security check
The leading contender for “most infectious airport surface”: the plastic trays used at airport security checkpoints.

When I fly, one of the first things I do after settling into my seat is to pull out a disinfectant wipe from my purse and clean the surfaces around me, including the seat belt buckle, the tray table and the in-flight entertainment screen on the seatback in front of me.

Then I pull out another wipe and clean my hands with it.

I always feel a bit conspicuous doing this housecleaning ritual, but I know such fussiness helps lower my risk of picking up a viral or bacterial infection that could ruin my trip in the days ahead.

A new study, published last week in the journal BMC Infectious Diseases, makes me think I might also want to pull out the disinfectant wipes at an earlier stage in my travels — before I even board the plane. The study found that surfaces throughout the airport — ones passengers frequently come into contact with — harbor respiratory viruses, including strains of influenza.

The leading contender for “most infectious airport surface”: the plastic trays used at airport security checkpoints.

“Plastic security screening trays appear commonly contaminated,” the authors of the study write. That finding makes sense, they add, given that “security procedures [are] an obligatory step for all departing passengers, and that each security tray is rapidly recycled and potentially touched by several hundred passengers per day.”

Also, security trays are non-porous, a factor that prolongs the ability of viruses to survive on their surfaces.

Study details

As background information in the study points out, air travel has made it much easier for infectious diseases to spread between countries and continents. Air travel played a role, for example, in the rapid spread of two of the most serious global viral outbreaks of recent years, the 2003 SARS epidemic and the 2009 H1N1 flu pandemic.

Air travel has also been central in smaller outbreaks, such as a cluster of 33 measles cases that affected people in the United Kingdom and the Netherlands in 2014.

The authors of the current study — a team of researchers from the National Institute for Health and Welfare in Helsinki and the University of Nottingham in the U.K. — decided to take a look at which frequently touched airport surfaces harbored the highest number of respiratory viruses. They collected 90 surface samples and four air samples from various sites within the Helsinki-Vantaa airport during a three-week period at the height of Finland’s 2015-2016 flu season. The samples were then tested for 10 different respiratory viruses.

Nine of the 90 surface samples — 10 percent — and one of the four air samples were positive for viruses. The potentially infectious surface samples included two of three swabs taken from a plastic toy dog in the children’s playground and four of eight taken from plastic trays at the security check area.

Other surfaces that had positive samples were the buttons of a payment kiosk at an airport pharmacy, the divider glass at a passport control point and a set of stair handrails.

The most common virus found in the current study was rhinovirus, which causes the common cold. But the samples also included the influenza A virus, as well as coronavirus and adenovirus, which are also associated with the common cold as well as other mild to severe respiratory ailments.

Interestingly, none of the samples taken in an airport bathroom — on the upper surface of the toilet bowl lid, on the button for flushing, and on the bathroom’s door lock — tested positive for a virus.

The researchers say the bathroom findings are not all that unexpected, “as passengers may pay particular attention to limiting touch and to hand hygiene in a washroom environment.”

Also, the researchers did not test for enteric viruses, which primarily affect the gastrointestinal tract (causing vomiting and diarrhea, among other symptoms) and are transmitted through contact with fecal matter of an infected person.

Reducing the risk

“The presence of microbes in the environment of an airport has not been investigated previously,” said Finnish virologist Niina Ikonen, the study’s lead author, in a press release. “The new findings support preparedness planning for controlling the spread of serious infectious diseases in airports. The results also provide new ideas for technical improvements in airport design and refurbishment.”

In the study, Ikonen and her colleagues recommend that airports enhance the frequency of their cleaning of infectious “hot spots” in airports, such as the plastic trays at security checkpoints. They also urge airports to minimize the spread of viruses through the air by reducing “dense queues” at service counters and elsewhere.

That seems unlikely, at least any time soon.

But travelers can help. “This study supports the case for improved public awareness of how viral infections spread,” said Jonathan Van Tam, one of the study’s authors and a professor of health protection at the University of Nottingham, in the press release. “People can help to minimize contagion by hygienic hand washing and coughing into a handkerchief, tissue or sleeve at all times but especially in public places.”

“These simple precautions can help prevent pandemics and are most important in crowded areas like airports that have a high volume of people travelling to and from many different parts of the world,” he added.

You may also want to bring along your own disinfectant wipes.

FMI: You can read the study in full at the website for BMC Infectious Diseases. For information about what you can do to reduce your risk of becoming infected with a cold or the flu while traveling this upcoming cold-and-flu season, go to the Centers for Disease Control and Prevention’s traveler’s website.

Leave a comment