Flu shot FAQs: Myths and facts

This piece is sponsored by Sanford Health.

By Dr. Avish Nagpal

As a physician and specialist in infectious disease, each fall I prepare and advocate for all my patients and colleagues to get a flu vaccine.

And every year, there’s some skepticism or misconceptions that I try to dispel.

Here are some commonly asked questions about influenza and the flu vaccine that you may have too:

If I haven’t gotten the flu before, do I need to get a vaccine? Why?

Yes, absolutely — for the same reason you put your seat belt on every time you drive, even if you haven’t had an accident.

The flu season can go until late spring — should I wait to get my vaccine?

No, you should get your vaccine as soon as they’re available. The flu season begins in October, and during the past couple of years, we have seen early peaks in November and December.

As with any vaccine, it will take about two weeks to reach maximum antibody response, so getting vaccinated early in the season gives your body enough time to develop or boost your immunity.

If I got a flu shot last year, do I need to get one this year too?

Yes. There are constant changes in the circulating strain of the influenza virus, so getting vaccinated every year with the updated vaccine is highly advised.

Does the flu shot prevent me from getting the flu?

Some vaccines are excellent at preventing disease altogether. For example, it’s very unlikely you will get measles if you have received the MMR vaccine. Other vaccines make diseases milder. The flu shot and COVID-19 are good examples of this. Not all strains of the flu are in the vaccine, so there’s still a chance you may contract influenza even if you’ve been vaccinated. However, we shouldn’t let perfect get in the way of good. Vaccination isn’t solely about prevention. While the flu shot may not prevent you from getting the flu, it’s less likely you will have serious complications or need hospitalization if you do contract the flu.

This is particularly important for people who are at an increased risk for complications of the flu, including those who are very young, very old, overweight or immunocompromised. The flu is a potential killer to those at risk for complications.

I’ve heard about flu vaccines containing thimerosal. What is it?

Thimerosal is a preservative used in some vaccines and other drugs to prevent the growth of harmful microbes. While significant research shows it to be safe, many vaccines are available without this preservative. The flu vaccine offered at Sanford Health does not contain thimerosal.

Are there side effects or risks of getting a flu shot?

There are some minimal possible side effects of a sore arm, mild achiness, perhaps very low-grade fever.

You can’t get the flu from the flu vaccine — just like you can’t get tetanus from a tetanus vaccine or hepatitis from a hepatitis vaccine.

I’m generally healthy and have gotten over the flu before — do I still need a vaccine?

Yes. There are multiple strains of influenza in circulation, and new strains are constantly emerging. Just because there was recovery from one strain in a particular year does not mean that future bouts of flu will not be catastrophic.

Influenza is a natural pathogen of both healthy and not-so-healthy individuals. Anyone can come down with severe illness because of the flu, which may lead to life-threatening complications such as pneumococcal and staphylococcal pneumonia, needing hospitalization for oxygen support and fluids, and even requiring to be put on a ventilator for life support.

I’m pregnant — should I get a flu shot?

Absolutely. Pregnancy has been identified as its own category for increased risk for flu complications like those I mentioned.

I’m breastfeeding — should I get a flu shot?

Absolutely. It will help prevent the flu from being transmitted to your very vulnerable young child, and you will pass on protective antibodies to your newborn whose immune system is still not mature enough to fight off many of the common infections.

What if I have other questions about influenza or getting vaccinated?

Talk to your primary care doctor about any concerns you have. The Centers for Disease Control and Prevention website also has a wealth of information.

What does the flu vaccine cost? Where can I get it?

Most insurance plans cover the cost of the flu vaccine, which is widely available at physician offices, pharmacies and schools.

Get vaccinated as soon as possible. It could save your life and help protect the people you love.

Find out more about the flu shot at Sanford Health.

Learn more

• For chronic illness patients, flu shots even more important
• Why do we get sick more in the winter?
• Your 10 most Googled questions about the flu and flu shot