Any outdoorsperson worth her Smartwool knows she should check herself (and her dogs) for ticks after a jaunt through the backcountry. But let’s be honest—most of us might give Fluffy a once-over, but we usually don’t examine ourselves. Here’s the thing: The Centers for Disease Control and Prevention reported last spring that between 2004 and 2016, tick-borne illnesses in humans more than doubled in the United States, and scientists have discovered seven new pathogens transmitted by the tiny bloodsucking hitchhikers.

Although Colorado’s tick-borne disease rates are low, factors like climate change, booming deer populations, and an influx of people living near and playing in the woods means more folks are being exposed to the little buggers. Here, four truths about ticks all Coloradans should know.

1. Ticks transmit four diseases here: Rocky Mountain spotted fever, tularemia, Colorado tick fever, and tick-borne relapsing fever—plus a condition called tick paralysis. Symptoms of these illnesses range from mild (fever, headache) to severe (permanent paralysis, death). If you get sick after noticing a tick bite, see your doc ASAP. Early treatment is key.

2. New diseases may be on the way in the future, courtesy of the Lone Star tick. One or two of the species have traveled here on animals in recent years. “We’re concerned about it because it carries different diseases than we have here,” says state public health veterinarian Dr. Jennifer House. Bizarrely, a bite from this tick can also cause a meat allergy through the transmission of an enzyme.

3. The deadliest tick-borne disease has Colorado roots. Powassan virus—which is fatal in 10 percent of cases and leaves half of its victims with brain damage—hasn’t been detected in a Coloradan. But scientists first isolated it from a tick found along the Cache la Poudre River in 1952, six years before the first known human case (in Ontario), says Powassan expert Dr. Gregory Ebel of Colorado State University.

4. The best defense is a good offense. If you detach a tick within about three hours of its latch, it can’t transmit most diseases. Forget the burning match and Vaseline. Instead, use tweezers to grasp it firmly behind its head and lift straight up until its mouthparts release. Bag it and freeze it for identification in case of sickness.