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Salmonella typhimurium bacteremia: association with the virulence plasmid

J Fierer1, M Krause, R Tauxe

  • 1Department of Medicine, University of California, San Diego, School of Medicine.

The Journal of Infectious Diseases
|September 1, 1992
PubMed

Insights

Virulence plasmids significantly boost Salmonella growth and survival. This study found these plasmids are common in human Salmonella bacteremia blood isolates, suggesting their importance in human disease.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Virulence plasmids enhance Salmonella growth and reduce lethal doses in mice.
  • Their role in human Salmonella bacteremia is not well understood.

Purpose of the Study:

  • To investigate the prevalence and significance of virulence plasmids in human Salmonella typhimurium infections.
  • To determine if virulence plasmids contribute to Salmonella bacteremia in humans.

Main Methods:

  • Analysis of Salmonella typhimurium isolates from blood and fecal samples in California.
  • Use of colony blotting with a labeled probe from the Salmonella dublin virulence plasmid.

Main Results:

  • The virulence plasmid probe hybridized with 42% of fecal isolates.
  • The probe hybridized with 76% of blood isolates, indicating higher prevalence in bacteremia.

Conclusions:

  • Virulence plasmids are frequently present in Salmonella typhimurium causing human bacteremia.
  • This provides the first evidence of their importance in the pathogenesis of human Salmonella bacteremia.

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