The culprit is the common wood tick (D. variabilis), also known as the American dog tick. Its range already sprawls across central and eastern North American, from the Gulf of Mexico to southern Canada. It carries diseases that make both people and animals sick.
These include the human ailments of Lyme disease and Rocky Mountain spotted fever and a parasitic disease that kills domesticated cats.
The study concludes, "Due to the ability of D. variabilis to harbour and transmit pathogens, a change in the distribution of this species could also affect the risk of human and animal diseases throughout North America, particularly in the northern range of the tick (Canada) The research was conducted by a team of four scientists from the University of Guelph, Ontario, Canada.