Tick-borne diseases are common in dogs. Lyme disease, or borreliosis, is caused by "Borrelia burgdorferi" and spread by "Ixodes pacificus" on the West coast of the United States and by "I. scapularis" (deer tick) in the rest of the U.S. Signs and symptoms include fever, joint swelling and pain, lameness, and swelling of the lymph nodes. It has been diagnosed in dogs in all 48 states of the continental U.S. "Ehrlichia canis", which causes canine ehrlichiosis, and "Rickettsia rickettsii", which causes Rocky Mountain spotted fever, are both spread by the American dog tick, "Dermacentor variabilis", and the brown dog tick, "Rhipicephalus sanguineous".