| The WHO has been issuing so-called Yellow Card certificates for decades. There are enough countries which will require vaccination against Polio, Yellow Fever and Meningococcal meningitis in order for you to cross borders. https://en.wikipedia.org/wiki/International_Certificate_of_V... Moreover, one of the first international certificate issued (1944) targetted Smallpox vaccinations and it's proliferation coincided with the booming air travel in the 1960's and 1970's. It is argued that the certificate was substantial towards preventing Smallpox from spreading in an age where endemic regions became only a few hours of flying away. https://en.wikipedia.org/wiki/International_Sanitary_Convent...
https://en.wikipedia.org/wiki/International_Sanitary_Convent... The United States signed and ratified the Convention back in 1945, essentially acknowledging that countries are able to require U.S. citizens to have a vaccine certificate. While the Convention dates back 75 years, today's Yellow Card is the de facto standard for certifying that you have gotten shots at a border. COVID-19 poses a challenge as this disease is highly infectious and crippling enough that preventing spread has become a far bigger global priority then other infectious diseases such as Yellow Fever. However, as of yet, a digital, secure, widely adopted solution that goes beyond the WHO's Yellow Card is still in the works. Several airlines and the IATA are working on their own travellers pass, but realistically, a trusted vaccination passport which is globally recognized requires an international treaty between nations governments. The world hasn't arrived at this point yet, and most countries still operate their own systems such as passenger locator forms or national passes issued to their own citizens. https://en.wikipedia.org/wiki/Vaccination_requirements_for_i... |