Lyme disease, a bacterial illness, has been around for decades but became a significant health threat only in the late 1980s. The Centers for Disease Control and Prevention now receive about 20,000 reports of the disease a year.

“Lyme disease is serious, as it can enter the nervous system and cause lifelong damage,” says dermatologist David A. Berman. If you are bitten by a tick, watch for the telltale signs of Lyme disease: a rash that spreads around the bite, usually starting a few days after you were bitten; fever, chills, and muscle aches; extreme fatigue; and neck stiffness that can set in quickly or weeks later.

If you are experiencing some of these symptoms, take a Lyme test, available through your doctor. If you do have Lyme disease, your doctor will most likely prescribe a course of doxycycline, the antibiotic of choice for Lyme.