A man in his 50s was confirmed to have tested positive on Wednesday - on Thursday, authorities confirmed his wife had tested positive.
Thousands of people across Sydney remain on high alert with the list of venues visited by the infectious COVID-19 cases growing further each day.
Singing and dancing at indoor venues, with the exception of weddings, will also be outlawed for the next three days.
A Sydney man has tested positive for COVID-19, in what appears to be a case of community transmission.
Chief Health Officer Dr Kerry Chant said genomic testing linked the latest cases with a returned traveller from the United States at a Darling Harbour quarantine facility.
"We can't find any direct link between our case, so what we're concerned about is there is another person that is as yet unidentified that infected our case", Chant said.
A report in the Sydney Morning Herald newspaper on Thursday, citing unidentified sources, said at least two repatriation flights will be dispatched to India every week from the middle of this month to bring home around 9,000 Australians. "We need to be aware that virus is still around".
Earlier on Thursday, it was revealed NSW Treasurer Dominic Perrottet has been forced into self-isolation after he attended the same CBD restaurant as the man on Friday.
Fragments of the virus that causes Covid-19 have been found in the Marrickville sewerage network.
Players and staff from both Sydney AFL clubs and the NRL's Sydney Roosters are also undergoing testing after the positive case visited Sydney's Moore Park.