Related Experiment Video
Updated: May 22, 2026
Chronic Salmonella Infected Mouse Model
Published on: May 31, 2010
Virulence of 32 Salmonella strains in mice
Matthew C Swearingen1, Steffen Porwollik, Prerak T Desai
1Department of Microbiology, The Ohio State University, Columbus, Ohio, USA.
Abstract:
Virulence and persistence in the BALB/c mouse gut was tested for 32 strains of Salmonella enterica for which genome sequencing is complete or underway, including 17 serovars within subspecies I (enterica), and two representatives of each of the other five subspecies. Only serovar Paratyphi C strain BAA1715 and serovar Typhimurium strain 14028 were fully virulent in mice. Three divergent atypical Enteritidis strains were not virulent in BALB/c, but two efficiently persisted. Most of the other strains in all six subspecies persisted in the mouse intestinal tract for several weeks in multiple repeat experiments although the frequency and level of persistence varied considerably. Strains with heavily degraded genomes persisted very poorly, if at all. None of the strains tested provided immunity to Typhimurium infection. These data greatly expand on the known significant strain-to-strain variation in mouse virulence and highlight the need for comparative genomic and phenotypic studies.
Insights
Salmonella enterica strains show varied virulence and persistence in mouse guts. Genome degradation correlated with poor persistence, indicating significant strain differences.
Area of Science:
- Microbiology
- Genomics
- Immunology
Background:
- Salmonella enterica encompasses diverse subspecies with varying pathogenic potential.
- Understanding strain-level variation in virulence and gut persistence is crucial for controlling salmonellosis.
Purpose of the Study:
- To evaluate the virulence and gut persistence of 32 Salmonella enterica strains across six subspecies in a BALB/c mouse model.
- To investigate the relationship between genome integrity and persistence.
Main Methods:
- Infection of BALB/c mice with 32 Salmonella enterica strains representing six subspecies.
- Assessment of bacterial load in the gut to determine virulence and persistence over several weeks.
- Correlation of persistence data with available genomic information.
Main Results:
- Only Salmonella enterica serovar Paratyphi C strain BAA1715 and serovar Typhimurium strain 14028 exhibited full virulence.
- Three atypical Enteritidis strains were avirulent but two showed efficient persistence.
- Most strains persisted for weeks, with considerable variation in frequency and level; degraded genomes correlated with poor persistence.
- No tested strain conferred immunity against subsequent Salmonella Typhimurium infection.
Conclusions:
- Significant strain-to-strain variation exists in Salmonella enterica virulence and persistence in the mouse gut.
- Genome degradation is associated with reduced persistence.
- Comparative genomic and phenotypic studies are essential for a comprehensive understanding of Salmonella pathogenesis.
