That isn't really a hard problem to solve - I simply take a small paper towel and grab the door handle with it. There's usually a bin near the door to throw the

That isn't really a hard problem to solve - I simply take a small paper towel and grab the door handle with it. There's usually a bin near the door to throw the paper towel away. I also remember hearing about some research in a TEDx talk where the presenter said that contrary to expectation, the inside handle of bathroom doors is generally cleaner than your kitchen sink.