Any handle or surface in public areas, assume the person that handled it before you had just finished taking a monster shit and skipped the handwashing before rubbing their pathogen-factories all over it. Photo in OP, there's not really a good option, so you're in damage control mode... check for toilet seat liners that some public restrooms stock and grab one of them? At least that's something the other people handle before getting shit all over their hands.
One of the nastiest assignments I've had working in a hospital was 'Handwashing Monitor'. And let me tell you, I've debrided infected wounds; wiped maggots out of some fucker's pannus; cleaned up every bodily fluid our bodies are capable of cranking out from the floor, walls, and sometimes ceiling; helped amputate limbs that were literally rotten to the bone, and wiped a cumulative mile or two of ass crack...
...apply to nursing school today!!...
...but anyway, Handwashing Monitor. It is beyond appalling the number of patients, visitors, techs, nurses, doctors, housekeepers, you name it... who'd go in and out of patient rooms without performing hand hygiene; or they'd wash their hands, but for like half a second; or not use soap; or turn the faucet on with their grimy-ass hands, do a thorough handwash, then immediately contaminate themselves by grabbing that same dirty-ass faucet with their bare hands to turn it off. The thing that made that position take the crown above all the other examples I gave in the previous paragraph was the realization that the community who is THE single most painfully aware of pathogens and their origins / mechanism of spreading... can't even wash their fucking hands!
...which brings us back to my opening sentence: it's not advice on sheer ick factor, but a reasonable assumption based on directly observed evidence.
And no, this wasn't just a particularly icky hospital: I've worked in multiple states for multiple organizations/facilities, and to this day get eye-rolls for asking people to re-wash or even first-wash their hands.
We nasty. Be a germaphobe. End rant.

