Filthy flights: Three germy items you don't want to touch at an airport

While many already know airports are a breeding ground for bacteria, a new study has discovered the location of the most germy hotspots – and the results are enough to make the most carefree traveller squirm.

The study, conducted by at three different US airports, tested the average number of viable bacteria and fungal cells (or colony-forming units) per square inch.

Topping the list of the germiest surfaces were the self check-in kiosks with a whopping 253,857 CFU recorded on average – more than 1400 times dirtier than a toilet seat.

One screen even measured over 1 million CFU, making them the surface most likely to make you sick.

Check-in kiosks were found to be the germiest surface at the airport, with one screen alone recording more than one million CFU. Source: AAP

Armrests of the chairs in the waiting lounge ranked second in the study, with a result of 21,630 CFU per square inch.

In third place was the button of the airport water fountains with 19,181 CFU recorded.

As for the planes, the germiest surface was found in the bathrooms.

Armrests at airport lounges came in second place. Source: Getty

The toilet's flush button was found to carry 95,145 CFU, while the tray table – where passengers eat from – recorded 11,595 CFU.

You might think twice next time you fasten your seatbelt, as the buckle itself came in third place with 1116 CFU per square inch.

Compared to a regular household, the numbers are huge.

Unsurprisingly, the germiest place on the plane was in the bathroom. Source: Getty

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A standard kitchen countertop, typically the germiest place in a home, contains a count of 361 CFU.

While the planes are quickly checked between flights, it's up to the individual airline to determine how frequently the planes are cleaned.

With advances in technology, some airline kiosks now include facial recognition to check-in for flights, so you no longer have to risk illness with the touch screens.