These are the germiest places on a plane. Here's how to protect yourself while traveling.

Traveling by plane? You might be wondering how clean your seat is — or what germs might be lurking on your flight.

“I think of airplanes as emergency rooms in the air,” Jason Tetro, microbiologist and author of The Germ Code, tells Yahoo Life. “You are surrounded by people you don’t know and their health status is completely unknown. And if there hasn’t been a good cleaning and disinfection, you have no idea about the people who were on the plane before you.”

While airlines conduct cleanings between flights, these practices are not federally regulated or enforced by the Federal Aviation Administration. However, the Centers for Disease Control and Prevention does have guidance on how to prevent the spread of disease on aircraft, which includes how to clean contaminated areas if a passenger is sick with a contagious disease. So where do most germs hide on planes? And how can you protect your health? Here’s what experts say.

What are the germiest places on planes?

Tetro says there have been many attempts to identify the germiest places on planes, and most point to areas that have the greatest exposure to bodily fluids and hands. “These include the seat pocket, the seat belt, the tray table and the restroom handle. But the germiest place of all is the headrest because it is the most exposed and the most touched surface on a plane,” says Tetro.

For a Washington Post story, travel reporter Andrea Sachs conducted her own non-scientific test using a swab kit she obtained from an AAA inspector who tests the cleanliness of hotels. Sachs used the swab on seven high-touch points in the main cabin of the plane and three areas in the plane’s bathrooms. She first tested each place as it was and then again after she cleaned the areas with a Clorox wipe. Based on her test, she found the following to be the top five germiest areas:

· Bathroom sink handle

· Tray table

· Inside bathroom door handle

· Seat belt buckle

· Armrest

However, here’s some good news: Dr. William Schaffner, professor of infectious diseases at Vanderbilt University Medical Center, says that while you could conceivably pick up a virus from these surfaces, the risk is much lower than people think. He explains that viruses need human cells to multiply.

“They can’t multiply on those surfaces,” he tells Yahoo Life. “Some viruses can survive longer, and it depends on the temperature, the humidity and the type of surface, so different viruses will survive for different periods of time on those surfaces, but over time, they die off because they can’t multiply.”

People make people sick on planes

Rather than surfaces on a plane, Schaffner says the risk of becoming sick from respiratory viruses like common colds, influenza, COVID-19 and respiratory syncytial virus (RSV) comes from being within three to six feet of infected people in enclosed spaces for a long period of time.

“They breathe it out and then you breathe in that air with the virus and that’s how you get infected,” he says. “This can happen during the entire period of travel, when you’re in the airport, the cab, the bus, railroad cars, etc. Also being in the terminals, in the restaurants, in the restrooms.”

However, he notes that just because one person on a plane has a virus doesn’t mean everyone on the plane will be exposed via aerosols from coughing and sneezing. He compares air on a plane to slices of bread in a loaf; so if you’re in coach, for example, you’re not exposed to what’s happening in first class.

“It’s been well demonstrated that the air handling on airplanes is very segmental, and when there has been transmission of a virus or other infection on an aircraft, it’s usually on longer flights and the people at risk are the folks in your same row and two rows in front of you and two rows in back of you,” Schaffner explains.

When it comes to bodily secretions from a passenger, though, the risk may increase. For instance, in September, Delta Air Lines turned back a plane bound for Barcelona, Spain, when a passenger suffered a severe case of diarrhea. Audio posted on LiveATC.net that was then posted on X, formerly known as Twitter, shared what seems to be the pilot saying, “This is a biohazard issue. We’ve had a passenger who had diarrhea all the way through the airplane, so they want us to come back to Atlanta.”

When there is a case like this involving diarrhea, Tetro says the plane could be contaminated with a few potential pathogens. “All of them are highly contagious and in some cases airborne,” he says. “If the diarrhea cannot be contained to the restroom, there is a very good chance others will be infected. It’s no different than a cruise ship in that sense. Once the pathogens are in the environment, people will be exposed and many will end up sick.” Other recent reports of biohazards on planes include passengers being exposed to blood and vomit.

How to protect yourself from germs on planes

Hand hygiene is your best defense against germs on planes, says Schaffner. “The hands are the intermediary, so you touch the table and then you touch your eyes or mouth — and people do that all the time, more frequently than you would anticipate. And by doing this you could pick up a few viruses on your fingertips.”

To interrupt transmission of viruses to your nose or mouth, he suggests frequently washing your hands with soap and water when possible or using hand sanitizer rather than focusing on cleaning surfaces around you. “People have the tendency to want to wipe them down…but rather than walking around trying to use a disinfectant wipe on all the surfaces you’re going to find in the world, take care of your hands,” says Schaffner.

Wearing a mask while traveling also helps. Tetro says that after he was infected from a sick passenger on a plane before the pandemic, he started wearing barrier protection when flying. “In the pre-COVID era, it was in the form of a scarf or neck tube/gaiter. Now I use a mask to prevent those droplets and aerosols from getting into my nose and mouth,” he says.

Ensuring that you’re up to date on immunizations is another form of protection, says Schaffner. “If I were traveling during [cold and flu season], I would not want to travel if I were not vaccinated against flu, COVID — with the updated vaccine — and if I were older, I would for sure get the RSV vaccine also,” he says.

This article was originally published on Dec. 20, 2023 and has been updated.