It’s flu season, and here’s why you should get your flu shot this winter

Flu vaccine
Medical assistant Lim Ros prepares to administer a flu vaccine at Central Pediatrics in St. Paul on Oct. 25, 2011.
Nikki Tundel | MPR News 2011

Flu season is upon us. Experts warn that with the highly contagious delta variant circulating, it is important to protect communities not just from the coronavirus, but from the flu, too. They encourage everyone to get the flu shot, and to prevent infection spread by hand-washing, wearing masks in public spaces, and isolating when feeling ill.

As many people are planning travel and gatherings this holiday season, here are tips and advice from public health experts to help mitigate infection risks and prepare for the flu during our second pandemic winter.

Click a question below to jump to a section.

What is the flu?

Influenza is a highly contagious respiratory virus, causing mild to severe illness. People can die from the flu, especially individuals who are older or immunocompromised, said Dr. Priya Sampathkumar, a leading infectious disease specialist at Mayo Clinic in Rochester, Minn. Pregnant women are also at an increased risk for developing severe illness, she said.

Why do I need a flu shot every year? If I had the flu last year, or if I got a flu shot last year, am I still protected this year? 

No. We need a new flu vaccine each year because the flu virus changes every year. The vaccine must change along with it for optimal protection.

“It’s not unusual to see 30,000 to 50,000 deaths a year from influenza,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “If we have a major flu season, it will be too late for you to get your shot when that really hits us hard. So now's the time to get your vaccination.”

Can I get a flu shot alongside a COVID-19 booster?

Yes. You can get a COVID-19 vaccine, or a booster alongside your flu shot.

How does the flu virus spread? Are there any high-risk activities I should avoid? How can I prevent infection?

“All the things that increase your risk of getting COVID also increase your risk of getting influenza, so being unmasked in a crowded place is probably the most risky activity,” said Sampathkumar. Crowded, enclosed spaces like airports come with higher infection transmission risk, she said, so travelers should wear masks and get their flu shots.

“COVID is still pretty rampant around the country. So, wear a mask, avoid touching your mask with your hands, and carry hand sanitizer with you, so you can keep your hands clean when you're traveling,” Sampathkumar said.

She said the flu virus can live on surfaces, like doors or tabletops, for a couple of hours. Touching a surface and then touching your eyes, nose or mouth without using hand sanitizer in between can lead to an infection.

If I have the flu, could I be contagious before I feel sick?

Yes. Those infected with the flu virus are contagious 24 hours before the onset of symptoms.

What are the most common flu symptoms?

The most common flu symptoms are fever, fatigue, runny nose and sore throat. Young children can have diarrhea, though Sampathkumar said it is uncommon in adults.

If I feel sick with flu-like symptoms, what should I do?

If you feel sick with flu-like symptoms, you need to get tested both for COVID-19 and the flu, and stay home to limit infection spread.

Is it the flu or COVID-19? How can I tell the difference?

You can’t. It’s difficult to differentiate between COVID-19 and the flu based on symptoms alone, said Sampathkumar. Even if you have been vaccinated for COVID-19 and the flu, you still need to get tested for both if you feel sick. Breakthrough COVID-19 infections are possible, and effectiveness of the flu vaccine varies every year. 

“What the flu vaccine does is it keeps you from getting very ill and needing hospitalization or needing a ventilator,” Sampathkumar said. “You still could get influenza.”

Can I get COVID-19 and the flu at the same time?

Yes, “having one doesn’t mean you don’t have the other,” Sampathkumar said.

She said any illness can make a person more vulnerable to contracting other illnesses, so it’s important to get the COVID-19 vaccine and the flu shot.

Is the flu expected to be more severe this year than it was last year?

That is difficult to predict, Sampathkumar said. While last year’s flu season was mild, she is concerned that as people are more relaxed about masking and other COVID-19 safety guidelines this year, flu activity could be problematic for hospitals already overwhelmed by the current delta surge. 

“Even a relatively mild flu season could be really a big problem for hospitals that are so full right now because in an average year, we do see people who need hospitalization for influenza,” she said, “and right now hospitals are so full that we can't really afford to have people get sick with influenza on top of everything else that's going on.”

Who should get the flu shot?

“So because of the fact that it's very infectious, and it can have very bad outcomes, we recommend that everyone get the flu vaccine,” said Sampathkumar. Anyone over the age of 6 months can get vaccinated against influenza. Children under 9 who have never received the flu shot before will need two doses, separated by about four weeks. For everyone else, one shot is sufficient.

What if I have allergies?

There are different options, and the vaccine is made with such small amounts of egg that it is not a major concern for those with allergies. For those who are still concerned, the vaccine without any egg is also available, Sampathkumar said. Those who want or need an alternative can get a nasal spray instead of an injection.

Getting FluMist at Children's Hospital.
Leo Moulsoff receives a FluMist at the Children's Hospitals and Clinics of Minnesota on Dec. 15, 2014 in St. Paul.
Yi-Chin Lee | MPR News 2014

Can my child get the flu shot? Can they get vaccinated when they have a cold?

Yes, children can get the flu shot even if they have a cold. It will still be safe and effective. If they have a runny nose, they should get the shot instead of the nasal spray.

Flu shots at Children's Hospital
Children's Hospitals and Clinics of Minnesota Medical Assistant Brittany Williams gives a flu shot to Oliver Sherman, almost 12 months old, on Dec. 15, 2014 in St. Paul. Oliver's parents took him to receive the flu shot before traveling and visiting family during the holidays.
Yi-Chin Lee | MPR News 2014

How long does it take for immunity to build after getting the flu shot?

It takes about two weeks for the body to build immunity after getting the flu shot.

Does the flu shot have any side effects?

You might have a sore arm, muscle aches or a low-grade fever for a day or two after getting a shot. The vaccine cannot make you sick and for most people, side effects are “very, very minimal,” Sampathkumar said. “You feel the needle going in, you may have a little bit of local tenderness at the site, but that’s about it.”

Where can Minnesotans go to get their flu shot and how much does it cost?

Minnesotans can get the flu shot at their doctor’s offices, pharmacies and clinics.

A flu shot usually costs about $20, but it should be fully covered by insurance, and many health departments offer the shot for free, Sampathkumar says.

Flu shot
A nurse practitioner prepares a seasonal flu vaccination for a patient at a clinic on Sept. 1, 2009, in Chicago.
M. Spencer Green | AP Photo 2009

How are flu outbreaks tracked in Minnesota?

Public health workers track outbreaks in larger institutions like nursing homes and schools. “When people come into certain clinics or laboratories around the state, viruses are forwarded on to the Minnesota Department of Health,” said U of M’s Osterholm. 

Testing is then performed to determine the type of flu virus circulating. That tracking and testing is used to make recommendations to the public about their flu shots, he said.

Will I have to keep getting the flu shot every year, forever?

For now, yes. But in the future, maybe not.

The Center for Infectious Disease Research and Policy at the University of Minnesota leads global public health collaboration for an initiative called the Influenza Vaccines Roadmap. Right now, we depend on vaccine technology developed in the 1940s, Osterholm said. We need to get a flu shot every year, for every new flu season. In the future, he hopes that can change with the development of a new vaccine that provides long-term, high quality protection against the flu.


Do you have more questions about getting a flu shot this year? Let us know!

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