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Updated: Jun 14, 2026

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Nationwide surveillance study of vancomycin intermediate Staphylococcus aureus strains in Korean hospitals from 2001

Gyungtae Chung1, Jeongok Cha, Sunyoung Han

  • 1Division of Antimicrobial Resistance, Center for Infectious Disease, National Institute of Health, Seoul 122-701, Korea.

Journal of Microbiology and Biotechnology
|April 8, 2010
PubMed

Insights

We found vancomycin-intermediate Staphylococcus aureus (VISA) in 33 strains among 41,639 methicillin-resistant Staphylococcus aureus (MRSA) isolates in Korea. These VISA strains remained susceptible to newer antibiotics like linezolid.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant global health threat.
  • The emergence of vancomycin resistance in MRSA, including vancomycin-intermediate Staphylococcus aureus (VISA), complicates treatment options.
  • Nationwide surveillance is crucial for monitoring antimicrobial resistance patterns.

Purpose of the Study:

  • To determine the prevalence of VISA among MRSA isolates in Korean hospitals.
  • To characterize the molecular features of identified VISA strains.
  • To assess the susceptibility of VISA isolates to alternative antibiotics.

Main Methods:

  • A nationwide surveillance program screened MRSA isolates from clinical samples between 2001 and 2006.
  • Isolates were screened using brain heart infusion agar with 4 µg/ml vancomycin.
  • Vancomycin Minimum Inhibitory Concentration (MIC) and population analysis profile (PAP) methods were used for confirmation and hetero-VISA (hVISA) classification.

Main Results:

  • Out of 41,639 MRSA isolates, 169 showed growth on selective media, and 33 were confirmed as VISA (MIC = 4 µg/ml).
  • Eighteen of the 33 VISA isolates were further classified as hVISA using the PAP method.
  • All confirmed VISA isolates were susceptible to linezolid, tigecycline, and quinupristin-dalfopristin.

Conclusions:

  • VISA represents a low but present threat within the MRSA population in Korean clinical settings.
  • Molecular characterization revealed specific PFGE patterns and enterotoxin gene profiles in VISA isolates.
  • The susceptibility of VISA to newer agents suggests potential alternative therapeutic options.

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