The present disclosure provides immunogenic compositions and vaccines effective for reducing the incidence of or severity of clinical signs or symptoms of infection by a tick-borne pathogen selected from the group consisting of Rickettsia rickettsii, Ehrlichia chaffeensis, Ehrlichia canis, Ehrlichia ruminantium, Anaplasma marginale, and Anaplasma phagocytophilum. In preferred forms, the immunogenic composition comprises an inactivated whole cell bacteria selected from the group consisting of Rickettsia rickettsii, Ehrlichia chaffeensis, Ehrlichia canis, Ehrlichia ruminantium, Anaplasma marginale, Anaplasma phagocytophilum, and any combination thereof, together with an adjuvant.