Spotted fever group Rickettsia were present in 13 of 1,171 (1.1%) of adult Dermacentor variabilis Say removed from raccoons (Procyon lotor L.) and Virginia opossums (Didelphis virginiana Kerr) in western Tennessee. Spotted fever group Rickettsia were detected by amplification of a 617-bp segment of the citrate synthase gene by polymerase chain reaction.