National surveillance for Lyme disease began in 1982 and since then the number of reported cases have grown over 25-fold.
Between 1990 and 2015, the number of reported cases in the U.S. doubled.
The disease has also spread geographically.
According to the Centers for Disease Control and Prevention (CDC), it’s the fastest growing vector-borne infectious disease in the U.S.
The CDC reports the disease, and the ticks that carry the disease, are concentrated in the northeast and upper Midwest. Ticks carry more than Lyme disease, including Rocky Mountain spotted fever and human babesiosis, a rare microscopic parasite that infects red blood cells.