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COVID-19 Update: Boosters, Floosters and the Omicron Variant

Infectious disease experts discuss the latest on COVID-19 boosters, timing flu shots and the Omicron variant.

Editor’s note: This article was updated from an earlier version posted in December 2021.

As the COVID-19 pandemic approaches its two-year anniversary, it’s normal to feel fatigued over the seemingly never-ending vigilance we’ve all had to maintain to safeguard our health. However, it’s important to continue to take the necessary steps to ensure that you and your loved ones reduce your risks for COVID-19 and other seasonal ailments like the flu.

Now is the perfect time to get your vaccine booster and “flooster” shots. We spoke with infectious disease physician Dr. John Zurlo about what you need to know now about COVID-19 vaccines, boosters and flu shots, and how to keep yourself safe. Plus, infectious disease physician Dr. Eric Sachinwalla weighs in on Omicron and what, if any, lifestyle changes we should make to stay safe.

Boosters for COVID-19

“Boosters for COVID-19, at least now in late 2021, seem to be necessary to improve the immune response,” said Dr. Zurlo. “There’s reasonable evidence that immunity from the initial two-dose vaccine has waned. We have preliminary evidence showing a reduction in new cases among those who had gotten booster doses.”

The United States passed another important milestone on Nov. 19, 2021, when the U.S. Food and Drug Administration (FDA) amended the emergency use authorizations for both the Moderna and Pfizer-BioNTech COVID-19 vaccines. All adults 18 years old and older are now eligible to receive a single booster dose after completing a primary vaccination with any FDA-authorized or approved COVID-19 vaccine. [Editor’s Note: As of December 9, 2021, the CDC has expanded COVID-19 booster recommendations to 16 and 17 years olds. At this time, only the Pfizer-BioNTech COVID-19 vaccine is authorized.]

This means that if you are an adult who received the Moderna or Pfizer vaccine, you can get a booster shot at least six months after your second dose of the primary vaccination. If you received the Johnson & Johnson vaccine, you can get a booster shot at least two months after your primary vaccination.

Mixing Your COVID-19 Booster Is Safe

If you’re like most people, you may be wondering if it’s safe and effective to switch brands between your original COVID-19 vaccine and your booster shot: If you received a Moderna vaccine originally, is it OK to get a Pfizer booster, and vice-versa? What about Johnson & Johnson?

“You can mix and match vaccines with your booster. In fact, some studies suggest there may be a better immune response when you do,” said Dr. Zurlo. “If you can get the same vaccine you started with, go right ahead—the most important takeaway is to get boosted when you are eligible.”

Flu Shot Can Be Timed With Booster Shot

You may be tempted to skip the flu shot this year since you’re already getting another booster, but it’s important to get your flu booster—or “flooster”—as well. Tens of thousands of Americans die from flu every year, so getting your annual booster is an important part of a healthy lifestyle.

“The Centers for Disease Control and Prevention (CDC) says that it’s safe to get both the COVID-19 booster and flu shot simultaneously,” said Dr. Zurlo. “This means you can get both shots during the same appointment without any additional risks.”

Risks associated with getting both shots at the same time are the same as they are for either shot. You may experience localized pain at the injection site, and some mild systemic side effects like a low-grade fever or fatigue for 24 to 48 hours.

“COVID-19 vaccines and boosters are extremely effective at reducing the severity of illness if you do become infected, and help most people avoid hospitalization and death,” said Dr. Zurlo. “Getting a COVID booster along with your flu shot can help you avoid or reduce the effects of illness over the cold winter months ahead.”

On the Omicron Variant

Scientists are still investigating the major questions surrounding the Omicron variant, including its degree of infectiousness and vaccine efficacy, which was marked a variant of concern by the World Health Organization (WHO) on November 26, 2021. “The Omicron variant has several mutations, or changes in its genetic material, that may cause it to be more infectious or more resistant to vaccines/therapies,” explains Dr. Sachinwalla. “Unfortunately, because it was just discovered the studies to investigate how these mutations affect its clinical impact haven’t been completed yet.”

Dr. Sachinwalla cautions that while there are still many unknowns about this variant and scientists are taking it very seriously and actively looking into the clinical impact that this variant may have, it’s cause for concern, not panic, as recently stated by President Joe Biden. “The most important thing I would suggest to anyone who has concerns about the Omicron variant is that this is another really good reason to make sure anyone who is eligible for vaccination gets vaccinated,” Dr. Sachinwalla says. “Even if the vaccine provides somewhat partial protection against the variant, it’s better than zero protection from remaining unvaccinated” He also strongly suggests mask use in public settings and even outdoors if social distancing is challenging. “I personally continue to wear a mask anytime I’m in public unless I’m able to really distance from others,” he adds. “If you haven’t been judicious about mask use in public settings, this is the time to start wearing masks in public again.”

If you’re on the fence about gathering with friends and family this holiday season or upcoming travel plans, Dr. Sachinwalla says it’s still early to say people should be canceling their plans but emphasizes the importance of getting vaccinated. “It’s more important than ever that people who are traveling or gathering with other people, especially in crowded indoor settings make sure they’re fully vaccinated and have received their booster if eligible,” he urges. “We know that the vaccines work very well against the Delta variant and that currently remains the predominant variant in our area.”

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COVID-19, From the Experts