“We need to wait until at least the weekend and early next week to see the impact of those harsher restrictions,” NSW Premier Gladys Berejiklian said on Wednesday.

COVID-19 cases spiked in the 24-hour period to 8pm on Tuesday with the state recording 110 new locally acquired cases – the third-highest daily tally – up from 78 the previous day.

But Berejilian said that figure would have been in the “thousands and thousands” had Greater Sydney and surrounding regions not gone into lockdown, which is now in its fourth week.

The virus must be quashed before restrictions can be lifted but the premier won’t be drawn on whether her government could go harder if daily case numbers don’t start to improve.

The lockdown is currently due to end on July 30.

Victoria would be facing a “world of hurt” in coming weeks if authorities had not immediately locked down the state, Chief Health Officer Brett Sutton says.

Twenty-two new local cases were reported in Victoria on Wednesday, the state’s highest daily total of the current outbreak.

It took the total number of active cases in the outbreak to 107, all of which have been linked.

But Sutton says he suspects the state would already be dealing with 200 to 300 cases if it had not entered lockdown a week ago, citing the highly infectious nature of the Delta variant.

“It is a variant that takes off from dozens to thousands of cases within just a matter of weeks,” he told reporters on Wednesday.

“If we’d locked down today, instead of when we did, we would get thousands of cases in the next couple of weeks. We’d be in a world of hurt … over coming weeks if we hadn’t done what we’ve done.”

Meanwhile, a nursing home in Sydney’s south is in lockdown after a nurse tested positive for COVID.

NSW Health says visitors or non-essential staff should not enter The Palms, in Kirrawee, and affected staff – some of whom are not vaccinated – have been isolated and will be tested within the next 24 hours.

“Thankfully, most of our residents are fully vaccinated against COVID-19,” the home said in a statement.

“We are treating all residents as close contacts of the affected staff member whilst we assess the situation in more detail.”

People in the central-western local government areas of Orange, Blayney and Cabonne have entered day two of a week-long lockdown after a COVID-19 positive delivery driver from Sydney visited the area and infected another person.

It’s the first time stay-at-home orders have been imposed in regional NSW and thousands of people in those towns spent Wednesday in long queues waiting to be tested.

NSW Police are running an operation to ensure compliance in the region, with high-visibility proactive patrols and compliance checks.

At least 60 of the new cases reported on Wednesday were circulating in the community for part or all of their infectious periods.

Most were in southwest Sydney and the government says that number has to fall to close to zero before it can consider lifting lockdown restrictions.

More than half – 56 – of the new cases are still under investigation and had not been linked to existing clusters so far.

The outbreak has prompted a change to the Higher School Education exam timetable, with face-to-face exams like dance and language speaking rescheduled to minimise disruption.

The NSW Education Standards Authority said it would not rush its decisions on the exam, with updates on dates for Drama and Music performance exams to come next week.

School students in Greater Sydney and other regions are in their second week of remote learning.