Six returned overseas passengers in hotel quarantine tested positive among 22,153 tests in the 24-hour reporting period, NSW Health said on Saturday.

Despite the positive news of no community transmission, mystery still surrounds a couple who contracted the virus this week.

There were fears a lockdown would be implemented over the Mother’s Day weekend after the couple in their 50s tested positive, with tracers unable to pinpoint how they became infected.

It is known a returned traveller in hotel quarantine somehow passed the virus on to the couple, but authorities are yet to identify the missing link between them.

The cases prompted the NSW government to introduce a raft of mandatory health restrictions including face masks in shopping centres and on public transport.

But Sydneysiders have been urged to continue going about their daily lives while taking heed of precautions.

The following rules are in force for Greater Sydney, Wollongong and the Blue Mountains until 12.01am on Monday.

*No more than 20 people allowed inside a home.

*No singing or dancing in indoor venues, including places of worship and entertainment venues (with the exception of weddings).

*Masks are compulsory at all indoor venues, including public transport.

*Only two visitors allowed per resident in aged care facilities.

*Drinking while standing up at indoor venues is not be allowed

In an attempt to stem potential outbreaks, NSW Health on Saturday issued an alert for anyone who visited the Double Bay Woolworths on Kiaora Road between 10.45am and 11am on Monday, May 3.

Anyone who visited the supermarket at that time is considered a casual contact and has been asked to get tested immediately and self isolate until they receive a negative result.