COVID-19 has seen several Australian state governments take the extraordinary step of barring entry to other Australians in a bid to stop the spread of the virus.
The closure of the NSW-Victoria border is the first time that’s happened in a century.
Prime Minister Scott Morrison has said throughout the pandemic that states should keep their borders open if possible, although softening his stance in light of the recent surge of cases in Victoria.
Mining billionaire Clive Palmer has claimed the WA Government would “destroy the lives of hundreds of thousands of people for decades” if it continued with hard border restrictions.
So where else have internal borders been closed, and has it worked? What lessons might Australia take from experiences elsewhere?
What does the World Health Organization say?
As the pandemic took hold in February, the World Health Organization (WHO) advised against the closure of even international borders, warning that restrictions could “have negative social and economic effects on the affected countries.”
But many experts disagree with this assessment.
Dr Norman Swan, host of the ABC’s Coronacast podcast, has said “our experience in Australia is different”.
“The key thing in this which we’ve been saying on Coronacast for a long time now is that you go in hard and you go in early, therefore I think it is probably quite reasonable that Queensland shuts its borders to people from Greater Sydney,” he said.
“You saw what happened with just a single man arriving in south-west Sydney from Victoria. That’s probably the source of most of what’s happened in New South Wales over the last couple of weeks.”
Acknowledging the reality of the situation, whereby most countries around the world have introduced border restrictions, the WHO this week released guidelines for governments seeking a gradual return to allowing international travel.
China, where the virus was first detected in Wuhan, was the first to impose significant internal border restrictions, cutting off the city and surrounding Hubei province from the rest of the country for two months starting in late January.
Authorities closed all transport into and out of Wuhan on January 23, with its 11 million residents ordered to stay home. All non-essential shops and businesses were forced shut.
This approach has been replicated time and time again throughout the epidemic, with Chinese authorities “ring-fencing” affected areas to contain the spread.
“The idea of ring-fencing has been around for a long time,” said UNSW epidemiology professor Marylouise McLaws, who told the ABC that Chinese authorities had likely learnt from the SARS outbreak of 2002-4.
Most recently, flights and trains in and out of the north-western Xinjiang Uyghur Autonomous Region have been cancelled due to a COVID-19 outbreak there.
Nevertheless, it took Chinese authorities more than weeks to order the shutdown of Wuhan after the coronavirus was first identified there in early January.
A study by researchers at the University of Southampton found that had these interventions been brought in three weeks earlier than they were, cases would have been reduced by a whopping 95 per cent.
Health Minister Ma Xiaowei acknowledged in June that China’s battle against COVID-19 had “exposed some problems and shortcomings”.
The United States
The response to coronavirus in the United States could not have been more different.
Even as President Donald Trump shut down travel between the US and Europe in March, as well as other parts of the world hard-hit by the virus, travel within the US itself has been largely unrestricted.
In the same month he closed borders to Europeans, Mr Trump floated the idea of forcibly quarantining the hotspot states of New York, New Jersey and Connecticut, yet later backed down.
Despite different states imposing drastically different social distancing and lockdown measures, state borders have not been closed.
Even with more than 150,000 deaths due to COVID-19, Americans have remained fairly free to travel domestically.
The US Centers for Disease Control and Prevention says on its website that “staying home is the best way to protect yourself and others from getting sick”.
It asks people who want to travel inside the country to consider a series of questions.
They include: “Is COVID-19 spreading where you’re going?” and “Is COVID-19 spreading in your community?”
But beyond an obvious warning there are no clear directions.
New York State says arrivals from states with “significant community spread of COVID-19” have to self-quarantine for two weeks. Most states, however, have no such rule.
A study published in April found that Americans were divided over the idea of “a travel ban between US states”.
A survey of 3,000 Americans found that around the same proportion strongly agreed with imposing border restrictions (38.5 per cent), as disagreed (37.7 per cent), compared with 23.9 per cent who neither agreed or disagreed.
“When trying to contain a pandemic, border closures are essential,” wrote one of the study’s authors, Sara Wallace Goodman, a political scientist at the University of California, Irvine.
The European Union
The EU implemented a 30-day ban on non-essential travel to the bloc for non-European citizens on March 17.
While the European Union is not a single country, its Schengen Area generally operates like one for the purposes of travel.
In normal times there are no passport or other border controls between the borders of 26 EU member states, with a common visa policy.
But COVID-19 has seen these rules largely thrown out the window, with many Schengen countries establishing border controls.
Denmark, Poland, Hungary and the Czech Republic — where governments were already anti-immigration — were among countries that closed their borders completely. Germany and Belgium banned all “non-essential” travel.
