Phenotypic and genotypic characterization of Salmonella enterica serotype paratyphi B isolates from environmental and human sources in Galicia, Spain.
Salmonella serotype Paratyphi B isolates obtained from shellfish and human infections in Galicia (northwest Spain) from 1998 were investigated by different phenotypic and genetic methods to evaluate their systemic or enteric nature. Isolates were investigated for D-tartrate fermentation, presence of genes encoding the effector proteins sopE1 and avrA, pulsed-field gel electrophoresis profile, and antimicrobial susceptibility. Systemic variant strains (dT-) were the dominant among the marine environment isolates. All dT- isolates were sopE1 positive and avrA negative, presented an indistinguishable electrophoresis profile, and were grouped in a single cluster. More electrophoresis heterogeneity was observed among dT+ isolates. Only two isolates showed resistance to any of the 16 antibiotics included in our panel. The present study identified the marine environment as a potential natural source of systemic variant isolates of Salmonella Paratyphi B. The presence of systemic variant isolates of Salmonella Paratyphi B in the marine environment is of notable public health significance as a result of the potential risk of acquiring enteric fever linked to the consumption of raw shellfish.
Martinez-Urtaza
Jaime
J
Instituto de Acuicultura, Universidad de Santiago de Compostela, Campus Universitario Sur, 15782 Santiago de Compostela, Spain. ucmjmur@usc.es
Echeita
Aurora
A
Liebana
Ernesto
E
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016000:Cluster Analysis; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods; D004783:Environmental Microbiology; D005285:Fermentation; D005506:Food Contamination; D005516:Food Microbiology; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D010284:Paratyphoid Fever / Q000382:microbiology*; D010641:Phenotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D011634:Public Health; D012484:Salmonella paratyphi B / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012758:Shellfish / Q000382:microbiology*; D013030:Spain; D013644:Tartrates / Q000378:metabolism
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D013644:Tartrates; C029768:tartaric acid