SAN FRANCISCO (KGO) -- California won't reach herd immunity by June 15 when the economy is set to fully reopen, but San Francisco will come very close.
Several top epidemiologists predict San Francisco is around three weeks away.
"I'd say it's pretty close," said UCSF Dr. George Rutherford.
79% of San Franciscans 12 and older have received at least one dose, according to the latest county health data. 68% of San Franciscans 12 and older are fully vaccinated.
"There is no other city that has these numbers of first dose vaccinations, even in places that vaccinated faster than we," said UCSF Dr. Monica Gandhi.
The only other Bay Area county that comes close? Marin County with 65% of the eligible population fully vaccinated, according to ABC7's vaccine tracker.
Compared to the rest of the state, San Francisco is still ahead of Los Angeles County where 53% of residents are fully vaccinated and San Diego County where around 50% of residents are fully vaccinated.
California's target date to reach herd immunity levels has consistently been predicted to happen by mid-July. Now, that the pace of vaccinations has slowed down, it may take longer.
"I think on a practical point we're closing in on it now, as far as a formal definition of 75% of people vaccinated, including children, I think it's going to take longer towards the end of the summer," said Rutherford.
The state is administering around one million doses every five days, according to ABC7's data analysis. If that pace keeps up, Rutherford says it's likely California will reach full herd immunity levels by mid-September.
"I agree with that, that we are getting there," said Gandhi.
Dr. Gandhi says the real indicator will come after the economy reopens on June 15. Will cases stay low? That will be our answer.
There will be more mingling, there will be people around each other, we're going to watch those cases very carefully and if they don't go up which I suspect they won't, that's when you say, yeah, we've gotten to herd immunity," said Gandhi. "You have to test it with human interaction within the population."
According to the CDC, people should only get tested if they have respiratory infections, or severe flu like symptoms, but it's not recommended for asymptomatic surveillance testing.
It's a similar answer for antibody tests, Rutherford explains they will not work properly if you've been vaccinated.
"We just don't have any great tests that say whether the vaccine has worked or not," he said.
It's very rare.
According to CDC data, in the U.S., one out of every 11,000 vaccinated people got reinfected with the virus. In California, state records show one out of every 7,000 vaccinated people got reinfected.
VACCINE TRACKER: How California is doing, when you can get a coronavirus vaccine
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