LAUSR

International travel is rebounding as coronavirus disease 2019 (COVID-19) vaccinations continue and more countries are opting for ‘living with COVID’ in the hopes of moving from a pandemic footing toward an endemic one. Such travel remains far from risk-free, however, given the existence of asymptomatic carriers and the emergence of new severe acute respiratory syndrome coronavirus 2 variants. To protect their residents, most countries have instituted policies requiring incoming travelers to be fully vaccinated according to their own policies and to show proof of a negative COVID test [1,2]. This has raised new challenges for everyone who wants to travel internationally, especially for those who have received vaccines not yet approved by the World Health Organization (WHO) and other regulatory agencies like the United States Food and Drug Administration and the European Medicines Agency. Residents of many low-tomiddle income countries do not have access to some vaccines approved by these entities. This generates clear inequalities in international travel policies around the world. The case of individuals vaccinated with Gam-COVID-Vac is an example. On February 2, 2021, the first study on the vaccine, produced by the Gamaleya Institute in Russia, reported on the safety and efficacy of this rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 jab (Gam-COVID-Vac or Sputnik V). The efficacy was 91.6%, similar to the mRNA vaccines BNT162b2 (BNT, Pfizer; Pfizer, New York, NY, USA) and mRNA-1273 (Moderna, Cambridge, MA, USA), and superior to the adenoviral vaccines ChAdOx1 nCoV-19 (AZD1222; AstraZeneca, Cambridge, UK) and Ad.26. COV2 (J&J/Janssen; Johnson & Johnson, New Brunswick, NJ, USA) [3,4]. Many countries as well as the WHO, have not approved vaccination with Gam-COVID-Vac waiting for reliable independent validation of its efficacy [5]. Yet, given the scarcity of WHO-approved vaccines, this vaccine has been used in at least 75 countries in Asia, Africa, and Latin America [6]. Consequently, many persons vaccinated with the Gam-COVID-Vac from these countries have experienced restrictions in their international movements. Beginning in November 2021, all travelers to the United States were required to show proof of being fully vaccinated as well as a negative COVID-19 test. Only WHO-approved vaccines were accepted, leaving persons who have had the Gam-COVID-Vac not considered fully vaccinated [7,8] and consequently unable to enter the United States. This complex situation also applies to those who got other COVID vaccines not approved by the WHO, including Cansino (CanSinoBIO, Tianjin, China), Novavax (produced in India), EpiVacCorona (VECTOR Center of Virology, Koltsovo, Russia), Abdala (Center © Korean Vaccine Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/ by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. K O R E A N V A C C I N E S O C I E T Y