Many computer developers are trying to come up with a digital health certificate accepted worldwide that can verify whether you've been tested for COVID-19 or vaccinated.
Some say the certificate -- which would provide verification that someone is COVID-19 free based on testing or proof of vaccination -- may be required to travel in 2021or participate in events where they are likely to encounter crowds.
In fact, the nonprofit organization the Commons Project has a digital platform called Common Pass that is already being tested in major market cities.
"We expect that many other institutions and communities will put in place requirements for not just negative testing but also vaccines and vaccinations," the Commons Project's CEO, Paul Meyer, said.
With the digital certificate, you could keep your medical records confidential but show that you are coronavirus-free, Meyer said.
“It's not that difficult, because you just link your Common Pass to the source of the data -- like your hospital information system," Meyer said. "Then, basically use it to demonstrate your status to that destination."
Critics of digital health certificates fear private medical information could be hacked or stolen.
“It is safe because, ultimately, the individual is the one in control," Meyer said. "There is no central database and no data stored in the cloud."
Requiring proof of vaccination is nothing new. Some countries still require yellow-fever vaccination certificates to enter, Meyer said.
"This is something we have been doing, not just for international travel and the yellow fever vaccine, but to register kids for school in September, and for summer camp and sports teams,” Meyer said.
Unlike paper certificates, Meyer said digital certification prevents forgeries.
"Really, what we are doing is allowing people to enforce their individual rights under [the Health Insurance Portability and Accountability Act] -- to get control of their health information, then make a decision whether they want to share it," Meyer said.
Common Pass is going through trials on flights between Hong Kong, Singapore, London and New York.
The Commons Project is currently working with 40 countries, Meyer said.
"By giving people the ability to demonstrate and to prove that they have either been tested or gotten vaccinated is part of allowing us to get back to life safely," Meyer said.
While many U.S. states and cities are maintaining vaccine databases, very few have embraced vaccine apps so far.