Where on the plane is the risk of illness greatest?

Your nose is running, your throat feels itchy, and as you board the plane, it sounds more like a doctor’s waiting room than an aircraft cabin. All around, passengers are coughing, sneezing, and blowing their noses.

For many travelers, this is sheer horror. Being crowded into a small space, exposed to the same air for hours on end – sounds like a perfect breeding ground for viruses. But is that really true? And where is the risk of illness greatest? A US study shows: Those who sit correctly fly surprisingly safely.

Researchers at Emory University and Georgia Tech meticulously observed the behavior of over 1,500 passengers and 41 crew members on ten US domestic flights. These movement profiles were used to create a network model that simulated the spread of droplet infections.

The most important finding: Infections remain local. Only those who are within one meter of an infected person—that is, in the same row, or one row in front of or behind them—are at significant risk. An infected passenger infects an average of 0.7 other people; an infected crew member, on the other hand, infects four to five, primarily because they move around a lot and come into brief contact with many passengers.

Surprisingly, not a single trace of influenza or other respiratory viruses was found in 220 samples taken from armrests, toilet doors, and seatbelts — even though the flights took place at the height of flu season.

Window seats are the safest

Passengers seated by the window have the fewest interactions — averaging just 12 contacts per flight, mostly with their immediate neighbors. Those who remain seated throughout the journey tend to stay the healthiest. In contrast, passengers in middle seats average 58 contacts, while those in aisle seats have as many as 64, with fellow travelers and crew frequently passing by. The risk of infection, researchers note, rises with the level of movement in the aisle.

According to the simulation, the eleven seats directly surrounding an infected person in an aisle seat are particularly at risk – in their own row, as well as one in front of and one behind them, in aisle and middle seats. The safest place is in the window rows, and preferably at the very front or back of the plane, where there is less traffic.

The researchers' conclusion: Flying is safer than many people think. Thanks to HEPA filters and efficient air circulation, the cabin air is completely replaced every few minutes. Those who also disinfect their hands and avoid constantly touching their faces have a good chance of staying healthy.