New South Wales has recorded 24 new local cases of COVID-19, half of which were in the community while infectious.
Premier Gladys Berejiklian said it was "a cause for concern" it appeared some essential workers were leaving their houses with symptoms or going to work and passing the virus onto others amid the 14-day lockdown in Greater Sydney.
"We can't afford to have people continue to have the virus going about their business," she told reporters on Thursday.
On Wednesday, it was revealed , sending more than 100 patients and staff into isolation.
One of the nurse's household contacts and a friend have now also tested positive.
One of those contacts is also a healthcare worker who worked in the Fairfield and Royal North Shore hospitals.
Another close contact of the 24-year-old is an aged care worker at a SummitCare facility in Sydney's Baulkham Hills, who is understood to be unvaccinated.
SummitCare confirmed the positive case in a statement, saying no other workers nor residents have tested positive to date, and that residents and staff in contact with the infected worker will be tested daily.
"We are committed to ensuring our staff and residents are virus-safe and are working with industry experts and government stakeholders to ensure we continue to achieve this goal," the facility said on Thursday.
NSW Chief Health Officer Kerry Chant said almost all of the 149 residents at the Baulkham Hills facility had been fully vaccinated.
Seventeen of the new cases announced on Thursday are linked to previously confirmed cases, with 11 of these linked cases being household contacts.
Seven new cases reported remain under investigation. The Bondi cluster at the centre of Sydney's outbreak now sits at 175 cases.
NSW Health has also issued for numerous bus and train routes as well as more than 20 venues in Sydney's east, south and west.
Later on Thursday, authorities with the Sydney Local Health District said the vaccination centre at Sydney Olympic Park was attended by a person who tested positive on Wednesday.
The person was at the centre on Tuesday, 29 June between 3:30 and 5pm. It has been thoroughly cleaned and NSW Health is contacting casual and close contacts, SLHD chief executive Dr Teresa Anderson said in a statement.
"The vaccination centre remains open and people are encouraged to continue to come forward for their vaccination appointment if they are well. You must not attend if you have any symptoms, however mild."
Anyone who has been advised they are a close contact must not attend, while casual contacts must return a negative test before their visit.
Ms Berejiklian also announced that mass COVID-19 vaccination hubs would be established in Wollongong and Macquarie Fields as well as another clinic in Sydney's CBD, while another hub in the Hunter regions was already underway.
With AAP.
