SAN FRANCISCO (KPIX 5) – With COVID-19 vaccine efforts ramping up, the Chase Center in San Francisco is eyeing a return to live concerts as soon as this fall.

A Bell Biv Devoe concert that was originally scheduled for March has been rescheduled for October 2nd.

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KPIX 5 asked epidemiologists if that date is realistic.

“Hopefully by the fall. It depends on what proportion of people are vaccinated,” said Dr. George Rutherford of the UCSF School of Medicine.

Dr. Monica Gandhi, also of UCSF, agrees.

“We will get to mass herd immunity by the fall. I used to say the summer, but when I saw the vaccine rollout I’m like okay, let’s give it ’til the fall,” Gandhi said.

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The magic number for mass gatherings, such as Giants games at Oracle Park or Warriors games at Chase Center is 70% of the population vaccinated.

“It takes away severe disease. That’s exactly what all of these vaccines do and then it gives people enough immunity that if the virus is bopping around it can’t find anyone to infect,” Gandhi told KPIX 5.

Until that 70% threshold is reached, Rutherford said proof of vaccine could be required to participate in large gatherings.

“I don’t think it’s such a stretch to think about having that as a criteria for being able to do things,” he said.

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Gandhi said it is okay to go ahead and start planning once again for a future outside the four walls of your home. “Think about next Christmas where you want to go, think about your vacation you can go wherever you want,” she said.