Genotyping of enterotoxigenic methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Staphylococcus aureus (VRSA) among commensal rodents in North Sinai, Egypt.

AIM: This study aimed to identify genotype enterotoxigenic antimicrobial-resistant Staphylococcus aureus species, mainly methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA) among commensal rodents. METHODS AND RESULTS: A total of 280 samples were collected from nasal and mouth swabs, heart blood, intestinal content and lung tissues of 56 commensal rodents trapped from North Sinai, Egypt. Antimicrobial susceptibility testing was performed to bacteriologically identified S. aureus isolates against 15 antimicrobial agents by disc diffusion method. Detection was conducted for identifying coagulase gene (coA), antimicrobial-resistant genes (mecA and vanA/B), enterotoxigenic and virulence determinant genes (hlg, seb, sed and see) among the MRSA and VRSA isolates. RESULTS: Staphylococcus aureus species were isolated from 24 (42.86%) out of 56 rodents. Phenotypic examination revealed that all the isolates were multidrug-resistant, whereas two isolates were multiple antibiotic resistant (MAR). Out of 33 examined isolates, 33 (100%) were resistant to oxacillin and amoxicillin, 31 (93.93%) to cefoxitin and 12 (36.36%) to vancomycin. PCR assay revealed that 24 isolates revealed (100%) positivity to coA gene, 17 (70.83%) to mecA gene and 12 (50%) to vanA/B genes. Enterotoxin genes and haemolysin genes were detected among MRSA and VRSA isolates. There was a strong positive correlation between the tested antimicrobial-resistant genes and virulence genes (p > 0.05). CONCLUSIONS: This study demonstrated the occurrence of MRSA and VRSA strains among commensal rodents in North Sinai, Egypt. The detection of enterotoxigenic and virulence genes of the isolated MRSA and VRSA strains indicated the health hazards of food contamination and zoonotic infections. SIGNIFICANCE AND IMPACTS OF THE STUDY: This study emphasizes the role of commensal rodents in maintaining and disseminating multidrug-resistant MRSA and VRSA strains to the environment, animals and human beings.

oprL Gene Sequencing, Resistance Patterns, Virulence Genes, Quorum Sensing and Antibiotic Resistance Genes of XDR Pseudomonas aeruginosa Isolated from Broiler Chickens.

Background: Pseudomonas aeruginosa is incriminated in septicemia, significant economic losses in the poultry production sector, and severe respiratory infections in humans. This study aimed to investigate the occurrence, oprL sequencing, antimicrobial resistance patterns, virulence-determinant, Quorum sensing, and antibiotic resistance genes of P. aeruginosa retrieved from broiler chickens. Methods: Two hundred samples were collected from 120 broiler chickens from broiler farms at Ismailia Governorate, Egypt. Consequently, the bacteriological examination was conducted and the obtained P. aeruginosa strains were tested for oprL gene sequencing, antibiogram, and PCR screening of virulence, Quorum sensing, and antibiotic resistance genes. Results: The overall prevalence of P. aeruginosa in the examined birds was 28.3%. The oprL gene sequence analysis underlined that the tested strain expressed a notable genetic identity with various P. aeruginosa strains isolated from different geographical areas in the USA, India, China, Chile, and Ghana. PCR evidenced that the obtained P. aeruginosa strains, carrying virulence-related genes: oprL, toxA, aprA, phzM, and exoS in a prevalence of 100%, 100%, 42.5%, 33.3%, and 25.9%, respectively. Moreover, the recovered P. aeruginosa strains possessed the Quorum sensing genes: lasI, lasR, rhlI, and rhlR in a prevalence of 85.2%, 85.2%, 81.5%, and 81.5%, respectively. Furthermore, 40.7% of the isolated P. aeruginosa were XDR to seven antimicrobial classes, possessing sul1, bla TEM, tetA, bla CTX-M, bla OXA-1, and aadA1 genes. Conclusion: As we can tell, this is the first report emphasizing the evolution of XDR P. aeruginosa strains from broiler chicken in Egypt, which is supposed to be a serious threat to public health. The emerging XDR P. aeruginosa in poultry frequently harbored the oprL, toxA, and aprA virulence genes, the lasI, lasR, rhlI, and rhlR Quorum sensing genes, and the sul1, bla TEM, tetA, bla CTXM, bla OXA-1, and aadA1 resistance genes.