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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Increasing prevalence of methicillin-resistant Staphylococcus aureus infection in California jails

Erica S Pan1, Binh A Diep, Heather A Carleton

  • 1Department of Pediatrics, San Francisco General Hospital, San Francisco, California 94110, USA. fpr@epi-center.ucsf.edu

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|October 30, 2003
PubMed

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) prevalence significantly increased in San Francisco jail inmates from 1997 to 2002. Most MRSA strains were SCCmec type IV and genetically linked to an LA County jail outbreak.

Area of Science:

  • Infectious Diseases
  • Microbiology
  • Epidemiology

Background:

  • Staphylococcus aureus is a common cause of infections.
  • Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant public health threat.
  • Jail systems can be environments for the rapid spread of infectious diseases.

Purpose of the Study:

  • To investigate the prevalence and characteristics of MRSA among inmates in the San Francisco County jail system.
  • To determine the genetic relatedness of MRSA isolates to other known strains.

Main Methods:

  • Analysis of clinical isolates from jail inmates between 1997 and 2002.
  • Detection of methicillin resistance.
  • Staphylococcal chromosomal cassette mec (SCCmec) typing.
  • Pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) for genetic analysis.

Main Results:

  • MRSA prevalence rose from 29% in 1997 to 74% in 2002.
  • 91% of MRSA isolates harbored SCCmec type IV.
  • Two major MRSA clonal groups were identified.
  • One clonal group matched the MRSA strain from a 2002 Los Angeles County jail outbreak.

Conclusions:

  • There was a substantial increase in MRSA among San Francisco jail inmates during the study period.
  • SCCmec type IV MRSA strains, linked to outbreaks, are prevalent in this population.
  • Genetic surveillance is crucial for tracking and controlling MRSA transmission in correctional facilities.

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