The possibility of contracting Ebola in an American city has now dominated headlines, dinner conversations, and Twitter for more than a week. Still, the chances of catching it are minuscule (like one in more than 13 million ). Perhaps city dwellers should worry more about rats.

Earlier this month, the pest control company Orkin released a ranking of the top rattiest cities–the places that sent out the most rodent-elimination requests in the year 2013. Here are the top 10 winners:

Chicago Los Angeles Washington, D.C.-Hagerstown New York San Francisco-Oakland-San Jose Seattle-Tacoma Detroit Cleveland-Akron-Canton Baltimore Miami-Ft. Lauderdale

Rats are well-suited to carry lots of different diseases that are harmful to humans. Hantavirus, the bubonic plague, and Leptospirosis (a disease causing liver damage) are just a few. Some research suggests that rat infestation problems could be worsened by climate change, as rats tend to breed in warmer and wetter weather. If rising sea levels mean increased flooding, that could mean more ideal habitats for rats to raise families.

Rat sightings and rat-related damage to electrical cables have become such issues in New York City that city officials have taken steps to sterilize them. Earlier this year, the city launched a $611,000 pilot program to eliminate burrows, and in 2013, the Metropolitan Transit Authority started studying how to neuter the rodents. The city’s new organic trash pilot program also features rat-proof lids to keep the critters out.

But New York only comes in fourth place on Orkin’s list; Chicago tops the rankings. That’s part of the reason why the Chicago Department of Innovation and Technology (DoIT) last year partnered with Carnegie Mellon University to take a predictive approach to its ongoing “war on rats.”

While we’re waiting for quick fixes, ‘tis the season to stay alert for rodents, Orkin warns. In colder weather, they tend to seek warmer–and more human–environments.