Deer Ticks
ASSOCIATED DISEASES
Ticks carry some 20 pathogens in the U.S., including Rocky Mountain Spotted Fever and Heartland virus. But Lyme disease, carried by deer ticks, is the most pressing danger, with about 300,000 cases annually.
CLIMATE-CHANGE IMPACT
They thrive on heat and have spread north at an astonishing rate. Reported cases of Lyme in the U.S. increased threefold since the Nineties.