Tandem repeat analysis for surveillance of human Salmonella Typhimurium infections

Emerg Infect Dis. 2007 Mar;13(3):388-95. doi: 10.3201/eid1303.060460.

Abstract

In Denmark, as part of the national laboratory-based surveillance system of human enteric infections, all Salmonella enterica serotype Typhimurium isolates are currently subtyped by using phage typing, antimicrobial resistance profiles, and pulsed-field gel electrophoresis (PFGE). We evaluated the value of real-time typing that uses multiple-locus variable-number tandem-repeats analysis (MLVA) of S. Typhimurium to detect possible outbreaks. Because only a few subtypes identified by PFGE and phage typing account for most infections, we included MLVA typing in the routine surveillance in a 2-year period beginning December 2003. The 1,019 typed isolates were separated into 148 PFGE types and 373 MLVA types. Several possible outbreaks were detected and confirmed. MLVA was particularly valuable for discriminating within the most common phage types. MLVA was superior to PFGE for both surveillance and outbreak investigations of S. Typhimurium.

Publication types

  • Comparative Study

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacteriophage Typing
  • Denmark / epidemiology
  • Disease Outbreaks*
  • Electrophoresis, Gel, Pulsed-Field
  • Humans
  • Minisatellite Repeats
  • Molecular Epidemiology / methods
  • Salmonella Infections / epidemiology*
  • Salmonella typhimurium / classification
  • Salmonella typhimurium / drug effects
  • Salmonella typhimurium / genetics*
  • Sentinel Surveillance
  • Species Specificity
  • Tandem Repeat Sequences / genetics*

Substances

  • Anti-Bacterial Agents