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Get Your Flu Shot: Here’s Why



It’s not too late to get a flu shot.

The vaccine has been available since October, but flu season typically doesn’t reach its height until February. And the season can linger until May.

Is getting a flu shot worth the hassle? Definitely. Consider that influenza killed between 14,000 and 79,000 people in the US every year from 2010 to 2018, according to the Centers for Disease Control and Prevention. And the virus sickened 9 million to 49 million Americans annually during that time.

Flu expert Andrew Pekosz, PhD, answers some common questions about flu shots, why you need a new one every year, and related topics. Pekosz is co-director of the Johns Hopkins Center of Excellence for Influenza Research and Surveillance and a professor of Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health.

I never get the flu. Do I need a flu shot?

Yes. You may have been lucky so far, but you really don’t want to get the flu. It makes you feel miserable. And it kills thousands of people every year.

Another benefit of getting the flu shot: You are less likely to spread the virus to others.

When is the best time of year to get a flu shot?

As soon as they’re ready. In the US, it’s in the fall and the vaccines are usually available in October.

If I didn’t get vaccinated then, should I still get a flu shot?

Yes. Flu season typically doesn’t peak until February so it’s worth getting a flu shot even if you miss the first rollout of vaccines in October.

I heard the flu vaccine is a bad match to the flu viruses this year. Should I just skip this year’s shot?

The flu vaccine protects against three or four virus strains that cause influenza each year. Even if one of the strains is a “bad match,” the vaccine will protect you from the other strains that are out there. 

Will the flu shot make me sick?


Tell me why I should get a flu shot every year. I don’t get one every year for the measles virus.

The viruses targeted by other vaccines behave differently than influenza. You get lifelong immunity from the measles vaccine because the virus doesn’t change much over time.

Flu viruses are quick-change artists. They’re constantly mutating. Every few years, the flu virus changes its outer coat. This makes it hard for the body’s immune defenses to recognize it and attack it.

How long does a flu vaccine protect me?

Vaccination is effective for only six to nine months. The reasons: Flu viruses change so much, and a flu shot doesn’t give you lifelong immunity.

Where can I get a flu shot? Are they free?

With most insurance plans, you can often get them for free at pharmacies and drug stores. You can also get them free at some government health centers. Other sites for vaccination include doctors’ offices and clinics. Check with your local health department for more information.

Should pregnant and nursing women get the flu shot?

The CDC encourages pregnant women to get vaccinated—they should get the flu shot and not the nasal spray flu vaccine. The flu shot is also safe for breastfeeding women.

What about babies?

Children younger than 6 months don’t respond to the flu vaccine. If family members and caregivers are vaccinated, that collective immunity can help prevent the babies from being exposed to influenza.

If the flu kills tens of thousands of people every year, that means the vaccine must not work. Right?

Wrong. Way too many people don’t get the flu vaccine each year. Most severe influenza cases are in unvaccinated individuals.

Why doesn’t the vaccine protect against the right viruses?

It takes a long time to make the vaccine. So, basically we have to decide in March what viruses will be in the vaccine that will be used starting in October.

In the meantime—you guessed it—the virus can change.

Why does it take so long to manufacture flu shots?

It’s a slow process due to the technology used to grow the vaccines. It takes months to produce and test enough viruses for each year’s vaccines.

There must be a faster way.

A lot of researchers are working on a “universal flu” vaccine that could be faster to produce and would protect against many types of flu viruses. Ultimately, they want to produce a flu shot that lasts five years or more. 

Sounds good. When will the universal flu vaccine be ready?

It’s still years in the future. The NIH recently announced a huge multimillion dollar research effort around this. And over the next couple of years, we’ll start to see results from tests in humans. In the meantime, the US government has also launched a study to find ways to improve the current production of flu vaccines.

For more information, check out the CDC’s flu page


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