(Bloomberg) -- The coronavirus pandemic has sent shock waves through the global travel industry and the economies most reliant on tourism. Now, with vaccines rolling out, governments are looking to strike a balance between the continuing fight against Covid-19 and allowing travel to resume. I asked Greek Tourism Minister Harry Theoharis, Gloria Guevara, chief executive officer of the industry group World Travel and Tourism Council [WTTC], and Sarah Pitt, a virologist at the University of Brighton in the U.K., about the road ahead.

Stephanie Baker: Minister Theoharis, there’s been lots of talk about vaccine passports opening up travel this summer and possibly even earlier. You’ve got an agreement with Israel to allow the vaccinated to travel freely between both countries. Will you require vaccination from travelers from other countries and, if so, when?

Harry Theoharis: Greece has been a leader in vaccination passports to enable less restrictive traveling. We anticipate that by this summer, people who have been vaccinated will be able to travel without restrictive quarantine measures or the need to provide negative test results. People who have not been vaccinated will still be allowed to travel, but they will be required to provide a negative test result. We have two new weapons in our arsenal, namely the vaccination programs and rapid tests. The latter are cost-effective, quite reliable, and quick.

Baker: Gloria, there’s a widespread expectation that we’ll need documentation of either vaccination or test results in order to travel. But we know that, for instance, the World Health Organization [WHO] yellow-fever certificate has been plagued by forgeries. Countries like the U.K. and the U.S. are giving people small paper cards after vaccination. How will this work? Will there be a global health pass or will we be dealing with competing apps on our phones?

Gloria Guevara: The WHO opposed health passports, so we are completely aligned with them. WTTC is not in favor of the yellow-fever certificates of health passports. Health passports can contain all of your information, such as every single vaccination taken throughout an individual’s life and any health conditions they might have, so there are some data-privacy concerns.

However, WTTC is in favor of health passes. There is an important distinction to make between the two. We need to make the invisible visible and identify the infected individuals, and the only way to do this is through mass testing. Testing is the solution. You can do a test before traveling and the results can be included in a digital pass that can be shown to the airline, hotels and through different points in your journey.

Once someone has been vaccinated, that vaccination has to be included in the digital certificate. However, based on the data that we have received from the WHO and medical experts from multiple countries, we cannot guarantee that once someone has been vaccinated they will not be able to transmit the virus. Therefore, for a period of time we may need to still administer tests to everyone, including vaccinated individuals.

Baker: Sarah, we still only have limited information about how much vaccines stop transmission. Until more data come, can we really use vaccination certificates as the key to unlock travel? Or do you think testing will still be mandatory and, if so, for how long?

Sarah Pitt: We do have some early results about how well the vaccines work “in the real world” coming out of countries that started their vaccination programs in December 2020 and January 2021. So far it looks as though the vaccine definitely reduces the chances of a person being seriously ill and hospitalized from Covid-19 infection. But some studies I have seen show transmission of the virus could still occur. So while the virus is still being transmitted at high rates in many countries, yes, testing will be really important.

Also, many countries are prioritizing vaccination of the older age groups and those most at risk from serious Covid-19 disease and those at high risk of catching the virus (e.g. health-care workers). So younger workers, say a 30-year-old who works in an office, may not get their first dose of the vaccine until late summer. This will be a problem for them if evidence of vaccination is needed for travel.

Baker: Minister, will you be making agreements with other countries? If so, which ones are you talking to? If I’m living in the U.K., when is the earliest I might be able to travel to Greece?

Theoharis: We feel that the agreements like the one with Israel are the way forward. They can serve as a template for the gradual, safe reopening of tourism. The U.K., U.S., Russia, Serbia and Ukraine are among the countries we are in technical discussions with. Of course we hope the European Union can work together as one and remove the need for bilateral discussions and agreements.

Testing is here to stay

Baker: Gloria, if testing is to remain an enduring feature of travel—akin to the no-liquids rule on planes—are short city breaks a thing of the past given the cost of testing and possible quarantine?

Guevara: Short city breaks will continue, because the sector is proposing to implement testing before departure with a low-cost, high-efficacy test. So a test with $10 maximum per individual should be fine to isolate the people infected and apply before departure. In conjunction, following protocols like wearing masks, sanitization and all the things that we know will help us reduce the risk to the maximum and resume international mobility.

