New COVID-19 booster shots — specially formulated to fight multiple omicron variants — will be available by fall.

An advisory panel for the U.S. Food and Drug Administration (FDA) recently recommended approval of the new tailored COVID-19 booster vaccines, and the U.S. government plans to buy millions of vaccine doses for a fall booster campaign.

We consulted with infectious disease and COVID-19 expert, Dr. Thomas Campbell, to answer your questions about the newest COVID-19 booster shots and to learn more about who should get them.

Campbell ran clinical trials for COVID-19 vaccines at UCHealth University of Colorado Hospital on the Anschutz Medical Campus. He is also a professor of medicine and infectious diseases at the University of Colorado School of Medicine.

Why is there a new omicron-specific COVID-19 booster shot?

“The original vaccines are still very effective in preventing hospitalization and death from COVID-19. They are particularly effective in people who have received the recommended boosters,” Campbell said.

But it’s normal for viruses to change and for variants to develop, Campbell said.

In the case of SARS-CoV-2, the virus that causes COVID-19, multiple omicron variants have spread and become dominant throughout 2022. They include omicron variants known as BA.2, BA.4 and BA.5.

The original vaccines and boosters did not specifically fight these omicron variants because they hadn’t developed yet. The proliferation of omicron variants has prompted the primary vaccine makers who are supplying COVID-19 vaccines in the U.S. — Pfizer and Moderna — to create new, tailored versions of their booster shots that will better combat omicron variants. The vaccine makers have pledged to deliver the new doses by fall.

Some health experts have discussed the possibility of a combined vaccine protecting against both flu and COVID-19. Is it likely that we’ll get a combined vaccine this fall?

No. Not yet, Campbell said.

While it’s possible that we’ll be able to get combined flu/COVID-19 vaccines in the future, for now, vaccine makers and health experts have not yet created a new double-duty flu/COVID-19 vaccine.

If I never got vaccinated, should I wait and get the newest versions of the omicron-specific COVID vaccines this fall?

No. People who have never gotten COVID-19 vaccines should get their first two doses of the original vaccines as soon as possible. The new “recipe” of the booster shots was tested on people who already had their initial vaccine doses and one booster shot.

“I would strongly advise people who are not vaccinated at all to complete the primary series of two shots (with the original vaccine),” Campbell said.

If people have not received their first vaccine doses, will they get the new, updated omicron-specific COVID vaccines once they are ready?

No. People who have not received their first two vaccine doses — known as the primary series — still will receive the original vaccines. The original versions protect well against most strains of the virus. It’s important to note that no one knows yet precisely which strains of the virus will be circulating this fall or in the future.

“Even though we are dealing with omicron variants now, it’s still possible that another version of the virus — like delta or the original strain — could come back at a later time. So, we all need to make sure that we’re protected against the older variants,” Campbell said.

“When the new omicron-specific booster vaccines are authorized (and delivered), they likely will only be given to people who have already completed a primary series with the prototype vaccine.”

What if I’m eligible for COVID booster shots now and haven’t gotten them yet? Should I get a booster shot now or wait for the newest version of the omicron-specific booster once it’s ready in the fall?

Do not wait, Campbell advised.

If you have gotten your first two vaccine doses and are eligible for a booster shot, get it now. And if you’re eligible for a second booster shot, get it as soon as possible, Campbell said.

The newest variants are highly contagious and are spreading widely now. The current vaccines and boosters are helping to reduce the severity of illness and are preventing some hospitalizations. So, it’s wise to get fully boosted now, Campbell said.

Remind me again. Who should get COVID-19 booster shots, and what is the correct timing?

Adults who are ages 50 and older should get two booster doses. That’s also true for younger people who are immunocompromised or are especially vulnerable to getting severely ill with COVID-19.

Everyone ages 5 and older should get a booster dose after completing their primary series.

Babies and toddlers are now eligible for their first vaccine doses and are not yet getting booster shots.

It can be confusing to figure out who is eligible for booster shots and what the proper timing is. If you need help sorting out your specific situation and deciding when to get a booster shot, you can use a handy tool that health experts at the Centers for Disease Control and Prevention (CDC) have created.

Why is COVID-19 spreading so widely now?

