Antimicrobial resistance, plasmid, virulence, multilocus sequence typing and pulsed-field gel electrophoresis profiles of Salmonella enterica serovar Typhimurium clinical and environmental isolates from India

Salmonella isolates were recovered from bulk tank milk as part of the National Animal Health Monitoring System (NAHMS) Dairy 2002 and 2007 surveys. In-line milk filters were also tested in the 2007 survey. The objective of this study was to determine the prevalence of antimicrobial resistance among Salmonella enterica isolates from bulk milk and milk filters in the NAHMS Dairy 2002 and 2007 surveys and to further characterize resistant isolates. Susceptibilities to 15 antibiotics were determined for 176 Salmonella isolates of 26 serotypes using an automated antimicrobial susceptibility system. Resistant isolates were screened by PCR for the presence of the extended-spectrum β-lactamase (blaCMY) gene and class I integrons and further characterized by pulsed-field gel electrophoresis. Thirty isolates (17.0%) representing six S. enterica serotypes exhibited resistance to at least one antimicrobial agent (serotypes Newport [14 of 14 isolates exhibited resistance], Dublin [7 of 7], Typhimurium [3 of 5], Kentucky [4 of 22], Anatum [1 of 13], and Infantis [1 of 2]). Twenty isolates (11.4%), including all 14 Newport, 3 Dublin, 2 Typhimurium, and 1 Infantis isolate, displayed the typical multidrug-resistant, blaCMY-positive (MDR-AmpC) phenotype which included resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide, and tetracycline, plus resistance to amoxicillin–clavulanic acid and extended-spectrum cephalosporins. Five of the MDR-AmpC isolates carried class I integrons (2.8%). Two-enzyme (XbaI and BlnI) pulsed-field gel electrophoresis discerned clades within serotypes and, together with the resistance profiles, identified strains that appeared to have persisted temporally and geographically. These results suggest that there is a low but appreciable risk of infection with MDR Salmonella from consumption of nonpasteurized milk and dairy products.

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Prevalence and Genetic Properties of Salmonella enterica Serovar Typhimurium Definitive Phage Type 104 Isolated from Rattus norvegicus and Rattus rattus House Rats in Yokohama City, Japan

Applied and Environmental Microbiology ◽

10.1128/aem.02465-06 ◽

2007 ◽

Vol 73 (8) ◽

pp. 2624-2630 ◽

Cited By ~ 22

Author(s):

Eiji Yokoyama ◽

Soichi Maruyama ◽

Hidenori Kabeya ◽

Siro Hara ◽

Shin Sata ◽

...

Keyword(s):

Rattus Norvegicus ◽

Gel Electrophoresis ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Phage Type ◽

Rattus Rattus ◽

Pulsed Field Gel Electrophoresis ◽

Intestinal Contents ◽

Serovar Typhimurium ◽

J 24

ABSTRACT Salmonella enterica serovar Typhimurium was isolated from the intestinal contents of Rattus rattus and Rattus norvegicus house rats captured at two buildings, designated buildings J and YS, in Yokohama City, Japan. From October 1997 to September 1998, 52 of 339 (15.3%) house rats were found to carry Salmonella serovar Typhimurium definitive phage type 104 (DT104). In building J, 26 of 161 (16.1%) house rats carried DT104 over the 1-year study period, compared to 26 of 178 (14.6%) rats in building YS. The isolation rates of DT104 from R. rattus and R. norvegicus were similar in the two buildings. Most DT104 strains from building J (24 of 26) showed resistance to ampicillin, chloramphenicol, streptomycin, sulfisoxazole, and tetracycline and contained both the 1.0- and 1.2-kbp integrons, carrying genes pse1, pasppflo-like, aadA2, sulI, and tet(G). All DT104 strains from building YS were resistant to ampicillin and sulfisoxazole, and had the 1.2-kbp integron carrying pse1 and sulI. Cluster analysis of pulsed-field gel electrophoresis patterns of BlnI-digested DT104 DNAs showed that 22 of 26 DT104 strains from building J and 24 of 26 strains from building YS could be grouped into separate clusters each specific for the building origin. These results indicated that DT104 strains were prevalent in house rat colonies in each building and suggest that house rats may play an important role in the epidemiology of DT104.

