CP and infection: Both patients in this cluster received prolonged mechanical ventilation and had routine serial sputum cultures for surveillance of infection-related ventilator-associated complications.§§ Among the 16 patients hospitalized in room X between the occupancies of patient 1 and patient 2, only five had respiratory specimens cultured during hospitalization, and CP-CRPA was not isolated from any specimen; it is possible that the shorter stays (≤12 days) or lack of mechanical ventilation reduced transmission risk.