Population structure analyses of Staphylococcus aureus at Tygerberg Hospital, South Africa, reveals a diverse population, a high prevalence of Panton–Valentine leukocidin genes, and unique local methicillin‐resistant S. aureus clones. (9th December 2013)

• Record Type: Journal Article
• Authors: Oosthuysen, W. F.; Orth, H.; Lombard, C. J.; Sinha, B.; Wasserman, E.; Lina, G.
• Is Part Of: Clinical microbiology and infection. Volume 20:Number 7(2014:Jul.)
• Page Start: 652
• Page End: 659
• Publication Date: 2013-12-09
• Subjects: Medical microbiology -- Periodicals; Diagnostic microbiology -- Periodicals; Communicable diseases -- Periodicals; Infection -- Periodicals; 616.01
• DOI: 10.1111/1469-0691.12452
• Languages: English
• ISSNs: 1198-743X

Abstract

<abstract abstract-type="main" id="clm12452-abs-0001"> <title>Abstract</title> <p>Studies reporting on the population structure of <italic>Staphylococcus aureus</italic> in South Africa have focused only on methicillin‐resistant <italic>S. aureus</italic> (MRSA). This study describes the population structure of <italic>S. aureus</italic>, including methicillin‐susceptible <italic>S. aureus</italic> (MSSA) isolated from patients at Tygerberg Academic Hospital, Western Cape province. Pulsed‐field gel electrophoresis (PFGE), detection of Panton–Valentine leukocidin (PVL), <italic>spa</italic> typing, multilocus sequence typing (MLST), <italic>agr</italic> typing and SCC<italic>mec</italic> typing were used to characterize strains. Of 367 non‐repetitive <italic>S. aureus</italic> isolates collected over a period of 1 year, 56 (15.3%) were MRSA. Skin and soft tissue infections were the most frequent source (54.8%), followed by bone and joint (15.3%) and respiratory tract infections (7.7%). For strain typing, PFGE was the most discriminative method, and resulted in 31 pulsotypes (<italic>n</italic> = 345, 94.0%), as compared with 16 <italic>spa</italic> clonal complexes (CCs) (<italic>n</italic> = 344, 93.4%). Four MLST CCs were identified after eBURST of sequence types (STs) of selected isolates. One hundred and sixty isolates (MSSA, <italic> n</italic> = 155, 42.2%) were PVL‐positive, and <italic>agr</italic> types I–IV and SCC<italic>mec</italic> types I–V were identified. Our <italic>S. aureus</italic> population consisted of genotypically diverse strains, with PVL being a common characteristic of MSSA. MSSA and MRSA isolates clustered in different clones. However, the dominant MRSA clone (ST612) also contained an MSSA isolate, and had a unique genotype. Common global epidemic MRSA clones, such as ST239‐MRSA‐III and ST36‐MRSA‐II, were identified. A local clone, ST612‐MRSA‐IV, was found to be the dominant MRSA clone.</p> </abstract>