Characterization of Staphylococcus aureus from Distinct Geographic Locations in China: An Increasing Prevalence of spa-t030 and SCCmec Type III

Abstract

Staphylococcus aureus belongs to one of the most common bacteria causing healthcare and community associated infections in China, but their molecular characterization has not been well studied. From May 2011 to June 2012, a total of 322 non-duplicate S. aureus isolates were consecutively collected from seven tertiary care hospitals in seven cities with distinct geographical locations in China, including 171 methicillin sensitive S. aureus (MSSA) and 151 MRSA isolates. All isolates were characterized by spa typing. The presence of virulence genes was tested by PCR. MRSA were further characterized by SCCmec typing. Seventy four and 16 spa types were identified among 168 MSSA and 150 MRSA, respectively. One spa type t030 accounted for 80.1% of all MRSA isolates, which was higher than previously reported, while spa-t037 accounted for only 4.0% of all MRSA isolates. The first six spa types (t309, t189, t034, t377, t078 and t091) accounted for about one third of all MSSA isolates. 121 of 151 MRSA isolates (80.1%) were identified as SCCmec type III. pvl gene was found in 32 MSSA (18.7%) and 5 MRSA (3.3%) isolates, with ST22-MSSA-t309 as the most commonly identified strain. Compared with non-epidemic MRSA clones, epidemic MRSA clones (corresponding to ST239) exhibited a lower susceptibility to rifampin, ciprofloxacin, gentamicin and trimethoprim-sulfamethoxazole, a higher prevalence of sea gene and a lower prevalence of seb, sec, seg, sei and tst genes. The increasing prevalence of multidrug resistant spa-t030 MRSA represents a major public health problem in China.

Molecular characteristics of antimicrobial resistance and virulence determinants of Staphylococcus aureus isolates derived from clinical infection and food

“…In the present study, 34.18% of all S. aureus isolates (275) were MRSA. The MRSA rate was ~37.84% among clinical isolates, which was consistent with the prevalence of MRSA in China . All 148 clinical isolates demonstrated differing degrees of resistance to antibiotics with the exception of vancomycin, and resistance to penicillin reached 97.97%.…”

Novel spa and Multi-Locus Sequence Types (MLST) of Staphylococcus Aureus Samples Isolated from Clinical Specimens in Korean

“…Some of the health care-associated (HA-MRSA) isolates from Taiwan, the Philippines, and Korea showed the same genotypic characteristics as community-associated MRSA (CA-MRSA) isolates in these countries [6,24,25]. In China, t030 was the predominant spa type [26]. However, it was also reported in Iran as the fifth most common spa type.…”

“…However, it was also reported in Iran as the fifth most common spa type. Moreover, t037 was the second most common spa type in Asia, and was reported in several Asian countries (Korea, China, Taiwan, Iran, and Malaysia) [21][22][23][24][25][26][27][28].…”

High frequency of methicillin-resistant Staphylococcus aureus (MRSA) with SCCmec type III and spa type t030 in Karaj’s teaching hospitals, Iran

“…Methicillin-resistant Staphylococcus aureus (MRSA) continues to be as one of the most important antibiotic-resistant pathogens in many parts of the world over the past decades [1]. The proportion of MRSA among S. aureus isolates is between 52.7% and 93.3% in different regions of Iran and recent data show the increasing rate of these strains [2][3][4][5].…”