70% of adults in California are at least partially vaccinated, which means more than 22-million COVID-19 vaccination records are floating around on paper and in digital records, leading some to question whether people's personal information is safe.
"There is a privacy issue, there is an ethical issue, there's a social issue with this information. It's not monitored and not organized," explained Ahmed Banafa, a cyber security professor at San Jose State University.
Banafa is concerned the information on the vaccine cards is not well protected and potentially tempting to bad actors, who may want to hack into health care information systems to, "steal identities," or open credit cards.
"The dark web is place where all that information can be sold and sold for a certain price, depends on how clean and important is the data. And the best data you can sell is the health care data because it's protected," Banafa explained.
But not everyone thinks vaccine data is rife with trouble.
"There's nothing new, there's nothing different, there's nothing nefarious about the system. It is one of the staples of public health," said Michelle Mello, a Stanford Law and Medicine professor and expert in public health law.
"Should we be concerned in general that hackers can access electronic health records? Absolutely, it's critically important to keep that information safe. Do these vaccination cards elevate the risk that we face every day? No, I don't think they do," she said.
Professor Mello's reasoning comes from the fact that most vaccine cards only contain a name, birth date, and vaccination information, which is basic to any vaccine record.
What's different, is that people are carrying the COVID vaccine cards to have as proof as the world reopens. And some of the cards do have medical record numbers, in which case, Mello suggests that people place a sticker over the number, if they show it to someone other than a medical provider, like at a workplace, business, or event.