Model Naomi Campbell recently revealed that every time she gets on a plane, she cleanses all the surfaces around her seat using antibacterial wipes and disposable gloves to avoid catching germs.
She even wears a mask. But is she being paranoid?
Possibly not: a study in 2002 of 1 100 people by the University of California found 20 percent had a cold within a week of flying.
Professor Sally Bloomfield, the chair of the International Scientific Forum On Home Hygiene said: "It’s not surprising, as you have hundreds of people all in one place, potentially spreading germs.”
The most common germs found on planes include those that cause colds, flu and stomach upsets such as norovirus.
It’s not just the proximity that’s to blame: the low-humidity atmosphere (viruses prefer a dry environment) and potential immune suppression that comes from the stress and lack of sleep involved with flying might also make germs more likely to take hold.
Here are some proven ways to reduce your risk:
1. Nab the window seat
"If you sit in the window seat, you are exposed to fewer people during the journey than those in the aisle or middle seats," said Vicki Hertzberg, an associate professor of biostatistics at Emory University in the US. According to a study she led last year, those sitting by the aisle were exposed to 64 different people during their flight, compared with 12 for those by the window.
2. Clean everything
Before you sit down, Professor Bloomfield recommends that, like Naomi, you "use an antibacterial wipe and clean anything you think you might touch to stop you catching any germs". Don’t forget the tray table: a 2015 study for the website TravelMath found this had eight times more bacteria per square inch than the lavatory flush button.
3. Get some air
Travelling with someone who has a cold? Switch on the overhead air vent. "The air forces germ particles towards the floor, reducing the amount to which you’re exposed," said Professor Hertzberg. Hertzberg said the vent won’t spread germs around the plane as the air passes through filters, which removes the most harmful matter.
4. Use hand gel
"Sanitise hands before you eat and after using the toilet: even if you washed your hands, you still touched the door handle," said Professor Bloomfield.
5. Eye drops and nasal spray are essential items
Touching your eyes, nose or mouth is one of the most common ways for germs to enter your body. Eye drops can stop you rubbing dry eyes, and Professor Bloomfield recommends Vicks First Defence Nasal Spray once or twice during a long flight to immobilise viruses that get in the nose.
6. Stay hydrated
"Air on a plane is drier than that on land, which can cause the nose’s mucus membrane to dry out, making it more vulnerable to viruses or bacteria," added Professor Bloomfield.
7. Ditch the mask
Dr Hertzberg said unless it’s tightly fitted, a face mask won’t stop germs getting in, but it helped to prevent germs on the plane if you’re already ill.