Things that should not be touched if possible
But you still inevitably touch them: the armrests of airplane seats. In a scientific study, it was found that the intestinal bacteria E.coli survive there twice as long (96 hours to be exact) than on a smooth surface like the folding tables. Yikes!
But even the folding tables are anything but clean and pure. The aggressive MRSA and noroviruses have already been found there more than once. The reason for this is that it is not uncommon for these tables to be cleaned only once a day. Just like the pockets of the front seat. Since frequently used handkerchiefs or spit bags find room there, these too are a veritable paradise for germs.
Other rather less surprising sources of bacteria are the toilet flush button and also the handles of the toilet door.
On long-haul flights, many passengers ask for blankets or pillows to help them sleep better. However, it is often reserved for passengers on the first flight of the day to snuggle up in fresh bedding. All subsequent passengers have to make do with used blankets - including the bacteria from the previous flight.