Do you need another COVID booster? We asked California infectious disease experts and the CDC

The end of the coronavirus’ spread may be unforeseeable — and questions about vaccines and boosters continue.

After publishing a COVID Q&A with Dr. Dean Blumberg, chief of pediatric infectious disease at UC Davis Health, The Bee continued to receive more questions — this time about the bivalent booster.

Several readers asked The Bee whether they need to go in for a second round.

Reader Mark Manz, wrote to The Bee that he is at high risk for COVID. Manz said that he received the bivalent vaccine and prior doses, but heard the new booster only lasts about six months.

“Is there an option for another shot/booster?” he asked.

Kim Christmann, another reader, wrote: “For people who have had one bivalent vaccination and all previously recommended shots, when should they get a second bivalent booster?”

To find the answers to these questions, The Bee spoke to the U.S. Centers for Disease Control and Prevention and two California infectious disease experts.

Is there an option for a second bivalent shot?

Currently, there is no guidance recommending people get a second bivalent booster dose.

“CDC is actively monitoring vaccine effectiveness,” Kate Grusich with the CDC’s public affairs wrote in an email reply, “but it’s too early to determine when protection from the updated (bivalent) COVID-19 vaccine may wane, as it was only authorized in the U.S. in September 2022.”

The CDC only recommends one bivalent shot as of now and is encouraging people who haven’t gotten a vaccine before September 2022 to get it soon to prevent severe disease and death — especially if they are older and have underlying conditions.

How long does protection last on the bivalent booster?

It’s unclear at this time.

Dr. Angelique Tjen-A-Looi, an infectious diseases specialist for Kaiser Permanente Sacramento and Roseville, said the bivalent is still being observed but if it’s like the previous vaccines and boosters — which offered protection up to 12 months — it’ll have a similar degree of protection.

Grusich said that from the original vaccines, it’s known that protection does decrease over time, especially against asymptomatic infections. But they last longer against more serious illness.

“So, it’s likely that people who have received the updated vaccine will remain protected against severe COVID-19 for a longer period of time,” she said.

Like the other vaccines, expect the bivalent booster’s protection to wane, said Dr. Otto Yang, an immunologist and professor of medicine in the division of infectious diseases at UC Los Angeles.

“The effect starts to wane after about four or five months,” said Yang, “but it’s not that it’s gone after four or five months.”

He explained that protection will steadily drop and will continue to taper off after a few more months.

“It’s not black and white that it’s suddenly gone,” he said.

Should people get a second booster?

If you’re immunocompromised or have conditions that make you at higher risk for severe disease, Yang recommends that you discuss this with your physician.

The CDC does have separate recommendations for those with weakened immune systems, which include three-series dose of the Moderna or Pfizer vaccine and the bivalent booster. Guidelines differ based on the vaccine brand and age of the patient.

For people who aren’t immunocompromised, CDC advises that they get the two doses and the bivalent booster.

In the case that you get sick despite being fully vaccinated and are at risk for severe illness, Yang said you should consider getting early treatment.

“The earlier you start treatment with Paxlovid or Remdesivir,” he said, “the better the outcome is, in terms of preventing disease from progressing.”

If you get COVID and need a prescription for medication or to fill them, you can search for the nearest clinic online.

Will there be a new booster?


Tjen-A-Looi said that she expects the federal government and the Food and Drug Administration are sponsoring vaccine manufacturers to continue to update the COVID booster.

“Currently, we expect the bivalent booster to be effective,” she said, “until presumably, the next one is available.”

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