Get a Flu Shot Now or Wait?

This year, experts are recommending you get vaccinated in September or October to guard against an early, and possibly nasty, flu season.

Medically Reviewed
There should be plenty of flu vaccines available this year to help fend off a possible “twindemic” of flu and COVID-19.Everyday Health

If you typically wait until Halloween or maybe even Thanksgiving to start thinking about getting your flu shot, you may want to rethink your vaccination game plan for this year.

While the flu barely caused a blip last season, thanks to COVID-19 precautions like stay-at-home orders, masking, and social distancing, experts say that's not likely to be the case for the 2021–2022 flu season.

With children returning to school and adults going back into offices, doctors are expecting to see a significant uptick in flu cases this fall and winter.

In fact, last winter’s lack of flu may have set us up for a particularly early, and potentially severe, flu season, says the Centers for Disease Control and Prevention (CDC).

“Even in years when you don’t catch the flu, you are still often exposed to it,” explains Eili Klein, PhD, an associate professor of emergency medicine at Johns Hopkins Medicine in Baltimore and a fellow at the Center for Disease Dynamics, Economics, and Policy in Washington, DC.

“That exposure helps your immune system make antibodies that ‘remember’ the virus and how to attack it,” he says.

Because there was so little flu activity last season, people (particularly those who didn’t get last year’s flu vaccine) won’t have that immunity boost. This could leave us more vulnerable to contracting the flu this year, Klein adds.

Indeed, as flu returns this fall — and delta or other new coronavirus variants continue to circulate — we could possibly be looking at a “twindemic” of flu and COVID-19.

Ready to roll up your sleeve? Here are answers to a few common questions about getting the vaccine.

Ernest Grant, PhD, RN, on Flu Shot Truths & Myths

Recorded 10/01/20. Ernest Grant, PhD, RN, joins Pamela Kaufman in discussing facts and myths about the flu shot, and how the flu may affect people during the COVID-19 pandemic.
Ernest Grant, PhD, RN, on Flu Shot Truths & Myths

When’s the best time to get a flu shot?

September, or even October, may seem a little early to get your flu shot, but it’s really not, says Frederick Chen, MD, MPH, chief of family medicine at Harborview Medical Center and professor of family medicine at the University of Washington School of Medicine in Seattle.

He recommends getting the vaccine as soon as it’s available, preferably before the end of October. “Trying to ‘time’ the vaccine can be a distraction,” notes Dr. Chen. “The most important thing is just to get it.”

The flu vaccine keeps millions of people from getting the flu, having to go to the doctor or hospital, or even dying.

It’s estimated that during the 2019–2020 flu season, the flu shot prevented estimated 7.5 million influenza illnesses, 3.7 million flu-related medical visits, 105,000 flu-related hospitalizations, and 6,300 influenza-related deaths, according to the CDC.

RELATED: Is a Flu Shot Breakthrough on Its Way?

If you get the flu shot too early, can it wear off before flu season is over?

There is some truth to the concept that the flu shot can lose its effectiveness over time, says Chen. “In general, we don’t recommend people getting the flu shot in July or August,” he adds. “It’s a good idea to wait until the middle of September.”

Given that this year there will be a greater number of susceptible people, coupled with kids going back to school, the flu could potentially peak earlier than usual, notes Klein. “I wouldn’t recommend waiting until late November to get the flu shot,” he says.

Although some lab tests have suggested that the vaccine’s effectiveness might fade after six months or so, there is a lot of individual variability, says Stuart Ray, MD, an infectious disease physician at the Johns Hopkins Hospital in Baltimore.

Plus, even if the vaccine wears off a bit, “you will still have immune ‘memory’ that will reawaken and contribute to protection against a severe infection,” he explains.

Can I get my flu shot and a COVID-19 vaccine in the same visit?

Yes, people can now receive a COVID-19 vaccine (including a booster shot, if and when you’re eligible) and the flu shot during the same visit, says the CDC.

Previously, the CDC had recommended getting your COVID-19 shot at least two weeks before or after any other vaccinations. But that guideline was made out an abundance of caution when the COVID-19 vaccines were new, says the agency. Spacing out the vaccines is no longer considered necessary.

Theres hardly any flu in my area right now. Can I wait to get my flu shot?

You shouldn’t wait until flu activity is high in your community before you get a shot, says the CDC.

While there may not be any cases of flu in your area right now, the virus can start spreading at any time.

