Emergence of Multidrug-Resistant and Biofilm-Producing Staphylococcus aureus from Raw Poultry in Algeria: Implications for Public Health.

Staphylococcus aureus is a common foodborne pathogen, posing significant concern due to the emergence of its multidrug-resistant (MDR) strains. The aim of this study was to assess the antibiotic resistance profiles in S. aureus isolated from raw poultry, the associated resistance genes, and their ability to form biofilms. S. aureus was isolated and identified using conventional microbiological methods. Antimicrobial susceptibility profiles were assessed using the disk diffusion method, and biofilm-forming ability was evaluated using the microtiter plate assay. The presence of antimicrobial resistance genes was determined by PCR. A total of 45 isolates were isolated. High resistance rates were observed against penicillin (88.9%), tetracycline (86.7%) and doxycycline (66.7%). Of the isolates, 71.1% were classified as multidrug-resistant (MDR) organisms, and 60% exhibited a multiple antibiotic resistance index greater than 0.2. PCR analysis revealed the presence of the resistance genes blaZ (86.7%), mecA (27.3%), tet(M) (46.2%), tet(K) (35.9%), tet(S) (59%), erm(B) (51.9%), and erm(C) (59.3%). A total of 44 isolates were biofilm producers: 46.7% were weak producers, 46.7% were moderate producers, and 4.4% were strong producers. These findings highlight a significant public health concern, emphasizing the need for stringent hygiene practices and continuous monitoring to limit the spread of resistant pathogens through the food chain.