Updated

Whether you decide to get a flu shot this year or not, it's important to take steps to prevent yourself from getting the seasonal flu.

If you already sneeze into your sleeve, wash your hands diligently, and avoid crowds where these viruses can easily spread, you're on the right track. But you still may be putting yourself at risk in these unexpected ways—probably without even realizing it.

[sidebar]

1. Worrying too much
Panicking about getting sick can make you just that—sick. Research shows that anxiety can manifest itself in a wide variety of ailments—including acid reflux, insomnia, skin rashes, and depression—so it shouldn't be surprising that the added stress of worrying about coming down with something can also weaken your immune system and leave you more vulnerable to catching a bug.

2. Hugging, kissing, and shaking hands
What's so dangerous about a simple handshake? Close contact with infected individuals is one of the easiest ways to pick up a virus. That doesn't mean you should be antisocial all flu season long, but you should be aware of possible transmission opportunities. If you are in a situation where physical hellos or good-byes are necessary, try not to touch your mouth or eyes afterward until you can wash your hands.

The Centers for Disease Control and Prevention (CDC) recommends maintaining a 6-foot buffer from sick people to cut down on the virus's ability to spread. So, as a precautionary measure, all sorts of cultural greetings—from shaking hands to hugging to kissing on the cheek—are getting the ax.

3. Smoking
Smoking cigarettes weakens the tiny disease-fighting hairs tucked inside nasal passages and the lungs, which trap and dispose of germs. This can leave your body more susceptible to attack.

Dr. Pascal James Imperato, the dean of the School of Public Health at SUNY Downstate Medical Center, in Brooklyn, warns that prior lung damage, such as that caused by smoking, can leave you at greater risk of serious complications as well.

"Chronic smokers are always much more vulnerable to severe viral infections of the respiratory type," he says. "They have damaged lungs, so they are more susceptible to coming down with illnesses and developing pneumonias following them."

4. Hitting the gym
Some behaviors that in moderate amounts keep you healthy can actually weaken your immune system when taken to the extreme. For example, overexercising can leave your body struggling to cope with added physical stress—especially if you're not sleeping, hydrating, and fueling your body adequately. Unfortunately, the gym is also a great place to pick up viruses, from the sweaty treadmill to the benches in the locker room; plus, germs likely even catch a ride home on your gym bag.

We're not saying you should skip out on exercise: When done right, it will keep your immune system strong against the flu. But to protect yourself, wipe down machines before using them and take your own mat for stretching—or cover a borrowed one with a towel. Shower with soap and water immediately after working out to help kill any germs you may have been exposed to.

[pullquote]

5. Drinking alcohol
You may want to reconsider that night on the town during the height of flu season: You could wake up the next day with something much worse than a hangover. A study in BMC Immunology found that mice who consume large quantities of alcohol in a short period of time are left with weakened immune systems and might have a harder time fighting off infections for at least 24 hours.

Another side effect from drinking too much: Alcohol can quickly and easily dehydrate you, which interferes with your nose's and throat's ability to trap germs and expel them in the form of mucus.

6. Relying solely on antibacterial hand gel
First, check the ingredients in your hand sanitizer: It should contain ethanol, or isopropanol, to work best. (If alcohol-based sanitizers are not available to you or not allowed in your workplace, alcohol-free products may also be helpful, the CDC says.)

Second, don't replace old-fashioned hand-washing. Using soap and water is still your best bet to washing away the flu. And if you are washing your hands correctly, says John M. Barry, author of The Great Influenza, ordinary soap will do the trick.

7. Washing hands incorrectly
Too many people are not washing their hands correctly, despite all the advice to get scrubbing. The U.S. earned a measly B- on a report card that was issued by the Soap and Detergent Association based on the results of an independent telephone survey. Frequent hand-washing, as often as 10 times a day, is one of the most recommended defenses against the flu, but 39 percent of respondents seldom or never wash after coughing or sneezing. And almost half of the respondents who do wash only do so for 15 seconds or less, despite recommendations to wash for 20 seconds or more.

Whistle "Happy Birthday" twice while scrubbing all surfaces on hands and between fingers, and dry hands completely. Turn off the faucet and open the bathroom door with a paper towel to keep hands clean.

8. Mishandling a face mask
Face masks are generally not recommended by the CDC in normal home or occupational settings. But some people still choose to wear them, especially if they are at high risk of flu complications or are regularly exposed to sick people—and recent research has shown that the masks do seem to help prevent the spread of flu.

If you're going to wear a mask, make sure you're using it, and removing it, correctly—or it's bound to do you little good. "Masks accumulate the virus," says Barry. "You'd have to be extremely careful taking the mask off. Make sure the mask doesn't brush against your nose or mouth or eyes; throw it out, and definitely wash your hands after." Remove the mask by the straps or strings in the back so you avoid touching the front of the mask, which will be the most contaminated.

9. Taking flu drugs prematurely
In the past, some patients have rushed to stock up on antiviral medications like Tamiflu. The majority of people won’t need these drugs—ever—and taking them unnecessarily could increase the risk that the virus will become resistant to these medicines.

On a related note, parents who are prescribed liquid Tamiflu for their children could accidentally give sick kids the wrong amount, warns a letter on the New England Journal of Medicine website, because dosage instructions don't always coincide with measurement markings on the syringe that comes with the medication. Anyone prescribed Tamiflu should discuss with a doctor why he or she is a good candidate for this medication, and make sure they understand the correct dosage instructions.

10. Worrying too little
This may seem to contradict risk factor No. 1, but, in fact, the healthiest approach to flu season is to take a position somewhere between panic and indifference. You may assume that you're too young or too healthy to get very sick from influenza. That is still probably true—though maybe not as true as in previous years.

The bottom line: Age group or health status doesn't make you invincible, and we should all take flu prevention seriously.

This article originally appeared on Health.com.