The coronavirus spike sweeping Melbourne has put the reopening of Queensland’s borders in jeopardy after 16 new cases were reported on Monday.

NSW also signalled it might impose restrictions on its southern neighbour after more than a week of double-digit increases in Victoria that have authorities worried about a second wave of the deadly virus.

“We do issue that travel warning and recommend people not travel to those hot spots that have been identified by the Victorian government,” NSW Premier Gladys Berejiklian said on Monday.

State Health Minister Jenny Mikakos said six of the new cases were linked to known outbreaks, four were in hotel quarantine, five detected through routine testing, and one was being investigated.

Victoria now has 222 cases believed to be related to community transmission, with the state government focusing its efforts on particular suburbs.

Among the new cases, two are linked to staff at an H&M shop at Northland Shopping Centre in Melbourne’s north, taking that cluster to four. There is also a toddler at the Great Beginnings Nursery in Reservoir and two teachers at schools in Caroline Springs.

The state has 1847 confirmed cases of COVID-19 after five were removed due to duplication. That made a net increase of 11 on Monday.

On Sunday night, the Australian Health Protection Principal Committee called for Victorians to avoid six virus hotspots in Melbourne and for residents who live in them not to leave their suburbs.

They are the cities of Hume, Casey, Brimbank, Moreland, Cardinia and Darebin – which together are home to more than a million people.

The AHPPC said 83 per cent of new coronavirus cases in Australia in the past week were in Victoria.

Ms Mikakos said the state government was concerned about the new cases, advising against interstate travel for people from the hotspots.

“We have not issued stay-at-home directions for those hotspot areas, but, of course, we don’t rule anything out. We are very concerned about the level of transmission in those particular locations,” she said.

“We know that some areas in our community have had higher case numbers in recent weeks, and that has particularly been spread through family scenarios, extended family members coming together, visiting each other and spreading the virus across their family members, but also the risk there is that the family members can transmit that virus to workplaces, to school settings, and other locations.”

Ms Mikakos said there would be widespread testing at Keilor Downs Secondary College and Albanvale Primary School, both in Melbournbe’s north-west. Students will be tested regardless of whether they have symptoms.

There will also be pop-up clinics in Keilor Downs, Sunshine and Dandenong and extended opening hours at the Deer Park drive-through site. “Roving testing squads” will door-knock in Cardinia and Brimbank.

“We do have community transmission still in Victoria – people should get tested even if they have very, very mild symptoms,” Ms Mikakos said.

The Melbourne areas of concern – and the new cases each has recorded this month. Photo: ABC News

Tourism and hospitality sectors hit again

Meanwhile, Cardinia Mayor Jeff Springfield said he found out about the travel advice for his region only when he was contacted by media on Sunday night.

“We haven’t received any further information at this point beyond the announcement from the AHPCC,” Mr Springfield told 3AW Radio on Monday.

The move to effectively prohibit residents from travelling to and from the council areas has caused further distress for the already struggling hospitality and tourism sectors. Hundreds of businesses had been planning to increase patronage from 20 to 50 people from Monday but that is now on hold.

Restaurant and Catering Industry Association CEO Wes Lambert said the decision was taken without consultation.

He also said cancelling reopening plans would affect supply chains and employees who were scheduled to return to work on Monday.

“It certainly was a knee-jerk reaction to a situation that has happened in family clusters,” he told Nine’s Today.

“They only had 34 hours notice. That’s really not enough time to make an effort to get all of that cancelled.”

Queensland had no new cases of COVID-19 overnight, while NSW recorded had two.

NSW Health said a man, aged in his 30s, tested positive to COVID-19 and was isolating at home. It was unclear as to how he contracted the virus. The other case was a return traveller.

Meanwhile on Monday, NSW Deputy Premier John Barilaro said the state government would discuss “managing” the number of people coming in from Victoria.

Mr Barilaro said the looming school holidays and the start of the ski season on Monday could lead to a surge in travel between NSW and Victoria.

“We’re trying to get out of the COVID crisis, we’re lifting restrictions and now there’s a real threat from Victoria,” he told Channel Seven.

Any restrictions could also pose major headaches for border population centres, such as Albury-Wodonga.

A driver is stopped on the Queensland border in April. The state’s borders remain shut. Photo: Getty

Queensland Premier Annastacia Palaszczuk said her government might consider opening its border only to selected states.

But, it would make no formal decisions ahead of Friday’s national cabinet meeting.

Queensland has flagged the second week of July as a possible border reopening date.

The Victorian surge prompted Queensland’s chief health officer Dr Jeannette Young to designate all of greater Melbourne’s 31 local government areas plus five in the surrounding region as virus hotspots.

South Australian Health Minister Stephen Wade has indicated he might backtrack on plans to open the Victoria border on July 20.

“If the situation doesn’t change, the borders are not opening,” he said.

“We are not going to open our borders to Victoria unless it’s safe to do so.

“To have a five-fold increase in community transmission is worrying for Victorians, it’s worrying for the whole nation.”

-with agencies