What to know about the booster shot!

October 22, 2021

You may be worried that your immunity against COVID-19 is dwindling.

If you were fully vaccinated more than 6 months ago, it may be, says Binita Patel, PharmD, MS, vice president of pharmacy services at Memorial Hermann Health System.

So when should you get a booster—and when will you be eligible?

Here’s the real deal from Dr. Patel:   

Q. I heard boosters were recommended after 8 months. Now I’m hearing 6 months. Why the change, and what does it mean for me?

Originally experts thought immunity would remain high for 8 months. The U.S. Centers for Disease Control and Prevention revised the timeline after its Advisory Committee on Immunization Practices (ACIP) studied the latest data. “It shows immunity begins to wane at 6 months,” Dr. Patel says.

Q. Should I get an antibodies test?

No. That step is unneeded, she says.

Q. Should I get my booster now?

For individuals who received a Pfizer-BioNTech or Moderna COVID-19 vaccine, the following groups are eligible for a booster shot at 6 months or more after their initial series:

  • 65 years and older
  • Age 18+ who live in long-term care settings
  • Age 18+ who have underlying medical conditions
  • Age 18+ who work or live in high-risk settings

For the nearly 15 million people who got the Johnson & Johnson COVID-19 vaccine, booster shots are also recommended for those who are 18 and older and who were vaccinated two or more months ago.

There are now booster recommendations for all three available COVID-19 vaccines in the United States. Eligible individuals may choose which vaccine they receive as a booster dose. Some people may have a preference for the vaccine type that they originally received and others, may prefer to get a different booster. CDC’s recommendations now allow for this type of mix and match dosing for booster shots.

Q. Can I wait longer?

You can, but since your immunity starts to dwindle at 6 months, you could be more vulnerable to catching a mild to moderate COVID-19 case. It’s best to get your follow-up shot.

Q. Must I get the same vaccine as before?

The FDA has approved the use of each of the available COVID-19 vaccines as a heterologous (or “mix and match”) booster dose in eligible individuals following completion of primary vaccination with a different available COVID-19 vaccine. The approved single boosters include Pfizer-BioNTech, Moderna and Janssen (Johnson and Johnson).

For more information, click here.

Q. What will happen to my immunity over time if I don’t get a booster?

Your protection against the coronavirus and future variants (such as delta) will continue to drop, making you more vulnerable to variants. “The nature of viruses is to replicate and transform over time, so there will be more variants,” Dr. Patel says.

Q. Can someone receive a booster at a different location than the previous doses?

Yes. Bring the vaccination card that you got at your first inoculation appointment. It shows which vaccine you received and the dates of your shots. If you do not have or misplaced your original card, contact the site where you got your first shot or your state health department to find out how you can get another one. Those who enrolled in v-safe or VaxText after their first dose can access their records via those tools.

Q. When will boosters open up to the general public?

“That’s yet to be determined, though studies are being reviewed,” Dr. Patel says. “It may happen by the end of this year.”

Q. What are the side effects for booster shots? 

Soreness and redness at the injection site that lasts a day or so is most common. Fatigue or mild fever and stomachache are possible. “Consider those a good sign: Your body thinks it has an infection and is fighting it.” But fear not: None of the vaccines contain the actual virus, so you cannot catch coronavirus from them.

Q. Could an oral pill replace vaccines and boosters?

It’s possible that an antiviral pill called molnupiravir will be an option. The oral drug from Merck and Ridgeback Biotherapeutics slashed by half the risk of hospitalization or death in non-hospitalized adults with mild-to-moderate COVID-19 cases. Merck plans to ask the FDA for Emergency Use Authorization (EUA), following a large-scale trial which was stopped early due to clear benefits.

The information in this article is accurate as of October 22, 2021.

In Dec. 2021, the CDC issued a preferential recommendation for the use of the mRNA COVID-19 vaccines currently available in the U.S. (Pfizer and Moderna) over the Johnson & Johnson vaccine, citing rare but serious side effects. Throughout the pandemic, Memorial Hermann has closely followed guidance from the CDC as well as the U.S. Food & Drug Administration (FDA) and the State. As such, Memorial Hermann now recommends the Pfizer and Moderna COVID-19 vaccines over the Johnson & Johnson vaccine for those who meet vaccine eligibility.

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