20 Things the Flu Virus Doesn’t Want You to Know

Updated: Mar. 17, 2022

Want to know how to avoid the flu? Here's what the virus would tell you if it could: whom it loves to infect, the surprising places it lurks in your home, and how it makes you feel so crummy.

The flu virus is sneaky

And not just because it’s slightly different each year or that there are about 198 possible subtypes of the virus, reports the Centers for Disease Control and Prevention (CDC). In order to beat the flu this year, you’ve got to get real about it. Knowing how the flu virus thinks can help you stay well this winter.

A woman suffering from cold

Think I’m just a cold? Ha!

Underestimate me at your peril. During the 2017-2018 season, I sent nearly one million people to the hospital, according to the CDC, and had a hand in killing at least 79,000. Not to brag, but I am strong enough to render even a totally normal, healthy person gravely ill.

Doctors hands with injection, doctor with syringe, injection in hospital
Ivan Anta/Shutterstock

I dread nothing more than the flu vaccine

It’s the best way to ensure that I can’t wreak havoc. “The flu vaccine isn’t one of our best vaccines, but it is our only preventative measure,” says Amesh Adalja, MD, senior scholar and an expert in infectious diseases at Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. A vaccine provides your immune system with National Security Agency–level intelligence to identify and eradicate me. In the best of years, it’s 60 percent effective in eradicating me, says Dr. Adalja, but if it can’t stop me, it can slow me down. “Those who get vaccinated are less likely to get severely ill, require a hospital stay, develop secondary pneumonia or ear infections, or die,” he says. Here’s where you can get a flu shot.

Hand in pink protective glove cleaning wooden furniture with rag. Early spring cleaning or regular clean up. Maid or housewife cleans house.

I’m terrified of products labeled “disinfectant”

This means they’ve been tested for their ability to kill viruses (like me). Cleaning products labeled “sanitizer” have to kill only bacteria. Your best bet for killing invaders like me is to use a disinfecting wipe or product and allow it to dry–don’t immediately wipe it off. (Want to prep? Here’s what you should buy for a flu pandemic.)


Merely breathing spreads me

You don’t have to sneeze or cough. Merely talking can spread around tiny droplets that carry us—and we can infect other people a full 24 hours before you exhibit symptoms. Check out these 6 clear flu symptoms that you shouldn’t ignore.

medical weight scale

If you’re obese, you’re contagious longer

If you’re obese, you’re contagious with me 42 percent longer compared to those who aren’t obese, according to 2018 research in The Journal of Infectious Diseases. Because obesity might impact immunity, it may make you contagious for longer. Extra weight may make the flu shot less effective, too.

Businesswoman with a seasonal winter fever and chill blowing her nose on a white handkerchief as she sits in the shadows in her office

You do me a big favor when you’re “too busy” to take a sick day

When you drag yourself into the office, you spread me to your coworkers (awesome) and may make it harder for your body to fight me, so you stay sick longer (more awesome), the National Partnership for Women and Families points out. If everyone had access to paid sick days for the flu, it would keep people home from work and reduce the spread of disease, research shows. (Shudder!) Don’t miss these other ways you’re making your cold or flu worse.

Young woman in pyjama brushing her long dark-blond hair after getting up in the morning; focus on brush!

A good hair day for you is a good day for me, too

And a bad hair day for you is also a good day for me. Despite the belief that I don’t survive as readily in higher humidity, it turns out that I hang out in droplets in the air in both high and low humidity, research shows. (These flu memes will make you laugh when you actually want to cry.)

close-up partial view of african american man washing in bathroom
LightField Studios/Shutterstock

Thanks for skimping on handwashing

Next to the flu vaccine, good hand hygiene is one of your best defenses against me. If my viruses linger on your hands and then you touch your eyes, nose, or mouth (trust me, you do this a lot), we get easy access. Be sure you have these 12 things in your DIY flu-fighting kit, too.

Tamiflu, the medication to target the H1N1 swine flu.

Is that Tamiflu you’re taking?!

