We naturally perceive public toilets to be gross, which is why lots of people use a toilet seat cover to protect their bare butts from touching anything nasty. But experts believe that those seemingly life-saving covers aren't actually that effective at all.
Turns out, since toilet seat covers are absorbent and bacteria and viruses are microscopic, they can easily pass through the paper that makes up the cover. But don't freak out just yet!
While it's likely that your skin is coming in direct contact with germs, public health researcher Kelly Reynolds told USA Today that the risk of actually contracting an infection from a toilet seat is pretty unlikely—that is unless you have an open wound down there, in which case your risks are slightly higher.
Even still, germs have a better chance of spreading after you flush when an invisible cloud of poop is hurled into the air—a phenomenon known as "toilet plume," according to USA Today. This can also be caused by squatting over the toilet and causing, er, splashes to go everywhere. (See also: 5 Bathroom Mistakes You Don't Know You're Making)
Reynolds says that the "bits of fecal matter settle on surfaces" and "contaminate hands and then get spread to the eyes, nose or mouth." (We'll just let that sink in for a second)
So, the best way to actually avoid getting an infection from a public restroom would be to cover your seat with a lid before flushing. But if that's not an option, wash your hands immediately after going to the bathroom—something you should be doing anyway.