This is an 18-month multicenter study to determine if rates of colonization and infection with 2 resistant Gram-positive bacteria - methicillin reseistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococcus (VRE) - among patients in adult intensive care units (ICUs) are lower in ICUs that use an intensive infection control strategy plus standard care compared to ICUs that use standard care alone. The intensive control strategy involves: (1) identifying patients who are colonized with MRSA or VRE by the use of prospective surveillance cultures of the anterior nares (for MRSA) and stool or perianal area (for VRE); (2) Universal Gloving until the patients are discharged or their surveillance culture results shoe they are not colonized with MRSA or VRE; and (3) Contact Precautions during care of patients who arre colonized with MRSA or VRE. Nineteen ICU sites distributed throughout the US are enrolled in the study. Surveillance cultures for the intensive control populations are collected on all patients at the time of admission to the ICU, weekly during their ICU stay, and at the time of discharged. All specimens (approximately 100,000) will be processed in the Clinical Center Microbiology Labs. Specimens will be screened for MRSA or VRE using an enrichment broth technique and selective agar culture methods, and the resistance genes will be detected by PCR. After preliminary work was performed developing the enrichment and selective culture methods, the study was initiated. The first 6 month phase of the study is nearing completion. The incidence of VRE and MRSA colonization varies for each ICU and from month to month. However, an average of 15% of the nasal swabs and 25% of the rectal swabs were positive for MRSA and VRE, respectively. All isolates of MRSA and VRE have been stored at -80 C for future studies, such as characterization of the resistance genes, assessment of resistance to other antibiotics (e.g., vancomycin resistance in MRSA), and epidemiologic analysis for strain to strain differences. Additional studies have been initiated to compare culture techniques with direct detection of resistant bacteria by nucleic acid amplification techniques.
