Open AccessMolecular and Clinical Characteristics of Clonal Complex 59 Methicillin-Resistant Staphylococcus aureus Infections in Mainland China
Author(s) -
Juan Li,
Limin Wang,
Margaret Ip,
Mingjiao Sun,
Jing Sun,
Guoying Huang,
Chuanqing Wang,
Li Deng,
Yuejie Zheng,
Zhou Fu,
Changcong Li,
Yunxiao Shang,
Chuanqi Zhao,
Sangjie Yu,
Kaihu Yao,
Yonghong Yang,
Xuzhuang Shen
Publication year - 2013
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0070602
Subject(s) - sccmec , multilocus sequence typing , pulsed field gel electrophoresis , staphylococcus aureus , methicillin resistant staphylococcus aureus , biology , microbiology and biotechnology , virulence , plasmid , typing , staphylococcal infections , genetics , genotype , gene , bacteria
Detailed molecular analyses of Clonal Complex 59 (CC59) methicillin-resistant Staphylococcus aureus (MRSA) isolates from children in seven major cities across Mainland China were examined. A total of 110 CC59 isolates from invasive and non-invasive diseases were analyzed by multilocus sequence typing (MLST), Staphylococcus cassette chromosome mec (SCC mec ) typing, staphylococcal protein A ( spa ) typing and pulsed-field gel electrophoresis (PFGE). Antibiotics susceptibilities, carriage of plasmids and 42 virulence genes and the expression of virulence factors were examined. ST59 (101/110, 91.8%) was the predominant sequence type (ST), while single locus variants (SLVs) belonging to ST338 (8/110, 7.3%) and ST375 (1/110, 0.9%) were obtained. Three SCC mec types were found, namely type III (2.7%), type IV (74.5%) and type V (22.7%). Seven spa types including t437, which accounted for 87.3%, were determined. Thirteen PFGE types were obtained. PFGE types A and B were the major types totally accounting for 81.8%. The dominant clone was ST59-t437-IVa (65.5%), followed by ST59-t437-V (14.5%). The positive rate of luks-PV and lukF-PV PVL encoding (pvl ) gene was 55.5%. Plasmids were detected in 83.6% (92/110) of the strains. The plasmid size ranging from 23.4 kb to 50 kb was most prevalent which accounted for 83.7% (77/92). A significantly lower expression of hla was found in ST59-t437-IVa compared with ST59-t437-V. Among the 110 cases, 61.8% of the patients were less than 1 year old. A total of 90 cases (81.8%) were community-associated (CA) infections whereas 20 cases (18.2%) were hospital-associated (HA) infections. Out of the 110 patients, 36.4% (40/110) were diagnosed with invasive infectious diseases in which ST59-t437-IVa accounted for 67.5% (27/40). In brief, ST59-t437-IVa was proved as the dominant clone in CC59 MRSA strains. The carriage rate of pvl gene was high. CC59 MRSA could result in CA and HA infections. The majortiy of MRSA infection children were in young age.