Phenotypic and genotypic characterization of Staphylococcus aureus, including MRSA and PVL-positive isolates, in Egyptian fruit bats

Background Bats are widely distributed mammals capable of harboring diverse pathogens, including antimicrobial-resistant bacteria. Staphylococcus aureus ( S. aureus ), particularly methicillin-resistant S. aureus (MRSA), poses a significant public health concern. This study aimed to investigate the occurrence, antimicrobial resistance profile, and presence of the Panton–Valentine leukocidin ( pvl ) virulence gene of S. aureus in Egyptian fruit bats. Methods Fifty Egyptian fruit bats were captured using mist nets at both foraging and roosting sites and morphologically identified. A total of 150 samples (intestinal contents, oral swabs, and skin swabs) were collected for bacteriological examination. S. aureus isolates were confirmed by Gram staining, catalase test, and coagulase test. Genomic DNA was extracted for molecular identification using PCR targeting the 16S rRNA and nuc genes. Antimicrobial susceptibility testing was conducted using the disk diffusion method. PCR was additionally used to screen for methicillin resistance genes ( mecA and mecC ) and the pvl virulence gene. Results At the sample level, 67 of 150 samples (44.7%) were confirmed as S. aureus , while 42 of 50 bats (84.0%) tested positive at the bat level. The highest prevalence was observed in skin swabs (56.0%), followed by intestinal contents (40.0%) and oral swabs (38.0%). Eighteen isolates (26.9%) were classified as MRSA, and five isolates (7.5%) were multidrug-resistant (MDR), all of which were also MRSA. PCR analysis detected the mecA gene in 7 of the 18 (38.9%) MRSA isolates, while the mecC gene was not detected in any sample (0.0%). The pvl gene was identified in 6 of 67 isolates (9.0%). MRSA isolates exhibited diverse antimicrobial resistance patterns, with 61.1% demonstrating a multiple antimicrobial resistance index (MARI) value ≥ 0.2. Conclusion This study provides evidence of S. aureus carriage in Egyptian fruit bats, including MRSA and PVL-positive isolates, some of which were multidrug-resistant. These findings suggest that bats may serve as ecological carriers of antimicrobial-resistant and virulent bacteria, highlighting the importance of wildlife surveillance within a One Health framework.