Erysipelothrix rhusiopathiae is a non-sporulating, gram-positive, rod-shaped bacterium which was identified as the etiologic agent of swine erysipelas. Infection in man is occupationally related, occurring principally as a result of contact with animals, and mainly found in animal breeders, veterinarians, slaughterhouse workers, and other occupations. Non-occupational cases are very rare. Three forms of human disease have been recognized, including a mild cutaneous infection known as erysipeloid, a diffuse cutaneous form, and a serious although rare systemic complication with septicemia and endocarditis.