By Allen Martin

By Allen Martin & Molly McCrea

SAN FRANCISCO (CBS SF) — The Delta variant has thrown the Bay Area a curveball. Those in gravest danger are without a doubt the unvaccinated or partially vaccinated.

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They represent the vast majority of reported new cases, hospitalizations, and deaths. But breakthrough infections are catching many by surprise.

At the SF Latino Task Force Hub, where health professionals test members of the community weekly, they have noticed an uptick in positive COVID tests among those who were fully vaccinated.

“We were only testing about 50 to 60 people,” said SF Latino Task Force Health Chair Jon Jacobo. “This last week, we tested close to 400 people and had a positivity rate of closer to 8% which is a dramatic difference from just June. And a good chunk of those people who tested positive were fully vaccinated.”

While no vaccine is 100% effective, KPIX News spoke to one fully vaccinated doctor who found out the hard way.

“I have so often opened my results and seen the negative results, that seeing the positive result was sort of surreal,” said UCSF pediatrician Dr. Marissa Raymond-Flesch.

On June 15th, when California reopened, nearly all pandemic safeguards vanished. In July, Dr. Raymond-Flesch took a tiny “stay-cation” with her family.

“I went on a boat ride in San Francisco Bay,” she told KPIX 5. “We stayed outdoors on the boat the whole time and then I ate outdoors once.”

She added that she attended a few small gatherings where all participants were fully vaccinated. By then, the Delta variant had arrived in the Bay Area and was percolating.

“We have a much more transmissible virus twice as transmissible as what the earlier ones, that can spread like wildfire,” noted UCSF epidemiologist Dr. George Rutherford.

Dr. Rutherford explained how the unvaccinated are the underbrush feeding the flames of the growing fire. Vaccinated individuals, he noted, are the collateral damage.

“So, as we get more and more and more transmission, you as a vaccinated person have more and more risk of being exposed,” said Dr. Rutherford.

Dr. Raymond-Flesch believes she caught COVID outdoors, which was a scary conclusion for her. She woke up with a tickle in her throat and mild congestion. By the end of the day, she had terrible muscle aches, more congestion, a sore throat, and a fever.

“I was sick. I was surprisingly sick,” noted the pediatrician.

The doctor then unwittingly gave the virus to her husband and their unprotected 2-year-old.

“I was terrified. I was really, really scared,” she said.

CDC data suggests infected vaccinated people can carry a large amount of the Delta variant in their nose and mouth. And that may put unprotected loved ones in danger.

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“They can still be transmitters of the virus to unvaccinated people,” explained Dr. Stephen Thomas.

Dr. Thomas is chief of infectious diseases at SUNY Upstate Medical University. He is tracking the long-term safety and efficacy of the Pfizer COVID vaccine at 150 sites around the world.

“Almost half a billion doses given globally, almost 200 million doses in the United States,” noted Dr. Thomas.

The scientist said at 6 months, the vaccine continues to strongly protect against severe illness and death. But in a recent non-peer reviewed study, he found that vaccine’s power wanes over time: about 6 % every 2 months. It’s a problem if the virus is surging in the community and transmitting at high or substantial rates.

“It increases the ante on us getting people vaccinated as quickly as possible,” cautioned Dr. Thomas.

It takes weeks before a newly vaccinated person can develop immunity. In a surge, experts recommend quicker action.

“We can wear a mask. That is going to break the chains of transmission,” explained Dr. Diane Havilar.

Dr. Havilar is a UCSF Professor and Chief of the HIV, Infectious Diseases and Global Medicine Division at Zuckerberg San Francisco General.

“We can also have more testing. If a person has been exposed to somebody who has active COVID, then they should go and get tested,” remarked the infectious disease specialist.

One way to dramatically increase vaccinations is now in the hands of the FDA.

“It’s very important to license the vaccine because there is still a lot of individuals who are concerned that it’s an “experimental vaccine,” said Dr. William Schaffner.

Dr. Schaffner is an infectious disease specialist at Vanderbilt University Medical Center.

He told KPIX 5 that once the FDA approves and licenses a COVID-19 vaccine, then it will be easier to require it.

“There are many entities, governmental and private who would if the vaccine were licensed, issue mandates,” remarked Dr. Schaffner.

As for Dr. Raymond-flesh, she said without a doubt getting vaccinated saved her from landing in hospital or worse. Her husband and child had bad colds but have since recovered.

“I’m so grateful for my vaccine and I genuinely hope and plead with anyone who is eligible to get a vaccine that they get vaccinated,” said the pediatrician.

According to a new report from the Kaiser Family Foundation the information on breakthrough cases is limited and incomplete. Not everyone with symptoms is getting tested in a robust fashion.

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However, among those who are hospitalized with d=Delta or have died from COVID during this ongoing 4th surge, the vast majority are unvaccinated.