On a dare, a kid in New York City licked an entire handrail at the entrance of the subway for a dollar -- and presumably all the benefits of YouTube stardom. This, it goes without saying, is gross. But we wanted to know exactly how gross it is.

“If anyone dares you to lick anything in public, lick a toilet seat,” says Charles P. Gerba, a microbiologist at the University of Arizona. “It would be safer to lick a toilet than a handrail on a bus.”

Gerba has examined levels of germs in public places such as bus seats, bus handrails, indoor handrails and toilet seats. He found that about 50 different microorganisms live on a toilet seat while a handrail provides refuge for hundreds of thousands of germs.

“Americans are terrified of butt-borne diseases,” he says, explaining why toilet seats are so clean. Most people wipe off toilet seats or use seat covers, but we give little thought to the condition of railings.

“We’ve studied the microbiology on public buses,” Gerba says. “The handrail is fairly bad.”

Gerba found e-coli (a bacterium often responsible for food poisoning); MRSA (methicillin-resistant Staphylococcus aureus, a staph infection that’s resistant to most first-line antibiotics); and fecal matter on handrails. Fecal matter is on 50 percent of all handrails (people, it’s time to seriously wash your hands after using the bathroom). It’s not uncommon for handrails to have flu, staph bacteria, and respiratory and cold viruses, as well. Previous research in England found that people are more likely to get a cold from handrails than any other public surfaces.

After all, as Gerba reminds, "you don’t know if the last guy washed his hands after using the toilet.”

He recommends that public transportation riders apply hand sanitizer after arriving at their destination.

Even though the rail licker exposed himself to as many as 300,000 microbes, he probably won’t get sick.

“I think the likelihood that he will get ill is very low. We all have bacteria in our mouth that are normal that will provide us with protection,” says Mary Jo Kasten, an assistant professor of medicine at the Mayo Clinic. “If [the railing] has fecal matter on it, maybe [he] could get hepatitis A or another infection.”

As disgusting as it looks, licking a railing isn’t the best way to transmit infectious diseases. “Licking an inanimate object is not a way that I think of people getting infected. He’s more likely to transmit a virus if he actually kissed someone,” Kasten says. (The existence of this video exponentially decreased his chances of actually kissing anyone).

Gerba says that no amount of money would entice him to lick a handrail (he’s not interested in licking toilet seats either, despite knowing they’re cleaner). Is there anyway he’d ever lick a handrail? “I’d have to drink a lot,” he jokes.

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