Characterization of Staphylococcus aureus Isolated from Food Products in Western Algeria

Abstract

The current study aimed to characterize Staphylococcus aureus isolates from foodstuffs collected from western Algeria. A total of 153 S. aureus isolates from various raw and processed foods were obtained and identified using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Isolates were characterized by antimicrobial susceptibility testing and toxin gene detection. Methicillin-resistant Staphylococcus aureus (MRSA) isolates were identified by detection of the mecA gene and characterized by staphylococcal cassette chromosome mec (SCCmec) typing. We found that 30.9% (153/495) of food samples were contaminated with S. aureus. Thirty-three (21.5%) S. aureus isolates were identified as MRSA, and 16.9% (26/153) carried the mecA gene. Three SCCmec types were identified of which type IV was the most common (69.2%) followed by type V (15.3%) and type II (7.6%). Two MRSA isolates were not typable with SCCmec typing. None of the examined isolates harbored mecC. Furthermore, 14.3% (22/153) of the isolates were toxigenic S. aureus. The cytotoxin gene pvl was detected in 11.1% of the S. aureus isolates. This gene was more commonly detected (76.4%) in MRSA isolates than in methicillin-suceptible Staphylococcus aureus (MSSA) isolates. The tsst-1 gene coding for toxic shock syndrome toxin was isolated rarely (3.2%) and only in MSSA isolates. According to disk diffusion test results, 70 isolates were resistant to only one antimicrobial drug, and 51 (33.3%) isolates were multidrug resistant. Other 32 isolates were susceptible to all antibiotics. Our study highlights, for the first time, a high prevalence of multidrug-resistant S. aureus isolates carrying pvl or tsst-1 found in food products in Algeria. The risk of MRSA transmission through the food chain cannot be disregarded, particularly in uncooked foods.

Enterotoxin genes and antimicrobial resistance in Staphylococcus aureus isolated from food products in Algeria

“…In our study, the S. aureus contamination rate was lower than previously observed by Chaalal et al (2018) in Algeria. These authors reported a prevalence of 30Á9% out of 495 analysed samples, including raw and processed foods.…”

“…In Algeria, the proportion of MRSA demonstrated a high increase in the community and healthcare settings; the European clone ST80-IV, producer of the Panton-Valentine Leukocidin (PVL), has being detected (Antri et al 2011;Djahmi et al 2013;Chaalal et al 2018). A previous study of our group (Titouche et al 2019) was focusing on analysing dairy products obtained in 2014-2015, in which MRSA was isolated from some raw milk and acidified milk samples.…”

Phenotypic and Molecular Detection of Biofilm Formation in Staphylococcus aureus Isolated from Different Sources in Algeria

“…In Algeria, pathogenicity and antimicrobial resistance of staphylococci were investigated in clinical and food samples [21][22][23]. However, the biofilm-forming ability of Staphylococcus isolates and their genetic determinants were rarely evaluated in Algeria [24].…”

Molecular typing, phenotypic and genotypic assessment of antibiotic resistance and virulence factors amongst the Staphylococcus aureus bacteria isolated from raw chicken meat

“…Considering the over than 80% similarity, 36 S. aureus isolates were classi ed in 9 different pro les with 43 to 100% similarities. Isolates No 2,11,20,24,35,5,12,13 and 36 were classi ed in diverse pro les. The lowest similarity (43%) was found for isolates No 20, 11, 2 and 24.…”

“…Some potential virulence factors are accompanied in the pathogenesis of clinical infections and in some cases foodborne diseases caused by S. aureus [8,11]. Toxic shock syndrome toxin-1 (tsst-1), coagulase encoding gene (coa), exfoliative toxins A and B (eta and etb) and clumping factor (clfA) are frequently detected in S. aureus strains isolated from human clinical infections and foodstuffs [8,11,12].…”