AN UNUSUAL SOURCE FOR AN OUTBREAK OF METHICILLIN-RESISTANT STAPHYLOCOCCUS-AUREUS ON AN INTENSIVE THERAPY UNIT

During a four-month period, six patients on an intensive therapy unit became colonized or infected with methicillin-resistant Staphylococcus aureus (MRSA). Four of these patients were colonized by the Epidemic MRSA strain 15 (EMRSA 15). The outbreak was characterized by the fact that all four of these patients were nursed in the same bed on the uni t before acquisition of the organism. Investigation of the outbreak le d the authors to believe that the source of the MRSA may have been the exhaust ducting of the adjacent isolation room ventilation system whi ch allowed the organisms to enter the unit via a partially open window positioned above that particular bed. The cycle was broken once the v entilation system was repaired and the window above the bed was proper ly sealed.