Infections by Streptococcus equi subspecies zooepidemicus occur in animals. In human beings these infections are generally accidental, and few cases have been reported. We present the case of a 56-year-old male, a butcher, who presented with abdominal pain. Aneurismatic dilatation of the aorta below the renal arteries was documented by CT-scanning. A purulent collection and arterial ulceration were found during surgery; Streptococcus equi zooepidemicus was isolated from the collection and from blood cultures (Acta Med Colomb 2009; 32: 85-87).