The next disease outbreak may start with New York's unbelievably diseased rats

Here's a shocking fact for you: Rats, the cute, cuddly creatures you sometimes see around your city, are actually kind of gross. And to find out just how gross, researchers at New York's Columbia University decided to do some tests, and the answer is clear: They're dangerously gross. The researchers examined the pathogens present in 133 rats in Manhattan and found food-borne illnesses, diseases never-before seen in New York and undiscovered viruses. Peter Daszak, the president of EcoHealth Alliance, told the it's a "recipe for a public health nightmare."

The background: Scientists set traps in a few Manhattan buildings to catch the pests. "New York rats are a lot wilier than rats in other cities," researcher Cadhla Firth told the . "We had to bait traps and just leave them open for a week." Once they had their quota, they were able to extract tissue and look for pathogens. Some of the highlights include salmonella, vicious strains of E. coli and Seoul hantavirus, which had never before been found in New York. They even discovered 18 new viruses, including some that seem similar to the virus that causes hepatitis C.

While that may seem scary, scientists are calling it a good thing - now they can figure out how humans might be affected. The takeaway: The big health scares often deal with pathogens in other parts of the world coming here - Ebola comes to mind, along with our old friends SARS and bird flu. That's why politicians get worked into a tizzy tying disease outbreaks to immigration. But one quick look at some rats and it becomes clear that the U.S. is far from some hygienic paradise that can only be spoiled by foreigners. "Everybody's looking [for pathogens] all over the world, in all sorts of exotic places, including us," Columbia professor Ian Lipkin told the . "But nobody's looking right under our noses."

When the next big illness comes, it has as good a chance of as any of coming from the rats in your city. So give a little thanks that some researchers have started the dirty work. And maybe ask your roommate to stop leaving food out.