Germs love the plastic security trays, according to a study from the University of Nottingham and the Finnish National Institute for Health and Welfare.

For the study published in BMC Infectious Diseases, researchers swabbed a variety of frequently touched surfaces at Helsinki-Vantaa airport during peak travel time in the winter of 2016. They discovered viruses on 10 percent of all the tested surfaces, including staircase rails, passport checking counters, and payment terminals.

But the most popular hotspot for infections like rhinovirus (the common cold) and influenza was the plastic security bins where passengers dumped their shoes, phones, and carry-on bags.

Even worse, the study concluded that although the viruses found on frequently touched surfaces may not cause disease, the microbes can survive on “various materials” for “up to several days.”

The study’s researchers hope that the findings “improve public awareness of how viral infections spread.”

In a statement, the University of Nottingham’s Professor of Health Protection Jonathan Van Tram suggested that travelers minimize the spread of contagious viruses by washing their hands and coughing into a handkerchief or sleeve while in public, which is the same advice elementary school teachers give their students.

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

It should be noted, however, that the study was only conducted at one airport. Considering that sanitation practices likely differ between airports, security bins may be contain more germs at some than others.

According to the University of Nottingham the study is part of a larger research project funded by the European Union that investigates how airports and other travel-heavy checkpoints are platforms for spreading serious infections. Organizers hope that the research will “strengthen public health advice in preparation for future flu pandemics.”

Virology expert Niina Ikonen, who co-authored the study, suggested “technical improvements” that could limit the spread of germs. She concludes that airports could provide free hand sanitizer where “intense, repeat touching of surfaces takes place.”

So after you grab your phone and shoes from airport security, consider washing your hands. You don’t know what microscopic creatures are crawling across your screen.