Baker: Greece welcomed back visitors last summer, offering useful lessons for other countries wanting to reopen. Tell us what you learned and what measures you’re taking to keep tourists safe this year.

Theoharis: We need to constantly monitor the situation and act appropriately. Border testing is essential for the safe reopening. We installed an artificial intelligence system to target our testing. It was fed by passenger locator form [PLF] data (we mandated digital filing of the PLFs), public epidemiological data per country and results from our own testing at the border. We managed to double the effectiveness of our limited testing resources, to get advanced warning for the worsening situation of a specific country seven to 10 days in advance of the public data. As a result, we were very successful in safeguarding our population. Finally, it’s very important for the private sector to implement health and safety procedures with vigilance.

Baker: There’s still considerable nervousness around flying. Some people say it would be safer if airlines leave the middle seats open. Gloria, does that make a difference? What’s the evidence for the claim that flying is safe?

Guevara: First of all, the best protection that you can have during your flight is wearing a mask. Secondly, according to plane makers, aircraft have filters where the air is filtered every three minutes, which is equivalent to what happens in a hospital operating room. The best protection that you can have is wearing a mask and using hand sanitizers.

Baker: Sarah, the U.K. ban on international travel will stay in place until May 17, but the government said it will review the rules in mid-April. What steps should the U.K. take to balance public-health priorities with the needs of an industry that’s been shut down for a year?

Pitt: We really need to proceed with extreme caution. I think the government should err on the side of compensating travel and tourism businesses for loss of income, to protect public health during summer. Then we can use the lower rates of transmission that we expect in the summer to really get the virus under control.

Flying with children

Baker: The approved vaccines have not been tested in children under 16. Can all three of you tell us how countries will likely treat families when the parents are vaccinated but the children are not? Will they simply be tested, and from what age?

Theoharis: Our current rules state that testing is required from 12 years old upwards. We will most likely continue to follow that rule, although no firm decision has been made as of yet.

Guevara: The global private sector is totally against vaccination as a requirement to travel because this can drive the wrong behavior and create two tiers of citizens. Currently the supply is limited, and there are a lot of developing countries that don’t even have a vaccination calendar. We believe it will take years to get 7 billion people on this planet vaccinated, and still testing needs to be done for children under 16. Vaccination is not the only solution. Testing will be included as part of the travel experience.

Pitt: We know that young children are less likely to be ill with Covid-19, but we think they can transmit the virus. Older children and teenagers can get ill and transmit the virus. So if the plan is to test children, it should include younger children (5 years old and above).

Baker: Gloria, many countries are eager to welcome back tourists to kickstart their economies. Which countries besides Greece have been successful at preparing for tourism in the age of Covid? And given that the EU has been slow to roll out vaccines, will it be safe to take a holiday in Europe this year?

Guevara: There are multiple countries that have done a good job providing certainty and clear rules for travelers, which is the base for a successful reopening for tourism, such as Greece. Iceland has clear rules, as well as many countries within the EU and some countries in Asia and in the Americas. Follow the protocols and expect rapid testing as part of your experience. Spain, France, Portugal, Italy and Germany as examples have been defining these clear rules and will make announcements very soon.

International travel corridors

Baker: Sarah, should people be thinking of choosing a destination that has very little Covid or has an advanced vaccination program? There are some tourist destinations with zero, or negligible, Covid cases. I’m thinking the Bahamas or Mauritius. And the U.S. vaccine rollout is gaining steam. But Europe looks like it will still be behind on inoculations this summer. So does it make sense to have travel corridors to places with low infection rates or high vaccination rates?

Pitt: It does make some sense to have travel corridors between countries with low infection and/or high vaccination rates. However, governments would have to agree on the risk they were prepared to take in summer 2021. Would it only be travel for people from low infection/high vaccination countries to other similar countries? Would that mean that people in countries where the vaccine has not been made available yet would be prevented from travel?

Baker: Sarah, vaccine developers are working on new shots that target the new variants. When do you think we will start getting boosters? Six months? A year? And won’t that add another layer of complexity to travel to show you’ve had your booster?

Pitt: The vaccines that are being widely used at the moment used very new science and technology, and that’s why they were produced so quickly. Now the scientists and manufacturers know what they are doing, they could tweak the vaccines and produce new versions within months. So, yes, six months would be reasonable. It may introduce extra complexity, but I would expect a full course (two doses for most vaccines) to give a satisfactory level of protection.

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