Antiviral drugs are my biggest enemy once I’ve succeeded in infecting you. “With any infectious disease, the earlier you start treatment, the better,” says Dr. Adalja. Lucky for me, though, there’s only a brief ideal window in which to use these medications. They are most effective if you take them within the first 48 hours of having flu symptoms, he says. If you wait too long, I can still run rampant.

Sick boy with thermometer laying in bed and mother hand taking temperature. Mother checking temperature of her sick son who has thermometer in his mouth. Sick child with fever and illness in bed.

I love children

They are my biggest spreaders. Kids’ immature immune systems require a week or two to fight me, giving me ample time to reach others. Children are also delightfully unhygienic. If I infect one child, I likely gain entry to that child’s immediate family and many of his or her classmates. Don’t look now, but these 17 natural remedies for colds and the flu really work.


I can live out in the open for hours

Most of you probably don’t know that I can live for up to two days—48 hours—on hard surfaces like doorknobs, keyboards, and elevator buttons, just waiting for you to come along.

Sick and tired black woman lying in the bed

I love it when you sneeze into your hands

You may think this is a great way to save the folks around you from infection, but the truth is, unless you wash your hands immediately, you’ll transfer a bunch of my viruses to the very next thing you touch. That’s why the CDC recommends that you cough or sneeze into a tissue or the crook of your arm instead. Definitely don’t bother checking out 14 other things you shouldn’t do if you have the flu.

Side view of sick woman having coffee on sofa in living room

I’m extremely contagious

Ever wonder how and why I’ve caused so many epidemics over the centuries? Because I’m very, very, very contagious. Not only can people spread flu viruses around a full day before they start feeling sick, but the infected stay contagious for five to seven days after becoming sick, according to the CDC. Now, that’s stamina.

Glass bottle of white pills
Alexander Khoruzhenko/Shutterstock

Antibiotics won’t do a thing to me

I know it’s tempting to ask your doctor for antibiotics when you feel terrible, but they only work on bacteria, not viruses, says Dr. Adalja. So for my sake, go ahead and ignore these 11 ways to treat the flu.

Healthy concept: Stethoscope and electrocardiogram (ECG, EKG).

I can trigger heart attacks

When I infect you, I don’t just irritate your chest and sinuses—there’s also widespread inflammation all over your body. And that inflammation can increase the risk of developing blood clots that triggers a heart attack, according to a study in The New England Journal of Medicine.

Doctor injecting vaccination in arm of asian little child girl,healthy and medical concept

You should get vaccinated by the end of October for best protection from me

But it’ll help protect you from me even if you get the flu shot much later than that. The flu vaccine takes about two weeks to become effective, so if you’re trying to avoid getting sick, doctors say it’s ideal to get jabbed early on in flu season—by the end of the October. But I’d prefer it if you didn’t learn these 10 secrets doctors use to avoid getting sick.

Vaccines and syringes
panpilai paipa/Shutterstock

I change every year

Flu viruses come in all different strains—with names like H1N1, H3N2, and B/Colorado. And every year there’s a different group of us making the rounds. That’s why a new vaccine has to be made every year, to target us newbies. Find out which flu is worse, a or b?

Doctor Examining old Patient's Ear

I can cause some pretty bad complications

After causing all the usual symptoms (fever, headache, cough, body aches), I can also lead to pneumonia, sinus infections, and ear infections. Some people are more vulnerable to my dastardly deeds than others, including seniors, pregnant women, kids under five years of age, and people with chronic health conditions like asthma or diabetes. Learn the difference between cold and flu.

texture of white mist on a black background to overlay

I can fly!

Well, not exactly. I get around in tiny droplets of moisture that get out into the air when you breathe, talk, cough, or sneeze. Here’s the craziest part: These droplets can travel six feet.

Cold and flu. Sick woman caught cold, feeling illness and sneezing in paper wipe. Closeup of beautiful unhealthy girl covered in blanket wiping nose and looking at thermometer. Healthcare concept.

I was one of the original “influencers”

You’ve heard about all those social media influencers on Instagram? Well, my full name—influenza—comes from the Italian word for “influence.” After four major worldwide pandemics, I’ve earned it. Each year, an average of 3 to 11 percent of the U.S. population contracts the flu virus. Now check out 15 surprising ways to prevent colds and flu.