PREVALENCE OF DRUG RESISTANCE AND VIRULENCE FEATURES IN Salmonella spp. ISOLATED FROM FOODS ASSOCIATED OR NOT WITH SALMONELLOSIS IN BRAZIL

Abstract

Salmonella is the most common etiological agent of cases and outbreaks of foodborne diarrheal illnesses. The emergence and spread of Salmonella spp., which has become multi-drug resistant and potentially more pathogenic, have increased the concern with this pathogen. In this study, 237 Salmonella spp., associated or not with foodborne salmonellosis in Brazil, belonging mainly to serotype Enteritidis, were tested for antimicrobial susceptibility and the presence of the virulence genes spvC, invA, sefA and pefA. Of the isolates, 46.8% were sensitive to all antimicrobials and 51.9% were resistant to at least one antimicrobial agent. Resistance to more than one antimicrobial agent was observed in 10.5% of the strains. The highest rates of resistance were observed for streptomycin (35.9%) and nalidixic acid (16.9%). No strain was resistant to cefoxitin, cephalothin, cefotaxime, amikacin, ciprofloxacin and imipenem. The invA gene was detected in all strains. Genes spvC and pefA were found in 48.1% and 44.3% of strains, respectively. The gene sefA was detected in 31.6% of the strains and only among S. Enteritidis. Resistance and virulence determinants were detected in Salmonella strains belonging to several serotypes. The high rates of antibiotic-resistance in strains isolated from poultry products demonstrate the potential risk associated with the consumption of these products and the need to ensure good food hygiene practices from farm to table to reduce the spread of pathogens relevant to public health.

Fresh Farm Vegetables as a Source of Virulent Drug Resistant Salmonella enterica

“…These genes were also screened by other researchers in meat, poultry and food samples (El Allaoui et al, 2013;Karmi, 2013;Rowlands et al, 2014) which are in substantial agreement with our findings.…”

Serotypes and antimicrobial resistance profiles of Salmonella isolated from fresh beef processing and chilled fresh beef samples produced and marketed in the metropolitan region of Cuiab, in the State of Mato Grosso, Brazil

“…Non-typhoid Salmonella strains, including serotypes S. Anatum, S. Infantis, and S. Panama, can cause gastroenteritis, which can progress to systemic infections (bacteremias and meningitis) (Huang et al, 2013;Rowlands et al, 2014). These strains may display an invasive capacity, a characteristic of multi-resistance to antimicrobial drugs, which are genes encoded capacity that may potentiate their persistence in the organism and hence, their pathogenicity (Ribeiro et al, 2007;Huang et al, 2013).…”

Salmonella Panama: Genetic Diversity of the Isolates Collected from Human and Non-human Sources

“…The detection of virulence-related genes showed that all 44 isolates were positive for invA (invasion), fimA and agfA (adherence), and sfbA (component of the iron transport system) genes and negative for spvC (motility) and fliC (adherence and invasion) genes. Only one isolate (231/2001) was negative for phoP/Q (intra-macrophage survival),while slyA (a virulenceassociated transcriptional regulator) was detected in 12 isolates obtained from food (7), estuarine water (2), and rectal swab from a lizard (3). Salmonella infections show multifactorial pathogenesis and that multiple virulence genes may be involved.…”

“…The ability of Salmonella spp. to cause disease can be attributed to an array of virulence genes located in the chromosomes or in large virulence-associated plasmids 3 . Several factors related to the virulence of Salmonella spp.…”