SAN FRANCISCO (KGO) -- Will we ever reach herd immunity? Top doctors say it may never happen.
"It's sad," said UCSF's Dept. of Medicine Chair Dr. Bob Wachter. "It's possible we will never reach herd immunity."
Herd immunity is when a portion of the population that becomes immunes from infection that protects the entire community and not just those immune. San Francisco was pegged to be the first metropolitan city to reach herd immunity a couple months ago, but Wachter says the Delta variant has changed everything.
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"It's a bummer," he said. "The level of protection that we thought was going to be associated with herd immunity is no longer high enough."
Reaching herd immunity symbolized control of this pandemic, a step back to normalcy. For San Francisco that meant reaching 75% of the population fully vaccinated.
"We are at about 75% of San Francisco immunized, probably about 80% if you include prior infection and we're still seeing a heck of a surge," he said. "It surprised all of us."
Wachter says the need for ramping up vaccinations has never been more important.
"Delta was worse than Alpha, Alpha was worse than the original," he said. "It's not at all impossible that we will have a variant that's even worse to evade the vaccines."
Most of the Bay Area adopted an indoor mask mandate this week. Should vaccines be next?
New York State is now mandating proof of vaccinations for workers and customers for things like indoor dining, gyms, and concerts.
Stephanie Sierra: "Do you think we should consider that here?"
Bob Wachter: "We should certainly consider it. I think we have to do everything we possibly can to make workplaces, places of dining and entertainment safe and we also have to do everything we can to get vaccine rates up."
Wachter says it is possible we could reach a point where additional restrictions on bars and restaurants are needed, like capacity limits or social distancing requirements.
"I think there's nothing that's off the table," he said. "None of us want to go backwards, everybody loved May or June when it felt back to normal, but the virus couldn't care less. This virus is so much better at its job than the original."
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SF General is now offering patients who received the Johnson and Johnson vaccine a supplemental booster shot of Pfizer or Moderna.
Stephanie Sierra: "Do you recommend both doses or is one sufficient?"
Bob Wachter: "It's probably overkill. The benefit after that first booster after the Johnson and Johnson vaccine is so high that I think there's no need to get a second Pfizer dose or second Moderna dose."
Wachter says UCSF Medical Center is also considering offering supplemental booster shots to staff and patients who received the Johnson and Johnson vaccine but the hospital system is still waiting for the federal guidelines on boosters to be released first in the next few weeks.
How often should we get tested for COVID? Should we get tested even if we're asymptomatic?
"I think a widespread strategy of asymptomatic testing is unpractical," said Wachter. "If you have any symptoms you should be tested. If you're anxious after getting off a plane from an area with a high prevalence rate you should get tested."
Wachter also recommends regular testing for anyone in contact with people who are immunocompromised.
"But to do routine asymptomatic testing twice a week, it just doesn't compute."
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