By Da Lin

SAN FRANCISCO (CBS SF) — While widespread herd immunity against COVID-19 still remains elusive, some local infectious disease experts believe it has been achieved in some areas of the San Francisco Bay Area.

One of those pockets, UCSF infectious disease specialist Dr. Peter Chin-Hong said, is likely San Quentin State Prison, which was hard hit by a major COVID outbreak.

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More than 2,100 inmates have had confirmed cases of COVID since the outbreak began in the Spring 2020. Of those 28 died. Currently, 1,927 inmates are fully vaccinated.

He also believes it may exist among the local nursing home population.

“Another place where I can say we have almost herd immunity is the nursing home population because across the country, (the vaccination rate is) pretty high, above 70%,” Dr. Chin-Hong said. “In the Bay Area, it’s above 80%.”

Herd immunity can come from either a positive COVID-19 test or a vaccination. Both generate antibodies that fight the virus and the numbers suggest San Francisco is leading the Bay Area. The region has the highest percentage of vaccinated residents in California and among the lowest hospitalization rates.

San Francisco health officials said as of May 14th, 75% of San Franciscans over 16 years old have received at least one dose of vaccine.

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“Until we get global herd immunity, regional herd immunity may be just transient and fleeting depending on circumstances,” said Dr. Chin-Hong.

But most doctors admit global herd immunity is still a few years away because of the new variants, vaccine hesitancy, and vaccine equity.

In the Bay Area, the biggest challenge is vaccine hesitancy.

“I haven’t been vaccinated because there hasn’t been enough tests and I kind of feel like I don’t want to be one of the guinea pigs,” said William Luckett, a 60-year-old Emeryville resident who refused to get vaccinated.

Those who refused to get the shot told KPIX they don’t trust the science.

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“I don’t have trust in the systems like that. Because everybody you put your trust in let you down,” said Vernon Lewis, a 58-year-old Oakland resident who declined to get the shot.