Comparison of Environmental MRSA Levels on High Touch Surfaces in Contact Isolation and Non-Contact Isolation Patient Rooms: A Veterans Hospital Study
Methods: We identified each contact isolation patient room (occupied by a patient with active MRSA colonization or infection) and non-contact isolation patient room using infection control databases. A total of 5 surfaces were sampled in both the arms (tray table, toilet seat, toilet grab bar, bedrail and call button). The samples were obtained using Rodac contact plates (Hardy Diagnostics, Santa Maria, CA) in a patient room where the patient had at least 2 days of stay. Roll plate technique was used for non-flat surfaces. The contact plates were then incubated at 35-37OC for 48 hours. Deep Pink or mauve colored colonies were identified as MRSA and the total colony counts were recorded. Further, these colonies were confirmed as MRSA by using standard methods. When the colony counts for MRSA were greater than 200 or too numerous to count, they were recorded as 200 to avoid outliers.
Results: We had a total of 23 rooms in the Non-MRSA arm and 39 rooms in the MRSA arm. The total number of colonies identified were 93 (non-MRSA arm) &1593 (MRSA arm). The average colony count per surface was 0.80 and 8.1 respectively for non-MRSA and MRSA arms.
Conclusion: Non-MRSA rooms have MRSA, but the burden is far lower than MRSA rooms. This may further provide insight into the transmission cycle of MRSA in a hospital setting, especially in closed systems like Veterans hospitals. Further, the non-MRSA rooms may have a role in nosocomial transmission in a hospital environment.
Xenex Healthcare Services: Grant Investigator, Research grant
K. Sikes, None
N. Ganachari-Mallappa, None