Prevalence and Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Retail Chicken Meat in Chennai, India

The present study was conducted to evaluate the prevalence of S. aureus in retail chicken meat marketed in Chennai, Tamil Nadu and to determine the antimicrobial susceptibility pattern of these isolates. A total of 120 meat samples were collected from different retail outlets and it was observed that 66.67 (80/120) per cent of the samples were positive for the presence of S. aureus based on biochemical characterization. The S. aureus count in chicken meat samples (160) ranged from 2.8 × 10² to 1.5 × 10⁴ CFU/g with an overall average of 2.98 × 10³ CFU/g. Antimicrobial susceptibility testing of these isolates against 16 antimicrobials revealed that all the isolates were resistant to Ampicillin (100%) followed by Tetracycline (87.50%), Amoxicillin (77.50%), Erythromycin (72.50%), Polymyxin-B (70%), Cefoxitin (67.50%), Novobiocin (67.50%), Oxacillin (65%) and Ciprofloxacin (50%). Majority of the chicken isolates were sensitive to Gentamicin (92.50%), followed by Vancomycin (87.50%), Chloramphenicol (82.50%), Neomycin (80%), Kanamycin (77.50%), Co-trimoxazole (62.50%) and Methicillin (55%). Results of Multiple Antibiotic Resistance (MAR) Index revealed that 99.38 per cent of the isolates (119/120) had MAR index of above 0.2 and only one isolate had index below 0.2. The results clearly indicated higher prevalence of multidrug resistant S. aureus in retail Chicken meat from public health point and the level of hygiene prevalent in these outlets.