Germs on a plane are far likelier to get under your skin than snakes, screaming babies and or smelly seatmates, and they're most common on a surface that is touched frequently during a typical flight, a new study found.
Travelmath.com recently sent swab-carrying microbiologists to five airports and onto four airplanes and asked them to determine which surfaces were the dirtiest.
The results will make you reach for the hand sanitizer and rethink what you touch when you travel.
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Aircraft back-of-seat tray tables, which travelers have been known to use as a platform for everything from eating a meal to changing their baby's diapers, are the germiest surfaces on airplanes by far, the experiment found. They were followed in descending order by the overhead air vent, the lavatory flush button and the seat belt buckle.
Median testing results for the four flights swabbed, reported in colony-forming units (CFUs) per square inch, found 2,155 CFUs on tray tables, 285 CFUs on the overhead air vent buttons, 265 CFUs on lavatory flush buttons and 230 CFUs on seat belt buckles.
"Airline staff are under more pressure in recent years to quickly de-board arriving flights and board departing flights to maximize profit for their carriers," the study notes, "…so tray tables are often only cleaned at the end of the day."
In airports, the microbiologists identified drinking fountain buttons and bathroom stall locks as the dirtiest places, with 1,240 CFUs and 70 CFUs per square inch respectively.
Grossed out yet?
For comparison, tests done by the National Science Foundation found that pet food bowls in homes have 306,000 CFUs per square inch, while home toilets have 172 CFUs and cell phones have 27.
John Zautcke, medical director at the Chicago O'Hare medical clinic, which is opening its first seasonal, in-airport flu shot clinic this weekend, said airports and airplanes are not dirtier than homes or other public places.
"Airports and airplanes get cleaned, but there are hundreds of thousands of people moving through those spaces every day," he said.
It is impossible to avoid coming in contact with the germy places on airplanes and in airports but Zautcke says that's no reason to stop traveling.
To avoid catching a cold or the flu from germs left behind by other travelers, "use common sense," says Zautcke, "Try not to touch your mouth after touching any of the germy places on planes and in airports. Wash your hands a lot. Bring along hand sanitizer. Use a towel to open the lavatory door and carry a small package of towelettes."
Zautcke suggests using a hand sanitizer after buckling or unbuckling your seatbelt on the plane and wiping down the tray table before using it.
And what about the strange looks you may get from a seatmate?
"There is no reason to be ashamed or embarrassed," said Zautcke, "The important thing is to try to avoid germs and stay healthy. In fact, it would be polite to offer your seatmate some sanitizer as well."