Professor Karin Leder is the head of the Infectious Disease Epidemiology Unit at Monash University’s School of Public Health and Preventive Medicine.
“A good way to think about whether international or domestic border closures make sense or not is to consider the gradient of risk of acquiring COVID-19 in different geographic regions,” she said.
“If people are travelling between two areas with similar COVID-19 incidence, then border closures are unlikely to offer any significant public health advantage, and will be associated with negative economic impacts.”
Italy and then Spain were devastated by the coronavirus early on.
The northern Lombardy region was forced into quarantine in early March, cutting some 16 million Italians off from the rest of the country.
Given some Australian states locked down around a month after this, “they may well have learned from Lombardy”, Professor McLaws, who is also a member of the WHO’s expert advisory panel on COVID-19, told the ABC.
The Schengen Area also includes Sweden, which resisted strict lockdown measures and has consequently had a drastically higher death rate than many other European countries.
South Korea was the site of an outbreak early on in the pandemic, with its citizens seeing international borders including Australia’s shut to them over fears of COVID-19.
But even as the world locked down, South Korea has not even closed its international borders, let alone domestic ones.
Doing this required aggressive testing and contact tracing that was influenced by South Korea’s experience of the MERS outbreak in 2015.
The country also implemented a sophisticated quarantining system the government calls ‘K-quarantine’.
“Korea has tried to remain as open as possible by responding proportionally to the risk assessments of experts instead of outright closing the border,” South Korea’s Consul General in Sydney, Sangwoo Hong, told the ABC.
“As a country that has endeavoured to keep our borders open and preserve the free movement of people during this pandemic, we hope our people-to-people exchanges across borders will soon become active and fulsome again,” he said.
“Eventually we’re going to have to think about opening up to [countries with] like-type epidemic spread — New Zealand, South Korea, and China, for example,” Professor McLaws of UNSW said.
There is therefore a need to “develop a good, a similar approach to pandemics, in order to have the ability to have trade, tourism and free travel between the regions,” she said.
“Closing borders works very effectively but it’s very difficult to keep borders closed while you’re waiting for a vaccine.”
“The data supports limiting mobility,” said Elina Ciptadi, co-founder of KawalCovid19, a website that has independently collated reliable data and information about Indonesia’s COVID-19 epidemic.
“Five million people exited Wuhan the night prior to the lockdown, spreading the virus to various parts of China and the world,” she said.
“Lombardy in Italy spread the virus throughout Europe all the way to Iran and New Zealand.
“The Tabligh Akbar [an Islamic event] in Petaling Jaya, Malaysia, I think caused 60 per cent of the infection in Malaysia and caused it to lockdown.
The most populous Indonesian island of Java has seen significant movement between its numerous provinces despite the efforts of authorities to discourage doing so.
Indonesia has the most cases of any country in South-East Asia, surpassing 100,000 this week. The capital Jakarta and East Java remain the country’s COVID-19 epicentres.
While testing rates across Indonesia have been among the lowest in the world, it is clear that Bali’s caseload is significantly smaller than neighbouring Java.
Some say this can be attributed to Bali shutting its borders to non-residents in April, and localised shutdowns of villages across the island.
But Balinese officials have made good on their pledge to reopen for tourism by July, allowing domestic tourists to start freely travelling there again this week.
Provincial authorities have said foreign tourists will be permitted to arrive from September 11.
“It’s impossible to close borders,” said Pandu Riono, a leading Indonesian epidemiologist and critic of the national Government’s handling of the crisis.
What lessons can Australia and the world take?
The Pew Research Centre found in April that 91 per cent of the world’s population, or 7.1 billion people, were living in countries where there were restrictions on people who weren’t residents or citizens arriving from overseas.
“Some countries, or some states or provinces within countries, have achieved elimination of community transmission, and in this context there are obvious benefits of closing borders — at least in the short term — to prevent entry of new infection sources,” Professor Leder of Monash University said.
“Given the fluctuating risks of COVID across time and place, the pros and cons of border closures is both highly context specific and dynamic.”
The WHO recommended this week that priority be given to “essential travel for emergencies”, travel of “essential personnel” such as public health workers, diplomats and seafarers, and repatriation.
“Sick travellers and persons at risk including elderly travellers and people with chronic diseases or underlying health conditions, should delay or avoid travelling internationally to and from areas with community transmission,” it said.
“I think it’s only reasonable to keep New South Wales and Victoria away from the other states, until they get their numbers down, close to elimination,” said Professor McLaws.
Additional reporting by Toby Mann and Ian Burrows.