Residents and workers in four Sydney local government areas have been told to stay at home as NSW’s worrying COVID outbreak surged further on Friday.

NSW confirmed 22 more coronavirus cases on Friday, made up of five new infections and a further 17 that will be included in Saturday’s figures.

It is the biggest single-day rise in case numbers since the outbreak began just over a week ago.

There are now 65 infections in the Bondi cluster.

Without actually describing the tighter restrictions as a lockdown, Premier Gladys Berejiklian said people from Woolhara, Waverley, Randwick and the City of Sydney, and anyone who worked in those areas, would have to stay at home “unless absolutely necessary” for at least a week.

“This is in order for us to ensure that this doesn’t take a hold for weeks and weeks and we believe this is a proportionate response to the risk,” Ms Berejiklian said.

“We’ve done better than expected in terms of contact tracing and getting on top of all those links. But what this does is make sure that we haven’t missed any chains of community transmission.”

The rules come into effect at midnight Friday and will last for at least a week. They also apply to anyone who has worked in the four local government areas in the past two weeks.

“For example, I’m captured in that. I don’t live in those areas but I work there and have done so in the past fortnight, so therefore, I’m captured by that stay-at-home order,” Ms Berejiklian said.

Acceptable reasons to leave home are similar to those for lockdowns elsewhere in Australia throughout the pandemic. They are:

• For work and education, if it can’t be done from home;
• Exercise, in groups of up to 10;
• Providing essential care;
• Buying essential goods and services.

“Please don’t panic buy. No need for that. You can go out and buy anything you need any time of the day. We don’t have curfew, we don’t have anything like that,” Ms Berejiklian said.

In addition, the existing virus rules that apply across greater Sydney, Sydney, the Central Coast, Shellharbour, Blue Mountains and Wollongong, will also be extended until at least next Friday.

“Residents across greater Sydney should also limit unnecessary activity and avoid large gatherings in coming days and comply with the current restrictions,” Ms Berejiklian said.

Asked why she had avoided using the word “lockdown” in her announcement, the Premier said: “You can use whatever word you want.”

Tweet from @NSWHealth

Friday’s official update included 11 new cases – six announced on Thursday and five on Friday. All are linked to existing infections in the Bondi cluster.

Ms Berejiklian said authorities were particularly worried at transmission of the virus from workers to customers or clients.

“Many workers, unfortunately, who are face-to-face with a number of clients during the day have also been transmitting the virus,” she said.

“As we’ve said before, the mask is an important tool but even if you’re wearing a mask and you have the mildest of symptoms, you need to go and get tested, because otherwise, you could be transmitting the virus.”

Some of the venues of most concern for NSW authorities include the Joh Bailey hairdressing salon in Double Bay, SKIIN Medi Spa in Double Bay, the Fresh Nails salon at Westfield Bondi Junction, and the Life Cafe, Bondi.

Exposure alerts for the hairdressing salon and the spa, which share a building, have been extended to cover the entire period from June 15-23 for the salon and June 16-23 for the spa.

• For an updated list of NSW exposure sites and dates, click here

Chief health officer Kerry Chant said there had been workplace transmission at the salon. The exposure period takes in 900 clients, who are all in isolation.

“Because of the growing number of venues, the fact that we’ve had confirmed transmission at a number of the venues, we need to reduce people’s movements,” she said.

“The rationale for including the stay-at-home order to follow the workers is because we know that many of the workers do live outside those geographical [council areas], so we want them to follow those stay-at-home orders, so again, we don’t establish seeding in western Sydney and south-western Sydney.”

Dr Chant warned coronavirus case numbers would continue to increase, even with the stay-at-home orders. Infections are particularly expected in household contacts.

“I expect the numbers to be high, as I’ve said this morning – it’s 17,” she said.

“The first thing that I will ask my team is – how many of those cases were already in isolation? And therefore posing no ongoing risk.

“Our contact tracers are getting on top of the venues very quickly, but we’re still seeing some people who are infectious in community for a period of time. And this will allow us, it’s almost a circuit breaker, to give us that time.”

NSW Police will also step up enforcement of virus rules for the next week.