Those plastic trays at the security checkpoints inside airports harbor viruses that cause respiratory infections, a new study reveals.

British and Finnish researchers did a swab test on most frequently used and touched surfaces around at the Helsinki-Vantaa airport in 2016 to quantify the number of viruses in the high-traffic site.

They took surface and air samples from the playground, pharmacy, handrails, and passport control points. They found that the bathroom is not the dirtiest place in the airport.

Influenza Virus Detected From Plastic Tray Swab

The study published in the journal BioMed Central Infectious Diseases on Aug. 29 revealed that at least one respiratory virus, including influenza A and B, was found in 9 out of 90 surfaces inside the airport. The unlikely suspects that are hotspots for illnesses include plastic toys in the children's playground, the buttons of the payment terminal at the in-house pharmacy, and the passenger side desk at the passport control point.

Most alarmingly, the hand-carried luggage trays at the security check area, which everyone uses, are the most likely to carry harmful viruses.

The researchers revealed that influenza A and B viruses, respiratory syncytial virus, adenovirus, rhinovirus, and coronaviruses were found from the swabs. Rhinovirus, which causes the common cold, is most common in airport surfaces.

In comparison, the samples that were taken from three areas, such as flush, lid, and door lock of the airport public toilet, showed no presence of respiratory viruses.

How To Stop Spreading, Contracting Diseases At The Airport

The study posits that plastic trays pose the highest potential risk inside the airport especially because almost everyone uses them. Because of the high amount of traffic of humans coming in and out of different countries, it is especially easy to spread diseases.

"The presence of microbes in the environment of an airport has not been investigated previously," shared Niina Ikonen of the Finnish National Institute, a virology expert who was involved in the study.

"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."

The researchers hope that their findings would encourage airports to regularly clean these plastic trays and adopt precautions to prevent pandemics. One simple solution to avoid the spread of the virus inside airports is to offer rubbing alcohol or hand sanitizer before and after security checks.

People are also advised to regularly wash their hands and cover their mouths and noses when coughing or sneezing.