Last year’s flu season was exceptionally mild, despite its convergence with the COVID-19 pandemic. Will the 2021-2022 flu season be a repeat? Or will we have the flu-meets-COVID “twindemic” many feared last year?

“The only thing we can predict about influenza each year is that it's going to be unpredictable,” explained Sarasota Memorial Infectious Disease expert Manuel Gordillo, MD.

“Last year, prevention measures like mask-wearing and social distancing were often mandated and widely used, so we had no influenza. It was incredible,” Dr. Gordillo said. “Influenza is a lot less contagious than COVID, and it’s easier to control by these non-pharmacologic measures.”

But this year, as we head into the October-to-May flu season, many people have relaxed or stopped using the behavioral prevention measures that minimized flu infections last season.

“I believe we are at higher risk this year from influenza and having that twindemic convergence of the 2 viruses, especially now that schools are open,” said Dr. Gordillo. “Children are definitely the ones who carry influenza and take it to their households.”

Influenza cases in our community are still very low, but flu is being monitoring carefully, especially as we move into what’s typically considered the start of flu season.

Avoiding Illness, Preventing a ‘Twindemic’

Your best chance to avoid getting sick with the flu is by getting an annual flu shot. And our community’s best shot at preventing a twindemic is widespread vaccination for COVID-19 and seasonal influenza.

“Prevention, as we know, is always better than treating something,” said Dr. Gordillo. “No matter what, prevention always wins.”

Everybody older than 6 months should get a flu shot, with few exceptions, and those age 65 and older should get a high-dose flu vaccine. Everyone 12 and older should get a COVID-19 vaccine, with few exceptions: The Pfizer COVID-19 vaccine (Comirnaty) is approved for everyone age 12 and older, while the Moderna and Johnson & Johnson (Janssen) vaccines are authorized for ages 18 and older.

With some people now getting COVID-19 vaccine third doses — or even first and second shots — and others anticipating getting an approved COVID-19 booster shot soon, many have questions about the safety and timing of getting flu and COVID-19 shots. 

Below, Dr. Gordillo addresses these questions and concerns about seasonal flu, COVID-19 and vaccinations.

Flu Shots & COVID-19 Vaccinations

Is it safe to get a flu shot and a COVID-19 shot at the same time?

Yes. 

Updated guidance from the Centers for Disease Control and Prevention (CDC) affirms that it’s safe to get the COVID-19 vaccine and influenza vaccine at the same time. However, when co-administered, the two shots should be given in separate anatomical sites: You can get one in the right arm and the other in the left arm at the same time.

The recommendation is the same for everybody, including those who are immunocompromised.

Is there a recommended wait time for getting other inoculations (pneumonia, HPV, shingles, etc.) and the COVID-19 vaccine?

With the exception of flu shots, the CDC currently advises a 2-week waiting period between getting a COVID-19 vaccine shot and other vaccines. But this may change.

The CDC is still reviewing data regarding co-administering the COVID-19 shot with other vaccines (except the flu). Updated guidance on this is expected in the next few weeks. This would include age-recommended vaccines for children, HPV vaccine shots, and pneumonia and shingles vaccines, among others.

Is there a recommended wait time for getting the flu shot after receiving a monoclonal antibody infusion?

No.

The antibody in Regeneron's monoclonal antibody therapy is very specific to the spike protein of SARS-CoV-2 (the virus that causes COVID-19). It will not attack any part of the influenza vaccine.

However, recipients of monoclonal antibody therapy should wait 90 days after treatment to get a COVID-19 vaccination.

Flu vs. COVID-19: Diagnosing & Treatment

Based on symptoms, will we be able to tell whether we’re sick with COVID-19 or the flu?

No. 

Both are contagious respiratory viruses, and they have similar symptoms, so it's going to be difficult to differentiate between 2 viruses like that circulating at the same time. And there are other respiratory viruses to consider, like parainfluenza, RSV and rhinovirus.

The only way to know what’s making you sick will be to do a test. 

If I develop flu- or COVID-like symptoms, what should I do? 

Always test if you develop symptoms. 

You’ll want to know whether you have COVID-19 or flu because treatment will be very different. Each virus has different implications for how you should interact with others — COVID-19 is more contagious — and how long you’d need to quarantine.

For flu, you’ll want to know as quickly as possible, so you can be prescribed an early course of anti-viral, like Tamiflu, to reduce the duration of the illness.

On the other hand, if you have COVID-19, early detection may allow you to qualify for monoclonal antibody treatment. You’ll also need to isolate or quarantine for longer. 

You can use an at-home test for COVID-19, but those kinds of self-test kits aren’t available for flu. If you test negative for COVID-19, you’ll want to get tested for influenza through your physician, a clinic or an urgent care center where tests are offered. 

Have a question for an SMH expert? Email it to AskAnExpert@smh.com.

Infectious Disease specialist Manuel Gordillo, MD, leads Sarasota Memorial’s Infection Prevention and Control Department and has been on Sarasota’s frontlines of the COVID-19 pandemic from Day 1. He is board certified in Internal Medicine and Infectious Disease.

** NOTE: Information above was published Sept. 21, 2021. For the latest updates on COVID-19 and vaccines, we recommend visiting the CDC website.