Disease	Reported annual incidence	Causative agents	Vectors	Geographic distribution
Lyme disease	30,000	Borrelia burgdorferi	Black-legged/deer tick (Ixodes scapularis or Ixodes pacificus)	New England, mid-Atlantic states, upper Midwest, northern California
Rocky Mountain spotted fever and other spotted fever Rickettsioses: Rickettsia parkeri rickettsiosis, Pacific Coast tick fever, Rickettsial pox	6,000	Rickettsia rickettsia R. parkeri Rickettsia species 364D Rickettsia akari	Wood tick (Dermacentor andersoni) American dog tick (Dermacentor variabilis) Brown dog tick (Rhipicephalus sanguineus)	Southeastern and south-central states (Oklahoma, Arkansas, Missouri, Tennessee, and North Carolina account for more than 60% of cases), Arizona and New Mexico
Anaplasmosis	5,000	Anaplasma phagocytophilum	Black-legged/deer tick (I. scapularis or I. pacificus)	Northeast, Midwest, and West Coast
Ehrlichiosis	1,500	Ehrlichia chaffeensis Ehrlichia ewingii Ehrlichia muris eauclairensis	Lone Star tick (Amblyomma americanum) Black-legged/deer tick (I. scapularis) American dog tick (D. variabilis)	Southeastern and south-central states
Babesiosis	1,000–2,000	Babesia microti Babesia duncani	Black-legged/deer tick (I. scapularis or I. pacificus)	Northeast, upper Midwest, few cases in Washington and California
Tularemia	Few hundred	Francisella tularensis	Lone star tick (A. americanum) Wood tick (D. andersoni) Dog tick (D. variabilis)	South-central states (Oklahoma, Arkansas, Missouri, and Kansas)
Colorado tick fever	200–300	Colorado tick fever virus (double-stranded RNA arbovirus)	Wood tick (D. andersoni)	Rocky Mountain region
Tickborne relapsing fever	20–30	Borrelia species: Borrelia hermsii, Borrelia parkerii, Borrelia turicatae	Ticks of Ornithodoros genus	Rocky Mountain region