SAN DIEGO COUNTY, Calif. — While most people think of a "passport" as a government-issued document, a "vaccine passport" would take the confirmation on paper that you've been immunized against COVID and turn it into an encrypted digital record on your cell phone to verify your vaccination status.
As the economy continues to reopen, more and more businesses - from restaurants and bars to stadiums and concert venues to airlines and cruise lines - are determining whether and how to prove their customers are fully vaccinated.
Already, at least 17 companies are developing vaccine passport apps for use in the United States.
New York State is now offering an option for residents called the "Excelsior Pass" and the United Kingdom is launching its own vaccine credential this week. In Israel, where most of the economy has been reopened for months now, the "Green Pass" - its version of a vaccine passport - is required of residents to scan in in order to get in places from hotels to gyms to concerts.
"It is all set in the telephone," one Israeli woman explained, showing off her Green Pass. "It is very convenient."
And while some view the vaccine passport as a 'convenience,' for others it is a source of controversy, leading to protests, like a recent one in Orange County.
It is a contentious issue that has ignited a growing debate over private rights and public health.
"I think it should be a choice," said one air traveler, while another said, "I personally think it's fine if we're protecting other people."
"We should show we're vaccinated," another passenger said.
But one woman speaking at an Orange County Board of Supervisors meeting was adamantly opposed.
"It shows me your papers before you pass!" she shouted. "It is an electronic dog collar."
"Vaccine passports or vaccine authentication will be the 'masks' of 2021," said Dr. Robert Wachter, chair of the Department of Medicine at UC San Francisco.
He said he supports the concept of a vaccine passport within reason.
"I think it is clearly legal; it is ethical because people who are not vaccinated have made a choice," Dr. Wachter told New 8. "And nobody is preventing them from not being vaccinated."
Dr. Wachter added that, aside from children under 12, only a minuscule portion of the population - less than 1% - is unable to get the vaccine for medical reasons.
"More than 99% of non-children are able to get the vaccine," he said. "And if they are not getting it, they have made a choice not to."
Opponents of vaccine passports, however, argue that requiring a form of vaccine verification would rob people of their right to choose.
"That is something that is utterly incompatible with a free society in my view," said California Assembly Member Kevin Kiley, who has introduced legislation that would ban the use of vaccine passports by any government entity in the state.
"I think it's a fundamental issue of privacy and personal liberty," Kiley told News 8. "You should not be forced to forfeit personal health information just to go about your daily activities."
As it stands now on the federal and state levels, there are no plans for the government to mandate a vaccine passport system, leaving it up to individual businesses to decide.
This is a stance that San Diego has taken as well.
"In terms of a formal, county-issued vaccine passport, that is not something that we will be pursuing," said San Diego County Board of Supervisors chair Nathan Fletcher.
For Assembly Member Kiley, though, the prospect of the business sector requiring a vaccine passport is tantamount to discrimination.
"To say that you show your papers and you can go there, while if you didn't show your papers, so you have to go there," he said. "You're not allowed to mingle with one another, you're not allowed in the same space, even if you are both just fine with it. I think that's not who we are as a state and as a country."
Dr. Wachter has taken a different stance.
"In the case of infectious diseases, we do not as a society bless the idea that 'it is your body and you can do what you want for yourself,'" Dr. Wachter said. "There are certain areas where we require vaccination because a decision that somebody makes about their vaccination actually impacts the entire community."
While the Biden administration has said it will not mandate the use of vaccine passports, which are expected to be free, it will provide guidelines to those companies currently developing vaccine passport apps, focusing on issues such as accessibility and privacy.
WATCH: Everyone 12 and older now eligible to receive the Pfizer vaccine