An outbreak of group A streptococcal bacteremia in an intensive care unit.

Admission of a patient with group A streptococcal cellulitis and bacteremia to the intensive care unit of a tertiary care teaching hospital was followed by two subsequent cases of group A streptococcal bacteremia with pneumonia in the unit. All streptococcal isolates were the same M- and T-type. Endotracheal intubation with respiratory ventilation was a risk factor for disease acquisition. The characteristics of onset of the two nosocomially acquired cases suggested that a staff member may have been, at least transiently, a streptococcal carrier, but no such carrier was identified. No further cases occurred subsequent to a period when all patients in the unit received antibiotics effective for group A streptococcal therapy.