How long will my COVID-19 booster last? What to know as California cases surge

·3 min read

As California experiences an surge in COVID-19 cases, unvaccinated and vaccinated individuals, including those who received the booster shot, remain susceptible to catching the virus.

Booster shots, which first became available to immunocompromised Americans in August, offer an additional layer of protection against the virus. By December, nearly a quarter of fully vaccinated adults received the first booster shot, according to Kaiser Family Foundation COVID-19 Vaccine Monitor.

Is my first booster shot still effective?

For people with healthy immune systems, the booster is still effective against hospitalization several months later, said Dr. Dean Blumberg, UC Davis Children’s Hospital chief of pediatric infectious disease.

The booster only starts to fade in effectiveness against mild breakthrough cases four or five months after the shot.

But the third dose still provides “excellent protection” against severe disease, including hospitalization and death, for those with normal immune systems, Blumberg said.

“There is really limited evidence that there’s waning immunity for more severe disease for immunocompetent people,” he said.

While mild breakthrough cases can still result in symptoms like fever and coughing, hospitalization is less likely. And right now, the primary focus of health experts is minimizing severe cases to avoid overwhelming the health care system, he said.

The FDA authorized the Pfizer booster for healthy children age 5 to 11 on May 17. They must be five months out from their first shot. The U.S. Centers for Disease Control has not yet recommended the third shot, but is expected to meet Thursday.

Am I eligible for a second booster shot?

In late March, the FDA authorized a second booster dose for adults 50 or older and immunocompromised individuals 12 years of age and older — for those who received their first booster four months ago.

The CDC recommends people stay up to date on their vaccines, which only includes the first booster for eligible individuals.

“If you are eligible, it is up to you whether to get a 2nd booster right now, based on the benefits and risks of a 2nd booster,” according to the CDC.

Adults who received two doses of the Johnson & Johnson COVID vaccine, including the primary vaccine and booster, are also eligible for the second booster.

“For those with weakened immune systems, it is important to get that fourth dose,” Blumberg said.

In addition, he recommends people who may be in situations with an increased risk of transmission, such as traveling on planes where masks are not required, consider getting a second booster.

The CDC suggests people wait to get their second booster if they have had COVID-19 in the last three months or if getting one now would deter them from getting a booster in the fall, when it “may be more important.”

Blumberg said he believes new and improved vaccines will come along in the fall that will provide better protection against different variants. Transmission rates for COVID-19, he added, tend to go down during the summer due to warmer temperatures.

He recommends people get vaccinated, boosted if eligible and choose the second booster if they are at increased risk for severe infection. He also said individuals should mask when necessary to protect against the virus.

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