Dr. Monica Gandhi is an infectious disease doctor and professor of medicine at UCSF.
"I think it's a great idea," said Dr. Gandhi. "It does encourage the unvaccinated to get vaccinated. The second thing that it does is though the delta variant is very transmissible, it is not as transmissible among vaccinated people as unvaccinated."
San Francisco Director of Health Dr. Grant Colfax said Tuesday San Francisco is exploring the possibility.
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"We're very supportive of businesses and other entities requiring proof of vaccination for people to enter the premises," said Colfax.
This is something San Francisco Supervisor Matt Haney also supports.
"At this critical time when cases are going up and up in small quarters you should be vaccinated and you should be able to demonstrate that," said Haney.
Contra Costa County tells ABC7 News it has no plans to implement a vaccine passport program or require proof of vaccination to enter restaurants or other indoor public spaces.
San Mateo County also says it is not considering additional mandates at this time.
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However Supervisor David Canepa feels otherwise.
"The county of San Mateo has not officially taken a position on doing this but I do feel like the other counties, it's something that seriously is being considered."
Oakland Mayor Libby Schaff appeared on ABC7 News Midday Live where she said she hoped it would not be necessary.
"You know we always have to put sanctity of life first but my understanding is it should not be necessary," said Mayor Schaff.
Dr. Gandhi says she understands a vaccine passport system is controversial but likens it to anti-smoking campaigns.
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"It's not unprecedented in our country to use these sorts of incentives to make life more inconvenient when there's a safe and effective vaccine available," said Dr. Gandhi.
While counties consider the move, some health officials are already on board.
"I know it's not easy but I think it will make a difference in NY and I think it would make a difference here," said Dr. Gandhi.
Take a look at all of ABC7's Building a Better Bay Area stories and videos here.
VACCINE TRACKER: How California is doing, when you can get a coronavirus vaccine
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