States and health experts are pleading for tougher rules to seal shut international borders and protect Australia against a worrying new strain of COVID in the United Kingdom.

Leaders fear the mutated virus could exploit weak points in Australia’s quarantine system.

The Victorian government wants new rules to stop the new, highly infectious B117 strain from entering the country, including stringent pre-flight testing for overseas arrivals and potentially locking the border to passengers from the UK.

Virus numbers in the UK have exploded in recent weeks, more than doubling from 27,000 daily cases in mid-December to 58,000 on Monday. This prompted another nationwide lockdown.

Researchers are still studying the newly-emerged strain, known as B117.

It is not believed to be any more deadly than the prevalent strains, but experts think it could be between 40 and 70 per cent more transmissible.

British PM Boris Johnson announced a new national lockdown. Photo: AAP

“The United Kingdom is disintegrating,” University of NSW adjunct professor and infectious disease expert Bill Bowtell told The New Daily.

“The new caseload is like a rocket taking off … everything is going wrong at once.”

Several cases of the new strain have been detected in Australia’s hotel quarantine program for returning international travellers, including three in Perth on Tuesday, and five in Victoria.

Nations including Hong Kong, France, Germany, Ireland and Italy had placed restrictions or bans on UK flights in the face of the new variant, and those calls have now been made in Australia.

Victoria’s Police Minister Lisa Neville said the state’s deputy chief health officer would raise concerns about the UK strain at a health ministers’ meeting on Tuesday.

“(Our) job is to make sure that our hotel quarantine system is as robust and strong as possible, that this does not get out, whether it’s the UK strain or any other strain,” Ms Neville said.

The Herald Sun newspaper reported Victorian officials wanted an urgent meeting of the national cabinet – not due to meet until February – to discuss testing UK arrivals before they board planes.

WA Premier Mark McGowan agreed, calling the testing plan a “no-brainer”.

VIC police minister Lisa Neville. Photo: AAP

Prime Minister Scott Morrison said he had not had a request from Victorian Premier Daniel Andrews about a cabinet meeting, but that federal health officials were considering options.

“I would have no hesitation and probably wouldn’t even require a national cabinet meeting to action that advice,” the PM told Melbourne’s 3AW radio.

“I suspect we could action it even without [national cabinet].”

Experts want tougher border rules

Professor Bowtell, an architect of Australia’s HIV response, backed the calls for pre-flight testing of international arrivals.

He said anyone with a positive response should be blocked from getting on a plane to Australia.

“The Australian borders have to be as hard as the borders between states,” Professor Bowtell said.

“We must understand what we are facing. The present situation in NSW, and by extension Victoria, has come about through too many exemptions to quarantine arrangements at airports.”

No further exemptions from hotel quarantine for at least UK arrivals. Increased, upgraded quarantine capacity to handle safely increased number of 2021 arrivals. Australians demand 0/0 and hard border. @Politics_SMHAGE @7NewsAustralia @9NewsAUS @SBSNews @abcnews @SenatorWong

— Bill Bowtell AO (@billbowtell) January 4, 2021

Professor Bowtell called it “crazy” for flight crew to not be subject to tighter virus controls.

“Infections in Sydney and Victoria are linked to flight crews. There’s no occupation that gives you exemption from infection. This is crazy,” he said.

“The failure is at quarantine. People are coming in who aren’t being properly tested.”

Ms Neville said Victoria was testing all flight crew, as well as workers in hotel quarantine each day. She urged other states to follow suit.

Associate Professor Hassan Vally, an epidemiologist at La Trobe University, said Australia should do “anything we can” to prevent COVID from entering the country.

Experts want more rules on airport arrivals. Photo: AAP

However, as he noted experts were still analysing the exact characteristics of the new UK strain, he said radical changes to current health arrangements may not be needed.

“It seems to be more efficient in being transmitted from one person to another. The question is, ‘Is it a game changer? Does it change everything we’ve been doing? For me, no,” Professor Vally told TND.

“It might be a reminder of how hard we have to work to control transmission. We should be taking the current strain incredibly seriously. If we have a strain that’s a bit more transmissible, that doesn’t change anything as far as I’m concerned.”

He said a virus mutating to a new strain was “natural”, but said current health measures should be adhered to.

“We should already be doing everything we can to stop the virus. It’s not something that changes the landscape completely,” Professor Vally said.

“The recent epidemiology is showing hotel quarantine is a weak point … it’s not a difficult thing to do, to test people before they come.”

Bill Bowtell says too many exemptions are being granted from hotel quarantine. Photo: AAP

But leading epidemiologist Professor Peter Collignon, an infectious disease expert at the Australian National University, urged caution.

He said banning British arrivals from Australia was “probably too stringent”.

“Having constraints like not letting anybody from the UK come back to Australia, I don’t think is reasonable at this period of time,” he told Sky News.

“For UK residents returning and everybody else, we need to make sure we have infection control and prevention as good as possible in our quarantine hotels, to minimise the risk of any escaping into the community.”

Professor Collignon said “we don’t have all the answers” on the UK strain and suggested part of the spike in new cases could be due to Christmas holidays and travel.

He said testing passengers before they boarded flights was “practicable and worth doing”, but said measures would need to be put in place to support people who were turned away at terminal gates.