Duration of Methicillin-Resistant Staphylococcus aureus Carriage, According to Risk Factors for Acquisition

Abstract

OBJECTIVE. To examine the duration of methicillin-resistant Staphylococcus aureus (MRSA) carriage and its determinants and the influence of eradication regimens. DESIGN. Retrospective cohort study. SETTING. A 1,033-bed tertiary care university hospital in Bern, Switzerland, in which the prevalence of methicillin resistance among S. aureus isolates is less than 5%. . Failure of decolonization treatment was associated with the presence of risk factors at the time of treatment (P = .01). Intermittent screenings that were negative for MRSA were frequent (26% of patients), occurred early after first detection of MRSA (median, 31.5 days), and were associated with a lower probability of clearing colonization (HR, 0.34 [95% CI,) and an increased risk of MRSA infection during follow-up.CONCLUSIONS. Risk factors for MRSA acquisition should be carefully assessed in all MRSA carriers and should be included in infection control policies, such as the timing of decolonization treatment, the definition of MRSA clearance, and the decision of when to suspend isolation measures.

Evolution of Multidrug-ResistantStaphylococcus aureusInfections in Horses and Colonized Personnel in an Equine Clinic Between 2005 and 2010

“…This could be due to possible failures of the decolonization or to the presence of many risk factor such as antibiotic selective pressure and the spread of MRSA between horses and personnel. 26,38 Additionally, repeated decolonization with mupirocin may select for a mupirocin-resistant MRSA-population. 32 Persistent staphylococci carriage and intermittent staphylococci colonization in humans is well described and occurs in about 30% and 60% of the population, respectively.…”

“…The prevalence of MRSA and BORSA carriage in the personnel was calculated by dividing the number of carriers by the number of persons sampled. During the follow-up after the decolonization treatment of the personnel, samples were taken from the nose, throat, and the inguinal region as previously described 26 .…”

“…26 Mupirocin was applied thrice a day in both nares, a 0.1% chlorhexidin solution was gargled twice daily to decolonize the pharynx, and the body and the hair were washed by showering with 4% chlorhexidin soap once a day. This procedure was repeated for 5 days.…”

“…Clearance of MRSA was assumed when two or more swabs were negative during the final follow-up screenings using a selective culture. 26 …”

Low Yield of Methicillin-Resistant Staphylococcus aureus Screening in Hemodialysis Patients: 10 Years’ Experience

“…This finding is in agreement with an earlier study in our hospital aiming to examine the duration of MRSA carriage, its determinants, and the influence of an eradication regimen performed on 116 patients (including but not limited to those on hemodialysis), which revealed the median time to clearance to be 7.4 months. 15 Because no decolonization regimes were administered during the study period, we cannot estimate what marginal benefit in reducing MRSA infection such a strategy might have achieved.…”