It’s true we don’t always get to choose who we sit next to on an airplane. But if you find yourself sitting next to someone who is sick, you might want to request a seat change or you may catch more than a sunburn on your next vacation. A recent article in Popular Science shared a story about a team of researchers at the FAA Center of Excellence at Purdue University, who created a simulation of a sneezing passenger to study the mechanics and aerodynamics of germs traveling in airplane cabins.

Artificially ventilated air in close quarters spreads germs throughout the airplane cabin. As you might expect, the people sitting to the immediate left and right of the sneezing passenger face the highest risk of infection. However, the germs spread far beyond the closest seatmates –spreading rapidly throughout the airplane. This is especially significant during flu season, where the risk of contagion from various strains of flu is particularly high, especially in closed indoor environments.

Flu viruses are spread mainly by droplets made when people with flu cough, sneeze or talk. People with flu can spread it to others up to about 6 feet away. These droplets can land in the mouths or noses of people who are nearby and even inhaled into the lungs. A person might also contract the flu by touching a surface or object that has flu virus on it and then touching their own mouth or nose.

According to the Centers for Disease Control and Prevention, healthy adults may be able to infect other people beginning 1 day before symptoms develop and up to 5 to 7 days after getting sick and children can transmit the flu virus for longer than 7 days. So bring along handy wipes and wash your hands frequently throughout the flight.

The findings by the Purdue University researchers highlight the increasing importance of indoor air quality on public health and transportation safety.

As we learn more about germs spreading in pressurized cabin environments like an airplane, we may one day soon see the latest advances in indoor air purification find their way onto the runway, keeping colds and flu off the in-flight menu.