The Queensland government has raised the alert level under its traffic-light pandemic response to amber from green, telling people to be alert but not alarmed.

People are being advised to voluntarily wear masks in health facilities, indoors and on public transport, and make sure their vaccinations are up to date.

“We are entering another wave here in Queensland as in other states of Australia, and this is not unexpected,” Chief Health Officer John Gerrard told ABC radio on Friday.

So far, the bulk of cases linked to the new BQ.1 variant has occurred in northern Brisbane and on the Gold Coast.

NSW Premier Dominic Perrottet said NSW would not return to mandatory restrictions or isolating positive cases, but urged people to show caution if they were sick.

“We need to live alongside the virus. It’s not going away,” Mr Perrottet told reporters on Friday.

“We want people to be informed.

“My mantra is I want people to look out for each other.”

Victorian Deputy Premier Jacinta Allan also said there has been no change to health advice in the state, despite a 62 per cent uptick in cases over the past week.

But the government did say face masks remain a low-cost and highly effective tool to help reduce transmission.

“It is a timely reminder,” Ms Allen told reporters on Friday.

“Doesn’t matter whether you’ve got the cold, the flu or COVID it just makes sense to stay home if you’re sick.”

The Northern Territory is “strongly” encouraging, but no longer requiring, residents to get tested if they feel unwell. Face masks are still recommended in indoor settings.

University of South Australia biostatistics chair Professor Adrian Esterman said a mix of waning immunity and few public health measures was driving the new wave.

“Many people have had their last dose of vaccine over six months ago and by now have comparatively little protection against symptomatic disease,” Prof Esterman said.

“The onus is now on the other states and territories to follow Queensland’s lead and upgrade their health advice.”

Meanwhile, a cruise ship carrying thousands of people that potentially has hundreds of COVID-19 cases on board is heading to Sydney.

The Majestic Princess is due back on Saturday after a 12-day voyage around New Zealand.

Under the three-tier classification for cruises, COVID-19 is deemed to be having a “moderate impact” on the vessel’s staffing and resources, with three to 10 per cent of people infected.

With 4600 passengers and crew, that equates to between 138 and 455 positive cases.

“Cruising is a higher risk activity and cases of COVID-19 are expected on board cruise lines,” a NSW government spokesperson told AAP.

Princess Cruises said had strict and robust protocols in place.

“We continue to monitor closely some of the guests who tested positive to COVID-19 on board Majestic Princess,” a spokesperson told AAP.

“These guests are being cared for in their staterooms by our medical and support staff.”

WEEKLY VIRUS DATA BY JURISDICTION:

* NSW: 19,800 cases, 22 deaths

* Victoria: 16,636 cases, 41 deaths

* Qld: 5828 cases, 15 deaths

* SA: 6867 cases, seven deaths

* ACT: 1194 cases, 129 deaths

* NT: 369 cases, 79 deaths