Excellent advise..door knobs and handles ...You can buy clean wipes at the drug store and carry them in a bag.
One of the "nursing tricks" I use is after you wash your hands in a public washroom use the towel to turn off the water knob and then use it to open the door to get out.
If you do not you just put all the germs you washed off your hands back on..90% of people do not wash their hand after using the toilet..all those germs are on door push plates and knobs when you leave the restroom..