5 Things To Know About Coronavirus Booster Shots In CA

CALIFORNIA — As the highly transmissible delta variant sweeps the nation, federal officials recommended this week that all vaccinated Americans get an additional vaccine shot. In California, eligible residents could have access to a booster shoot as early as late September.

The news, announced Wednesday, came a day after the state OK'd additional shots for immunocompromised residents. And while experts maintain that vaccinated Californians are still protected, they also say a booster shot will bolster immunity against the supercharged delta variant.

Here's what we know about the new shots.

1. A third shot is recommended eight months after being fully vaccinated.

The immunity granted by coronavirus vaccines was always expected to wane over time, but up until recently, it wasn't clear exactly when that would happen.

A number of recent studies suggest that while vaccines still offer protection against severe illness and hospitalization, breakthrough infections resulting in mild illness have become more common since the delta variant gained dominance in California.

"So what their data show is that your neutralizing antibody levels decay over time," Dr. Timothy Brewer told Patch. He's a professor of infectious disease at the David Geffen School of Medicine at the University of California, Los Angeles. "For the Pfizer vaccine, they decay about 6 percent every two months or so."

Federal officials announced Wednesday that another shot was recommended eight months after receiving a second injection of Pfizer or Moderna. When faced with the particularly sticky delta variant, booster shots are meant to restore immunity levels, new — albeit limited — data has shown.

"Even though the neutralizing antibody levels seem to be falling, they seem to be protecting very well still against serious disease and hospitalization," Brewer said. "They're clearly still generating effective immune responses, though breakthrough infections, including mildly symptomatic infections, do increase over time."

Experts maintain that the introduction of additional shoots is not a testament to how well vaccinations work, but rather a response to an unprecedented variant.

"The fact that we need a third jab and the fact that we are still asked to wear masks indoors and be careful is a testimony that we're facing a really formidable foe," Dr. John Swartzberg, a professor of vaccinology and infectious disease at the University of California, Berkeley, told Patch

2. Immunocompromised Californians are first in line.

Booster shots were swiftly approved this week for Golden Staters who are immunocompromised as the delta variant continued to pose a threat to vaccinated high-risk residents. Vulnerable residents were advised to get a third shot 28 days after their last dose.

Recent studies have shown that the first two doses of Pfizer or Moderna are less effective for those with hampered immune systems, offering 59 to 72 percent effectiveness instead of 90 to 94 percent effectiveness among those with strong immune systems, NPR reported.

"While people who are immunocompromised make up about 3 percent of the U.S. adult population, they are especially vulnerable to COVID-19 because they are more at risk of serious, prolonged illness," Centers for Disease Control and Prevention Director Dr. Rochelle Walensky said in a statement.

High-risk residents are also more likely to experience a breakthrough infection.

"Emerging data have demonstrated that immunocompromised people who have low or no protection following two doses of mRNA COVID-19 vaccines may have an improved response after an additional dose of the same vaccine," officials from the CDC said in a statement Wednesday.

3. What do we know about the side effects of the booster shot?

"Very little," Swartzberg said. "We have given the third shot to some groups of people and so we know that it should be well-tolerated, and we haven't seen any signals...Can we expect them to be similar to getting a second shot? Yes, I think so."

To be clear, the so-called booster shot is merely a third round of either Moderna or Pfizer, so experts are not anticipating many surprises in terms of adverse effects.

Those who didn't experience the brief flu-like symptoms that came with the first two vaccine shots likely heard about them. While those side effects were different for everyone, experts assured that those symptoms were an appropriate and normal immune response.

Some early data suggested that mixing different vaccine shots — Moderna and Pfizer — could spur amplified side effects, but they likely wouldn't differ from the expected symptoms, Brewer said.

"The short answer is, we don't really know about them (side effects) because so far the only people who have gotten booster shots have generally been immunocompromised, so they tend not to react to the vaccines as much as the general population," Brewer said.

Early data from small studies showed that booster doses in high-risk patients did not result in severe or adverse effects, according to multiple reports. Many reported that their side effects were similar to what they experienced after the initial two doses.

4. What about those who got the Johnson & Johnson vaccine?

Those who received the Johnson & Johnson vaccine were not advised to seek out a booster shot just yet since health officials are still researching whether one is necessary for that group.

"If you look at the data that are coming out, [all the vaccines are] actually still holding up very well," Brewer said.

A recent study out of South Africa showed that the single-shot vaccine was still 71 percent effective against hospitalizations. That study also showed that the vaccine offered 91 to 96.2 percent protection against death, Reuters reported.

But there are fewer data available overall about the J&J product since it wasn't available to Americans until March, trailing Pfizer and Moderna. The vaccine is also made differently than the other two.

U.S. Surgeon General Vivek Murthy said last week that those who received the single-shot vaccine will "likely" need a booster shot.

"We believe that J&J recipients will likely need a booster, but we are waiting on some data from the company about a second dose of J&J so the FDA [Food and Drug Administration] can fully evaluate the safety and efficacy of that dose,” Murthy told CNN.

5. How important are booster shots to ending the pandemic?

The short answer: There isn't enough data to forecast their potential impact on the pandemic, but experts are hoping that a boost in immunity will help stall the spread as the state barrels toward the fall and another holiday season.

"I don't know what percentage of the population will have had the third jab within a week after Thanksgiving, which is when we could start to see a big surge of cases again," Swartzberg said. "But I think this third jab is going to help prevent what we saw last December and January. I don't know if it's going to be significant, but I think it will blunt what we otherwise would have experienced."

The mere mention of waning immunity in those who are vaccinated could sound alarming, but experts are urging that the vaccines are holding their own.

There's enough early data circulating around to suggest that booster shots will add a level of protection, but Brewer questioned whether a nudge to get additional shots could further discourage those who are vaccine-hesitant in California.

The introduction of a third shot could cause some to erroneously wonder "'why should I get a vaccine if it's not going to work for very long?"' he said.

Statewide, about 65.3 percent of California's near 40 million residents have been fully vaccinated, leaving a significant chunk of residents vulnerable and more likely to spread the virus. The virus also is more likely to mutate and create more variants if it continues to spread as rapidly as it has since the pandemic began.

"It's just that I'm not sure that's where the priority should be," Brewer said of booster shots. "Given that the efficacy (from current vaccines) against serious disease and hospitalization is holding up reasonably well, the real priority has to be interrupting transmission. And the best way to do that is not to give boosters to people who are already vaccinated — it's to vaccinate everybody who hasn't been vaccinated."