There are three main reasons.

First, the newest omicron variants spread much more easily than previous versions, Campbell said.

Second, many people are not fully vaccinated.

“In the United States, only a small portion of the population has received one booster, and an even smaller portion of the population has received two boosters,” he said.

If more people can fully vaccinated and boosted, the spread of the current variants may decrease.

And third, antibodies from vaccines, booster shots or a COVID-19 infection decrease over time, making it easier for people to get infected for the first time or to get the illness again.

“With the omicron variant, after the first booster dose, the protection starts to really drop off by about six months,” Campbell said.

Researchers do not know yet how long the immunity after a second booster dose lasts.

What if I’ve had COVID-19 recently? Should I wait to get a booster dose or a second booster?

Yes. Research is showing that most people who have had a recent case of COVID-19 should have high antibody levels for about three months. So, they can wait 90 days after a COVID-19 infection to get their next booster dose.

“If you’ve just had COVID, there’s no rush to go out and get the booster. You can safely delay getting it for at least three months,” Campbell said.

Approximately when do the vaccine makers expect to have the newly formulated omicron COVID booster shots ready?

The vaccine makers have told FDA medical experts that they plan to deliver the newest booster doses by about mid-October.

Who will be eligible to receive the new versions of the omicron-specific booster shots?

Federal health officials have not decided yet who will be eligible to receive them.

Campbell expects that FDA and CDC experts will want vulnerable people — including those who are older, immunosuppressed or at risk for bad outcomes if they get COVID-19 — to be first in line to get the newest booster shots.

It’s possible, however, that federal officials will recommend the new omicron-specific booster shots for everyone, including younger people.

How are vaccine makers able to create new versions of the vaccines relatively quickly?

Both the Pfizer and Moderna vaccines are a newer type of vaccine, known as mRNA vaccines. It’s faster to create and change these types of vaccines, which is why the vaccine makers can incorporate new protection against omicron variants.

“It’s encouraging that we’ll have these newer versions of the boosters,” Campbell said.

He credits good science and attentive researchers.

“They have paid very close attention to what the virus is doing,” he said. “And one of the advantages of the mRNA technology is that it can be changed fairly quickly to reflect what the virus is doing.”

How do experts know which variants will be dominant in the future?

They do not, Campbell said.

It’s important to know that researchers and vaccines makers must do the best they can to predict which vaccines will be spreading. No vaccine can be a perfect match for the future spread of a virus.

“Under the best case scenario, the best technology is still three months behind,” Campbell said.

Even so, people around the world are lucky that vaccine development is moving much more rapidly than it did in the past. And, it makes sense to have COVID-19 vaccines that protect people from a broad range of variants, not just omicron-specific vaccines, Campbell said.

How do you think the pandemic will continue to evolve? Do you expect COVID-19 infections to increase this fall and winter as they have over the last two years?

The virus that causes COVID-19 is here to stay, Campbell said.

“It’s important to plan for another wave in the fall and winter because there’s a good probability that it will happen,” Campbell said.

“Both vaccine-induced immunity and immunity from natural infection wane over time. We have a virus that’s still here along with waning immunity. And human behavior changes in the fall,” Campbell said. “Kids will go back to school. The weather will be colder. The daylight hours will be shorter, so people will be indoors more and having more contact with other people. Then, we’ll have Thanksgiving, Christmas and New Years and travel associated with the holidays.”

All of those patterns point to the continued spread of COVID-19, he said.

“We have all the ingredients necessary to create a new wave,” Campbell said.

So, he encourages everyone to pay attention to FDA and CDC guidance and to stay up to date on vaccines and boosters.

“These recommendations are based on evolving information that comes from good science,” Campbell said.

“Get your booster per the authorization, whether it’s for everybody or people ages 50 and older. Once it’s authorized, get boosters sooner rather than later so your immunity levels are high by November and December, when all of the conditions for a fall spike are likely to converge.

Editor’s Note: During the pandemic, the Colorado Times Recorder will occasionally post articles, like this one, from UCHealth Today, which is published by UCHeatlh, the hospital associated with the University of Colorado School of Medicine. Our goal is to provide as many people as possible with accurate information about the virus and related topics.