Three cases in overseas travellers in hotel quarantine were also diagnosed, bringing the total number of cases in NSW to 4,158.
One locally acquired case is a household contact of a previously confirmed case linked to the Liverpool private clinic cluster, which now has a total of 12 cases.
The other locally acquired case is a close contact of a confirmed case linked to someone who attended the childcare centre at Oran Park.
There were 7,401 tests reported to 8pm on Thursday, compared with 6,952 in the previous 24 hours.
NSW Health has warned the state is "at a critical point, and the only way to find undiagnosed cases and prevent further transmission is to increase testing".
The department thanked the community of Oran Park community, where testing increased almost four-fold last week.
However, increases in surrounding suburbs were far more modest and NSW Health continued to appeal to the community in South Western Sydney to come forward for testing right away if anyone has even the mildest of symptoms like a runny nose or scratchy throat, cough, fever or other symptoms that could be COVID-19.
This is also particularly important in Western Sydney and South Eastern Sydney, the department said.