ABSTRACT
Staphylococci are commensal bacteria of the anterior nares, skin, and the gastrointestinal tract of humans that rarely cause systemic infections in otherwise healthy individuals, and therefore are considered opportunistic pathogens. Through various mechanisms, adult humans and animals attain an innate but incomplete natural protection from staphylococcal infections. Partial protection is afforded by mucosal and epidermal barriers, in addition to possible immunological mechanisms that impart resistance. Interruption of these natural barriers as a result of immunosuppressive diseases or therapies, or injuries such as burns, traumas, or surgical procedures involving indwelling medical devices, increases the risk for staphylococcal infections [1,2]. Nasal carriage of Staphylococcus aureus is reportedly one of the major risk factors for surgical wound infections after surgery, and for infections of the vascular access site in hemodialysis patients [3-5]. It is estimated that staphylococcal infections account for >50% of all hospital-acquired infections. S. aureus alone is responsible for 15-25% of such infections and is surpassed only by S. epidermidis, which reportedly accounts for as many as 35% of these infections [6-12]. Staphylococcal infections, especially those caused by S. aureus, are associated with high morbidity and mortality [13,14].
