First, let's agree I'm no doctor. But I do spend a lot of time in the air, and talk to friends who also fly a lot, plus I try to keep up with the latest travel/health information. Let me boil down what I've learned: What to worry about, what not to worry about.
Do worry about a sick seatmate
You've got problems if you have a coughing, hacking seatmate but you don't need me to tell you that. This is actually a time when where a face mask might do you some good, especially if placed over the offending seatmate's nose and mouth. Otherwise, ask your flight attendant if you can be moved, but with so few empty seats on planes due to airline capacity cuts there might not be any place to put you. If there are vacant seats, and you can move even a few rows away, you may escape the germs.
And if you're the coughing, hacking seatmate, think twice about flying. If you look bad enough, a flight attendant might kick you off the plane which happened on a United flight during the height of the H1N1 virus outbreaks.
But say you're seated next to a sick passenger; some say turning on the overhead nozzle and shooting air down in front of your face is helpful. For those of you concerned about cabin air, keep reading.
Don't worry about plane air
I've been talking about the once raging argument over whether airplane air makes you sick as far back as 2007, but most seem to accept that cabin air quality is very good, thanks in large part to today's HEPA (high-efficiency particulate absorption) filters. And remember, the air you breathe on planes isn't "old": Take a look at this Q&A from aircraft manufacturer Boeing:
Q: Doesn't the recirculated air [on a plane] just keep recirculating? A: No. Outside-air mixing replenishes the cabin air constantly. Replenishment assures that the recirculated portion does not endlessly recirculate but is rapidly diluted and replaced with outside air. During cruise or on the ground, the outside air is drawn in at the same rate that cabin air is exhausted out of the airplane. --Boeing.com
Note: Cabin air is dry air, which is why everyone says drink lots of water (and more on that in just a bit). Boeing also says that every single minute of your flight, the ventilation system of an aircraft cabin "supplies about 190 times more oxygen for each person than can be consumed." So go ahead and take a deep breath (as long as you're not next to a feverish flu victim).
Do worry about plane surfaces
I've heard of pilots making fives flights or 'legs' a day on the same plane (sometimes more) so maybe hundreds of passengers have had the opportunity to pass around germs on the plane you're flying on, and when's last time you saw a cleaning crew between flights?
Most dangerous areas of a plane for germs: According to experts and good old common sense, that would be the lavatories, tray tables and aisle seats. That's right, aisle seats: As a sick person makes his/her way to the bathroom, which seatbacks will they be grabbing for support? Think about this when booking a flight during flu system; you may want to re-think your seat selection. The good news is, there are a few things you can do to stay safer. Washing your hands, frequently and well, is number one.
What you don't know about washing your hands
Hand washing may seem incredibly basic but if done right, it can make a difference. And yes, according to the Centers for Disease Control and Prevention, there's actually a right way and a wrong way to do it. Here is the correct procedure as laid out by the CDC:
• Water can be hot or cold as long as it's clean and running. • Make a lather with soap and scrub well including backs of hands, between fingers and under nails. • Continue rubbing hands together for at least 20 seconds or as the CDC says, "Need a timer? Hum the 'Happy Birthday' song from beginning to end twice."
About hand sanitizers: According to the CDC, "Washing hands with soap and water is the best way to reduce the number of germs on them." However, if you don't have access to soap and water, go ahead and use an alcohol-based hand sanitizer but make sure it contains at least 60 percent alcohol. And while hand sanitizers do reduce germs on hands don't be fooled into thinking they'll get rid of all of them. The CDC also wants you to know that these sanitizers are not so effective on hands that are "visibly dirty."
About hand sanitizing wipes: Do have some of these wipes handy, in case you plan on using your tray table; wipe it down thoroughly to reduce germs. Personally, I think I'll just leave mine in the upright locked position.
Staying healthy starts before your flight
If you have a scratchy throat or other signs of illness, see a doctor before you fly. Even if you're feeling fine, remember to eat healthy and get plenty of sleep before traveling: It's a no-brainer way to protect yourself because if you're run-down, you're more vulnerable.
Now back to water again. Hydration helps keep germ-fighting systems like nasal passages in good working order. And like hand-washing, it seems there's a right and wrong way to get hydrated, too: The latest conventional wisdom on the topic suggests that rather than drinking a big bottle all at once and figuring you've done your part, you should sip water throughout your time in the air.
So do bring water aboard your plane but remember to wait to buy it until after passing the security checkpoint so you aren't forced to ditch a perfectly good bottle. Remember, the TSA limits us to just 3.4 ounces of liquid, though you can bring more in a checked-bag.
Now excuse me while I go get my flu shot.