Woman Sneezing at Airport
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The holiday season is fast approaching, and with it will come plenty of air travel. This year, more than six million Americans are expected to take to the friendly skies to get to celebrate with friends and family. But, with all that time in the sky comes one major downside: illness.

Because you're flying through the air in essentially a tin can with minimal ventilation, germs can easily make their way around, causing everything from a cold to a flu. But, how close do you need to be to someone exactly to catch whatever they've got?

According to a study by the Proceedings of the National Academy of Sciences of the United States of America, if you're sitting in the same row as an ill person you're probably going to get sick too.

As the study found, seating within one or two seats of an ill person puts you in the danger zone. But, thankfully, the same study found that if you're three seats away you're likely in the clear, explained.

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"If you are seated further away than a meter from an infected passenger, you are unlikely to get infected during flight," Howard Weiss, a mathematics professor at Georgia Tech and one of the lead authors on the paper, told Popular Science.

To come to its conclusion, Weiss and his team flew on 10 flights between Atlanta and the West Coast. During their travels, Popular Science explained, the team recorded every single interaction passengers had with one another. Though flying can seem like a solitary affair, the team actually found that people interact with one another a lot.

"What most surprised me was that on 10 flights, eight during flu season, only one of 1,500 passengers on 10 flights was coughing," Weiss said. And in total, the team found that people interact an average of 5,000 times on a four-hour flight.

While it seems great that you're not super likely to fall ill, Popular Science did note that these findings can be extrapolated to cover every flight and it doesn't apply to the spread of all viruses, including the nasty ones like measles, a virus that stays airborne for quite some time.

So what should you do to protect yourself from plane germs? According to health coach Natalie Sexton, who spoke to Popular Science, the best way to avoid getting sick is to stay hydrated, eat healthy, and use a tried and true petroleum jelly trick.

"Many infections, including flu germs, can enter through your nostrils," Sexton said. "The best way to minimize this point of entry, especially in a small space, with recirculating air like a plane, is to use a cotton swab to apply a thin layer of petroleum jelly to the inside of your nostrils. An added benefit to this is that it keeps the inside of your nose moisturized and protected from dry heat."