Objective: To describe the epidemiology and natural history of colonization with vancomycin-resistant Enterococcus faecium (VREF) in a long-term care facility.
Design: All patients in whom VREF was isolated were followed prospectively, with rectal swab cultures at 2-week intervals, until discharge, death, or clearance of VREF. Clearance was defined as two consecutive negative cultures. In addition, three prevalence surveys were conducted of all patients in residence on one 34-bed intermediate care ward.
Setting: A 400-bed, long-term care Veterans Affairs facility.
Participants: Thirty-six patients colonized with VREF.
Results: Vancomycin-resistant Enterococcus faecium was identified in 24 of the 36 patients at the time of transfer from an acute care facility. Seventeen patients had concomitant methicillin-resistant Staphylococcus aureus, and seven patients had a recent history of Clostridium difficile-associated diarrhea. VREF in these patients persisted for a median of 67 days after identification. Treatment of VREF colonization with antimicrobials was associated with prolongation of colonization. Serial surveillance of the 34-bed ward found stable rates of colonization, with only three documented instances of VREF acquisition. During 2.5 years of surveillance for infection, a single case of bacteremia occurred in a patient in whom colonization with VREF could not be demonstrated by rectal swab culture. No infections occurred in patients colonized with VREF.
Conclusions: Long-term care patients have protracted carriage of VREF. Most will improve over time; however, receipt of antimicrobial therapy is associated with prolongation of VREF carriage. The risk of VREF infection is low in this population. When there are appropriate contact precautions, patient to patient transmission occurs at a low rate. These observations can be used to design a practical infection control strategy for long-term care facilities.