Keep in mind, too, that you don’t become immune to the flu as soon as you get the shot. Your body takes about two weeks to develop antibodies that protect against flu.

Ideally, you should get vaccinated against flu by the end of October so you’re protected once the flu arrives in your community.

Should I be worried about a shortage of flu shots?

Currently, the CDC isn’t anticipating any shortages or difficulty getting a flu shot this season.

Flu vaccine manufacturers are projecting that they will supply the United States with as many as 188 million to 200 million doses of influenza vaccine for the 2021–2022 season, which should be sufficient.

Is it ever too late to get the flu shot?

It’s never too late to get a flu shot, says Chen. As long as flu viruses are still circulating, it’s still worth getting a flu shot, even if it’s February or March.

“Especially this year, you should get a flu shot as soon as you can. But if for some reason you wait until later in the season, you should still get it,” he adds.

A pharmacy or grocery store can be a fast way to get a flu shot. But are places like these safe?

Yes, it’s perfectly safe to get your flu shot at your local pharmacy or grocery store, provided the workers and nearby patrons are following COVID-19 safety guidelines, says Chen.

CVS Pharmacy, for instance, offers flu shots for walk-in patients or by appointment, and ensures safety with the following precautions:

  • All staff, patients, and outside customers must abide by physical distancing guidelines.
  • Pharmacists wear masks, gloves, and face shields.
  • Patients are required to wear face coverings and answer COVID-19 screening questions.

The more convenient getting a flu shot is, the more people will get one, Chen adds. VaccineFinder can show you locations in your area that offer flu shots.

RELATED: Where to Get a Flu Shot

Should anyone not get a flu shot?

According to the CDC, virtually everyone should get a flu shot. The only exceptions are:

  • Children under 6 months of age.
  • People who have severe, life-threatening allergies to the flu vaccine or any ingredients in the vaccine. This may include gelatin, antibiotics, or other ingredients. Severe allergic reactions to flu vaccines are very rare.
  • People with an egg allergy should consult with their doctor for information about the flu vaccine. Most people with an egg allergy can get a flu shot, and there are vaccine formulations that are egg-free.
  • Some people who have had a rare disorder called Guillain-Barré syndrome (GBS) should not get a flu vaccine and should discuss their situation with a doctor.

I’ve heard some things that make me hesitate about getting a flu shot, like getting a flu shot can give you the flu. Should I worry?

Most years only about half of Americans get flu shots, notes Chen. “The most common reason that I hear about why people don’t want a flu shot is that they got a flu shot once and got the flu afterward,” he says. “Let me be clear: Flu shots do not give you the flu.”

There are a few reasons why someone might feel like they’ve gotten sick because of the shot.

“Some people may experience flu symptoms after being vaccinated because they become ill from different respiratory viruses such as rhinoviruses, which are associated with the common cold,” he says.

It’s also possible to become ill with the flu shortly after being vaccinated because it takes up to two weeks for the body to develop immune protection after the shot, notes the CDC.

Flu vaccines do vary in how well they work, so it’s also possible for people who are vaccinated to still get sick. Even if that happens, however, research shows that the vaccine can still help by reducing the severity of the flu in people who got the flu in spite of having been vaccinated.

One study published in the journal Vaccine, for example, found that among adults hospitalized in New Zealand from 2012 to 2015 with the flu, vaccinated patients were 59 percent less likely to be admitted to the ICU than those who had not been vaccinated.

The people who did end up in the ICU with the flu spent an average of four fewer days in the hospital if they had received the flu shot compared with those who didn’t.

RELATED: 7 Flu Shot Myths You Should Stop Believing

Can getting a flu shot increase your chances of getting COVID-19 or another respiratory illness?

There is no evidence that getting a flu shot increases your risk of getting COVID-19 or other upper respiratory tract infections like the common cold (caused by a different type of coronavirus), states the CDC.

If you’ve heard rumors on social media to the contrary, it may be due to a study published in January 2020 in the journal Vaccine, which found an association between the flu vaccine and four commonly circulating coronaviruses (but not the one that causes COVID-19). The study design was later found to be flawed.

Another study, published in May 2020 in the journal Clinical Infectious Diseases, failed to find any connection between the flu vaccine and increased risk of infection with other respiratory viruses, including seasonal coronaviruses.

The majority of published research to date suggests that the flu vaccine does not make people more susceptible to other respiratory infections.