Even with the COVID-19 vaccine, international travel will likely depend upon tests to prove travelers are virus free. Healthcare experts say that passengers will need at least two, and sometimes three, COVID-19 tests before departure, upon arrival at their destination, and even during the trip.

According to Axios, proof of testing and vaccination will be the new norm as international travel and borders open up. Travel advisors say that shorter routes to Europe from North America are likely to recover first, but with mass vaccination probably not happening until the summer of 2021 and in some countries not until 2022 or 2023, testing is here to stay, along with basic preventive measures such as wearing masks and observing social distancing.

Delta Airlines recently announced its first COVID-free flight from Atlanta to Amsterdam that requires no quarantine after arrival. Passengers and crew must undergo pre-flight testing protocols that prove they are negative to COVID-19. The airline will add a similar flight from Atlanta to Rome on Saturday, December 19.

Those traveling to Amsterdam must test negative from a standard PCR test taken five days prior to arrival in Amsterdam as well as a rapid test at the Atlanta airport. A second PCR test will be done upon landing at Schiphol Airport, and if that result is negative, no quarantine will be required.

Testing is becoming easier and more available. This week the Food and Drug Administration (FDA) gave authorization for Australian manufacturer Ellume’s non-prescription antigen test that gives results at home in 20 minutes. There is also a new PCR test that works like a mouthwash rinse to accurately test for COVID-19. It’s been approved for use in Europe and is currently seeking FDA approval.

Some airlines are rolling out CommonPass, according to Axios, which is a collaboration between the World Economic Forum and Swiss-based non-profit The Commons Project. The CommonPass will be a globally interoperable platform for people to document their COVID-19 status to satisfy country entry requirements.

The International Air Transport Association (IATA) that represents 300 member airlines announced the development of the IATA Travel Pass, an app that would store documentation about COVID-19 tests and proof of vaccination. According to Newsweek, the app is expected to be available for both iOS and Android in March 2021.

Exerts told Axios that while vaccinations will likely be the passport for international travel from now on, since there are no uniform vaccine requirements worldwide, getting vaccinated in one country does not guarantee entry into another.