Carriage and Genetic Diversity of Methicillin-Resistant Staphylococcus aureus among Patients and Healthcare Workers in a Serbian University Hospital

• Published in: PloS one Vol. 10; no. 5; p. e0127347
• Main Authors: Cirkovic, Ivana, Stepanovic, Srdjan, Skov, Robert, Trajkovic, Jasmina, Grgurevic, Anita, Larsen, Anders Rhod
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 20-05-2015; Public Library of Science (PLoS)
• Subjects: Adult; Aged; Aged, 80 and over; Analysis; Anti-Infective Agents - pharmacology; Bacterial Typing Techniques; Biodiversity; Carriages; Carrier State - microbiology; Confidence intervals; Cross infection; Emergency medical services; Epidemiology; Female; Genetic aspects; Genetic diversity; Genetic Variation; Health aspects; Health care; Health Personnel; Hospitals; Hospitals, University; Humans; Immunology; Laboratories; Male; Medical personnel; Medicine; Methicillin; Methicillin-Resistant Staphylococcus aureus - classification; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - genetics; Microbial drug resistance; Microbial Sensitivity Tests; Microbiology; Middle Aged; Multidrug resistance; Nasal Cavity - microbiology; Oxacillin; Oxacillin - pharmacology; Patients; Pharynx; Pharynx - microbiology; Prevalence studies (Epidemiology); Screening; Serbia; Staphylococcus aureus; Staphylococcus infections; Studies; Surgery; Surveillance; Typing; Workers; Young Adult; Serbia
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0127347

There is a paucity of data on methicillin-resistant Staphylococcus aureus (MRSA) epidemiology among Balkan countries. The aim of our study was to determine the prevalence of nasal and pharyngeal carriages and diversity of MRSA among patients and healthcare workers (HCWs) in the major referral centre in Serbia, and to evaluate performance of three different media for MRSA screening.
Nasal and pharyngeal swabs were obtained from 195 patients and 105 HCWs in Emergency Department (ED), Surgical Department (SD) and Medical Department (MD). After broth enrichment, samples were inoculated onto MRSA-ID, ORSA and oxacillin-MSA and incubated for 24/48 hours. Characterisation of isolated MRSA strains was determined by MLVA, spa, SCCmec and agr typing, PVL genes detection and antimicrobial susceptibility.
MRSA carriage prevalence was 11.8% in patients and 7.6% in HCWs. Introduction of pharyngeal swabs in screening procedure increased MRSA carriage rate by over 30%. Variable found to be independently associated with an increased risk for MRSA carriage was ED (odd ratio (OR) = 4.45, 95% confidence interval (CI) 1.78-11.14). A higher risk of multidrug-resistant MRSA carriage was observed among patients (OR = 22; 95% CI 1.92-251.54). CC5-MRSA-SCCmecI was the dominant clone among patients and HCWs in ED and MD, while high genetic diversity of community-associated MRSA (CA-MRSA) was shown in SD especially among HCWs. MRSA-ID was superior to the other tested media with a sensitivity/specificity of 95.2% and 99.6% after 48 hours of incubation.
These results indicate high MRSA carriage rate in the hospital and emergence of CA-MRSA through HCWs in these settings. MRSA-ID was the optimal available choice for MRSA screening.