"It's not a booster because it's not specific for some of the variants, which the booster ultimately will be," says Dr. Colwell.
SAN FRANCISCO (KGO) -- Even though the CDC is not recommending a booster shot at this time, Zuckerberg San Francisco General Hospital and San Francisco's Department of Public Health have decided to allow an extra coronavirus vaccine for people who got the single-dose Johnson & Johnson vaccine.
The new dosing allowance seems to be unique to San Francisco. The hospital's chief of staff does not know of any similar guidance elsewhere at this time.
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ZSFG says people who got J&J will be able to get a second shot of either Pfizer and Moderna by the end of the week at their vaccine clinic. But "booster" is not the word health officials are using to describe it - instead San Francisco's Department of Public Health is calling it a "supplemental dose."
"It's not a booster because it's not specific for some of the variants, which the booster ultimately will be," said Dr. Chris Colwell, chief of emergency medicine at Zuckerberg San Francisco General.
On Monday, Dr. Colwell voted to allow the hospital's vaccine clinic to give a supplemental mRNA vaccine to somebody who had the J&J shot.
"Potential benefit, no downside. To me, as we look at the future of this virus and now we're facing a fourth surge, it does make sense," he explained.
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665,000 San Franciscans have been vaccinated, but only about 7-8% of them have received the Johnson & Johnson shot.
"People are worried about breakthrough infections, people were having concerns about whether that single dose was going to be enough," said Dr. Lisa Winstson, ZSFG's Chief of Staff and Hospital Epidemiologist.
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That concern is why Dr. Winstson says some people have gone out to get extra vaccine doses on their own. She supports the supplemental dose, but wants to be clear there's not enough data yet to support any possible benefit.
Dr. Lisa Winstson: "There's not a specific recommendation to give it. It's not part of the emergency use authorization."
Kate Larsen: "But you think it's safe?
Dr. Lisa Winstson: "Yeah, we do think it's safe."
San Francisco General is prioritizing City residents, but Dr. Winston says as long as their clinic has space and adequate vaccine supply, they will give the mRNA supplement to people from other counties.
SFDPH released the following statement:
"The San Francisco Department of Public Health (SFDPH) is currently accommodating special requests from individuals who have received the Janssen (Johnson & Johnson; J&J) viral vector COVID-19 vaccine and in many cases have consulted with their doctor and wish to receive a supplemental dose with an mRNA vaccine (Pfizer or Moderna). This move does not represent a change in policy for SFDPH. We continue to align with the Centers for Disease Control and Prevention guidance and do not recommend a booster shot at this time. We will continue to review any new data and adjust our guidance, if necessary."
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