attended two Greek Orthodox churches.

Read more: Live coverage: Wollongong's newest COVID case as it happens

The new advice for St Nektarios Greek Orthodox Church located at 39 Atchison Street, Wollongong, is that anyone who attended on Sunday, December 27 between 9am and 10.15am is a close contact and must get tested and isolate for 14 days regardless of the result.

Anyone who attended the Holy Cross Greek Orthodox Church at 18 Stewart St, Wollongong on Sunday, December 27, between 10.30am and 11am is now considered a casual contact who must get tested and isolate until a negative result is received.

This replaces previous advice that anyone who attended either church should get tested immediately and self-isolate until they receive further advice from NSW Health.

People who were at the Coffee Club at Stockland Shellharbour, located at 211 Lake Entrance Road on Sunday, December 27, between 11am-12pm is considered a casual contact and must get tested immediately and isolate until a negative result is received.

People should also monitor for symptoms and get tested immediately and isolate if they appear, if they visited Myer at Stockland Shellharbour on Sunday, December 27, between 12pm-12.40pm

Also those who visited Coles at Figtree Grove Shopping Centre on Monday, December 28, between 4.45pm-5.20pm should monitor for symptoms and get tested immediately and isolate if they appear.

This is the same advice for people who visited all of Figtree Grove Shopping Centre, except for Proust Optical, at various times.

As reported earlier on Wednesday, NSW Health authorities have advised anyone who attended the following venues at the listed times to monitor for symptoms and get tested if they appear.

This supersedes previous advice to get tested immediately and isolate until a negative result is received.

The venues include Wollongong Central on Crown Street on Wednesday, December 23, between 3.30pm-4pm.

It also includes Figtree Grove Shopping Centre on the Princes Highway on Monday, December 21 between 12.30pm-1.30pm; Wednesday, December 23 between 8.45am-9am and Thursday, December 24 between 6.45am-9.30am.

NSW Health advises anyone who attended Proust Optical Figtree, which is located inside Figtree Grove, on Monday, December 21 between 9:30am and 5pm and Wednesday, December 23 between 9:30am and 2pm is a casual contact and must get tested and self-isolate until they receive a negative result.

They should continue to monitor for symptoms and if any symptoms occur, get tested again.

Close contacts from this venue will be contacted by NSW Health.

Additionally, NSW Health is asking people who attended the following locations to be tested immediately and isolate until they receive a negative result as part of investigations into the source of the case from Wollongong.

Buckley's restaurant and bar on Opera House Promenade in Sydney on Thursday, December 17 between 7.30pm-9pm for indoor diners and staff only.

Also the Open Air Cinema screening of Prom at Lady Macquarie's Chair in Sydney on Thursday, December 17.

NSW Health urges anyone in NSW with even the mildest symptoms, such as headache, fatigue, cough, sore throat to get tested.

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