An abscess is a deep, localized bacterial infection characterized by a walled-off collection of purulent material. It is most frequently caused by Staphylococcus aureus. This is a common condition.

Methicillin-resistant S. aureus (MRSA) first emerged as an important nosocomial pathogen in the 1960s. In more recent years, community-acquired outbreaks of MRSA (CA-MRSA) have been described increasingly among healthy individuals lacking the traditional risk factors for such infections (intravenous [IV] drug use, incarceration, participation in contact sports, etc). These strains have a propensity for causing abscesses, furunculosis, and folliculitis and have a unique antibiotic susceptibility profile from health care associated strains of MRSA.

It has been shown that the majority of purulent skin and soft tissue infections presenting to emergency rooms across the United States are caused by CA-MRSA.