One of the strategies for keeping international travel afloat during the pandemic was the creation of ‘travel bubbles’: alliances between neighbouring nations with low infection rates that would allow travellers from those countries to freely visit. But as the summer draws to a close and infections continue to pop up, it appears that, in many places, the travel bubble has burst. There was a lot riding on the alliances. The pause on international tourism doesn’t just spoil family vacations; it affects the global economy in profound ways, too. The World Travel and Tourism Council estimates that about one in 10 jobs are related to tourism and travel. For popular destinations like Greece, where the tourism sector is responsible for about 40 per cent of jobs, the effect is even more significant.

In May, New Zealand and Australia garnered attention when they announced a plan to create one of the first travel partnerships during the pandemic. The “Trans-Tasman bubble” would allow citizens of each country to travel to the other without a quarantine or a test. The hope was to enact it by early September, but in early August, a coronavirus outbreak in the Australian state of Victoria put those plans on hold.

For a while, Europe seemed to represent the best hope for getting tourism going, and it began with the bubble concept. On May 15, the Baltic States of Latvia, Estonia and Lithuania created the first travel bubble in Europe; later that month, Hungary and Slovenia agreed that their citizens could continue to travel between the two countries. Soon, much of Europe became a giant bubble. The European Commission created “Re-open EU,” a site listing travel rules within European countries. Each member country began easing restrictions at its own pace. Italy and Germany for example, opened quickly to travelers arriving from inside the European Union or the border-free Schengen zone. Britain also began opening up to its neighbours.

The welcome mat wasn’t rolled out long, though. Flare-ups of the virus caused borders to shut on short notice, disrupting travelers’ plans. In late July, Britain abruptly announced that travelers returning from Spain would have to self-quarantine for 14 days, just a few weeks after it had opened restriction-free travel to the country. In mid-August, British vacationers in France had to either rush home to beat newly announced restrictions, or face two weeks of quarantine when they returned.

Asia, too, has had its burst travel bubbles. Thailand had hoped to invite travellers from nearby countries with low virus rates, such as Japan, Hong Kong and South Korea, to visit without requiring self-quarantines on arrival. New waves of the virus cancelled those plans.

While some countries jointly announced agreed-upon travel bubbles with neighbours, others created de facto ones by publishing lists of which nearby countries’ residents were allowed in and under what circumstances. In the United States, which accounts for about 25 percent of the world’s cases, some states like New York, New Jersey and Connecticut have created their own de facto bubbles, stipulating that travellers coming from a long list of states with a seven-day rolling average of positive tests greater than 10 per cent, or number of positive cases over 10 per 100,000 residents, self-isolate on arrival for 14 days.

The idea of bubbles created between neighbouring countries has given way in recent months to “travel corridors” and safe lists, sets of countries and territories around the world whose residents, depending on their destinations, don’t have to self-isolate, unless they are showing symptoms of the virus or have recently been exposed. These travel regulations are posted on government websites, such as Re-Open EU and the Centers for Disease Control website, and change as new information is received. For example, as of Aug 21 at midnight, travellers arriving in Norway from newly named “red” status places, including Austria, Greece, Ireland and Britain, were required to go into quarantine. Britain’s website, which lists more than 60 countries and territories from which travelers can visit without self-isolating, removed Croatia and Austria from that list last week and added Portugal. Belgium’s foreign affairs website updates the list of restrictions for travellers from various countries each day at 4 pm.

The sites also list countries’ virus-testing requirements for travellers. Some nations recommend arriving with evidence of a negative result and offer tests at the airport or 14-day self-quarantines as an alternative. Others, like the United States, which recently dropped its advice that newly arrived travellers quarantine for two weeks, don’t require testing to enter the country.

Rather than prohibit all travellers from higher risk countries, Greece recently began requiring that people entering from a specified list of locations arrive with a negative test result for COVID-19, performed within three days of their entry.

The risk is high both for travellers and the countries they are visiting, said Dr Brad Connor, the New York City site director for the GeoSentinel emerging infectious disease surveillance network of the CDC and a long-time travel medicine and infectious disease specialist. Asymptomatic and pre-symptomatic travellers carrying the virus can inadvertently bring it into an area undetected and cause an outbreak for which there is no vaccine and no reliable treatment, Dr Connor said. “We all want to travel again in a safe way,” he said. “Unfortunately, the approaches so far have not worked.”

Infection waves can be local and some countries’ restrictions get down to regional specifications. Belgium’s list recommends testing and quarantine for travellers arriving from certain areas within other European Union countries, like the southwest regions of Bulgaria. Norway declared that the region of Norrbotten in Sweden, which has fewer COVID cases than most other areas in the country, will be changed on its list from “red” to “yellow,” and anyone entering Norway from there will not be required to go into quarantine.

Cordoning off an area of the country for international tourists is the latest idea aimed at preserving a portion of this year’s tourism revenues. Thailand is considering a new programme where international travellers who are willing to stay for 30 days are allowed into Phuket, where they will quarantine in specified resorts and undergo two COVID-19 tests.

The island of Anguilla in the Caribbean, which said it had no current virus cases, recently announced it would begin welcoming travelers who must apply to visit, giving preference to those from countries with lower infection rates and those who plan an extended stay. Travellers must arrive with evidence of a recent test showing they do not carry the virus. They will also need to quarantine for 10 to 14 days when they arrive, undergo two more virus tests and pay a fee for these services. The web portal states that “Anguilla is open for approved visitors from certain countries.”