When Hillary Bessiere flew to Cancun from Phoenix last week, she saw something that grossed her out, and validated her stringent travel hygiene habits: A woman changing a baby's diaper on an airplane, with nothing between his naked little bottom and the seat.
"I'm a mother, too, and I would never, ever do that," said Bessiere, director of business development at an event-planning firm in San Francisco.
This sort of incident is what spurs Bessiere, who travels about two weeks a month for work, to wipe down seats with disinfectant, use hand sanitizer religiously and wash her hands regularly. Health experts say her habits aren't in vain especially if the bacteria from a baby's diaper ended up on the glove of a Transportation Security Administration officer during a security check.
Airports and airplanes were never clean places to begin with after all, they're where large crowds from across the world converge in confined spaces.
But as screening procedures get stricter and more passengers opt for pat-downs instead of graphic X-rays, the likelihood of bacteria being spread increases, said Patrick Schlievert, a microbiology and immunology professor at the University of Minnesota Medical School.
The more aggressive the searches, and the more intimate contact there is, the higher the likelihood of transmitting infection, Schlievert said.
"When you touch people, you start picking up their organisms," he told MyHealthNewsDaily. "That might be OK if you wear gloves, but what about everyone else you're touching down the road?"
And when people stand huddled in long lines at security checkpoints and gates, they increase their chance of exposure to bacteria and viruses, he said.
"The key thing you need to do when you get through security is to avoid being coughed on, which can be very hard," Schlievert said. "These organisms are being spread around , and close, crowded places are the best places for doing so."
Although Bessiere is concerned about germs, she thinks the benefits of the security measures outweigh the ick-factor.
"They're taking measures necessary to check people thoroughly," and it's better to go through an uncomfortable search than for a bad guy to get through security scot-free, she said. [Related: Ticked-Off Travelers: Why We Hate the New TSA Screenings]
Where are the germs?
In one hour, adults touch their face 15.5 times, their eyes 2.5 times, their noses five times and their lips eight times on average, said Charles Gerba, a microbiology professor at the University of Arizona.
And the easiest way to catch something is to touch a surface that's been colonized with bacteria, and then touch your face, said Gerba, who is an expert on the prevalence of bacteria on common surfaces.
He recently collected bacteria from 20 airplanes to find the most infected spots. Airplane bathrooms won by a landslide most seeing 50 people between cleanings, and some see 75.
"It's the probably the germiest toilet you'll come across," Gerba told MyHealthNewsDaily.
Most of the bathrooms he swabbed had E. coli bacteria. Thirty percent of sinks, flush handles and faucet handles had E. coli, as did 20 percent of toilet seats, according to his research.
And the closet-sized bathrooms easily allow droplets to splash out of the toilet and land all over the place, he said. Because bacteria thrive in moist environments, the surfaces are ripe for colonization.
And in turn-around flights, there's not much time to clean thoroughly before the next flight's passengers board, Gerba said. Some oft-neglected parts: seat-back trays and the luggage compartment bin handles.
Gerba found norovirus, MRSA and influenza virus on trays. However, he wasn't able to measure levels of the bacteria or viruses to see if they were high enough to make someone very sick.
In airports, check-in kiosks are another area to beware of.
"You've got hundreds of people who use those self-checkout counters," Gerba said. "Every time you push a button, you can transfer a germ."
Dr. Aaron Glatt, president of St. Joseph Hospital in Bethpage, N.Y., said he doesn't think heightened security procedures will increase the likelihood of passing around germs, but he said "there will always be the potential for transmission in a lot of different ways with a lot of different factors."
Contrary to common belief, the air in airplanes is not loaded with germs, Gerba said. Air circulates through air filters, so it's not the same air that's being passed back and forth.
Measures for cleanliness
The TSA provides hand sanitizer to its officers and requires them to wear gloves when doing pat-downs and body searches, said TSA spokesman Greg Soule.
"We promote general good hygiene for officers to protect them and passengers," Soule said.
The bins that hold belongings during the X-ray screens are also cleaned regularly, Soule told MyHealthNewsDaily, though he couldn't give an estimate for how often.
Airlines set their own cleaning and sanitation guidelines for their planes.
American Airlines cleans each plane during its overnight stay in the airport, which includes cleaning the bathrooms, wiping down seats and tray tables, vacuuming the aisles and replacing blankets, said Tim Smith, a spokesman for the airline. And between flights, a cleaning crew checks the lavatories and replaces any obviously soiled blankets or pillows.
Every 30 days, airplanes are given a deep-cleaning. "That's exactly what it sounds like washing seat covers, cleaning carpets and floors, lavatories, bins, tray tables the whole cabin," Smith said.
Flight attendants are also encouraged to sanitize their hands throughout their shift, he said.
Sanitation protocols are similar on Southwest Airlines. Bathrooms are also cleaned throughout the day when the planes stop at one of 26 home bases across the country, Southwest spokeswoman Marilee McInnis said. Planes are scheduled so they hit one of the cleaning stops every few hours.
But clueless passengers can make things dirty despite airlines' best efforts, said Bobby Laurie, a flight attendant who flies up to four times a day.
"You'll find baby diapers inside a seat-back pocket, and the same thing with sunflower seeds," Laurie told MyHealthNewsDaily. "That's mostly what it comes down to, is people don't know how to properly dispose of what they accumulate."
There aren't really any airline procedures beyond requiring attendants to pick up trash every 20 to 30 minutes, he said.
Because crews clean planes overnight, airplanes are cleanest for early-morning flights, and dirtiest during red-eye flights, Laurie said.
"There's not enough time to do it [a deep clean] on the 50 minutes" between flights, he said. "That's why a lot of times when you fly, you'll put down your tray table and find something there. Usually we'll get a call button saying there's something sticky."
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