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Subtyping of Salmonella Enterica Serovar Typhimurium from Clinical Samples by Multiple-Locus Variable-Number Tandem Repeat Analysis and Pulsed-Field Gel Electrophoresis

Microbiology & Infectious Diseases ◽

10.33425/2639-9458.1069 ◽

2019 ◽

Vol 3 (4) ◽

Author(s):

Sana A Khan ◽

Steven Foley ◽

Rossina Stefanova ◽

Mohamed S Nawaz ◽

Carl E Cerniglia ◽

...

Keyword(s):

Tandem Repeat ◽

Gel Electrophoresis ◽

Salmonella Enterica Serovar Typhimurium ◽

Variable Number Tandem Repeat ◽

Variable Number ◽

Pulsed Field Gel Electrophoresis ◽

Clinical Samples ◽

Pulsed Field ◽

Repeat Analysis ◽

Serovar Typhimurium

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Pulsed-Field Gel Electrophoresis Supports the Presence of Host-Adapted Salmonella enterica subsp. enterica Serovar Typhimurium Strains in the British Garden Bird Population

Applied and Environmental Microbiology ◽

10.1128/aem.00131-11 ◽

2011 ◽

Vol 77 (22) ◽

pp. 8139-8144 ◽

Cited By ~ 25

Author(s):

Becki Lawson ◽

Laura A. Hughes ◽

Tansy Peters ◽

Elizabeth de Pinna ◽

Shinto K. John ◽

...

Keyword(s):

Gel Electrophoresis ◽

Salmonella Enterica ◽

Phage Type ◽

Pulsed Field Gel Electrophoresis ◽

Phage Typing ◽

Molecular Technique ◽

Content Type ◽

Pulsed Field ◽

Phage Types ◽

Serovar Typhimurium

ABSTRACTSalmonellosis is a frequently diagnosed infectious disease of passerine birds in garden habitats within Great Britain with potential implications for human and domestic animal health. Postmortem examinations were performed on 1,477 garden bird carcasses of circa 50 species from England and Wales, 1999 to 2007 inclusive. Salmonellosis was confirmed in 263 adult birds of 10 passerine species in this 11-year longitudinal study. A subset of 124 fully biotypedSalmonella entericasubsp.entericaserovar Typhimurium isolates was examined using pulsed-field gel electrophoresis to investigate the hypothesis that these strains are host adapted and to determine whether this molecular technique offers greater resolution in understanding the epidemiology ofSalmonellaTyphimurium infection than phage typing alone. For the two most common phage types, definitive type (DT) 40 and DT56v, which together accounted for 97% (120/124) of isolates, pulsed-field gel electrophoresis groupings closely correlated with phage type with remarkably few exceptions. A high degree of genetic similarity (>90%) was observed within and between the two most common pulsed-field gel electrophoresis groups. No clustering or variation was found in the pulsed-field gel electrophoresis groupings by bird species, year, or geographical region beyond that revealed by phage typing. These findings support the hypothesis that there are currently two host-adaptedSalmonellaphage types,S. Typhimurium DT40 and DT56v, circulating widely in British garden birds and that the reservoir of infection is maintained within wild bird populations. Large-scale multilocus sequence typing studies are required to further investigate the epidemiology of this infection.

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Fecal Excretion of Salmonella entericaSerovar Typhimurium Following a Food-Borne Outbreak

Journal of Clinical Microbiology ◽

10.1128/jcm.38.9.3495-3497.2000 ◽

2000 ◽

Vol 38 (9) ◽

pp. 3495-3497 ◽

Cited By ~ 24

Author(s):

Toshiyuki Murase ◽

Mikiko Yamada ◽

Tetsunori Muto ◽

Akiyoshi Matsushima ◽

Shiro Yamai

Keyword(s):

Gel Electrophoresis ◽

Salmonella Enterica ◽

Pulsed Field Gel Electrophoresis ◽

Fecal Excretion ◽

Antimicrobial Drugs ◽

Pulsed Field ◽

Infected People ◽

The People ◽

Food Borne ◽

Serovar Typhimurium

Fecal excretion of Salmonella enterica serovar Typhimurium organisms was observed in patients and in people not showing symptoms who were involved in an outbreak of food-borne infection with this organism. Excretion of organisms was prolonged in the patients who were given antimicrobial drugs compared with those who were not. The isolates were indistinguishable by their pulsed-field gel electrophoresis patterns and biotyping from the strain recovered from the roast pork that had been consumed by all of the people. This indicates that these isolates obtained from the infected people had originated in the contaminated pork.

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