Molecular Phylogenetic Evidence for Noninvasive Zoonotic Transmission of Staphylococcus intermedius from a Canine Pet to a Human

rRNA-based molecular phylogenetic techniques were used to identify the bacterial species present in the ear fluid from a female patient with otitis externa. We report the identification of Staphylococcus intermedius from the patient and a possible route of transmission. Analysis of 16S ribosomal DNA restriction fragment length polymorphisms indicated that the dominant species present was S. intermedius. A pet dog owned by the patient also was tested and found to harbor S. intermedius. In humans, the disease is rare and considered a zoonosis. Previously, S. intermedius has been associated with dog bite wounds, catheter-related injuries, and surgery. This study represents the first reported case of a noninvasive infection with S. intermedius.