Antibiotic Resistance in Staphylococcus aureus from Poultry and Poultry Products in uMgungundlovu District, South Africa, Using the Farm to Fork Approach

Background: This study determined the prevalence and antibiotic susceptibility profiles of Staphylococcus aureus isolated from selected critical control points (farm, transport, abattoir, and retail product) in an intensive poultry production system in the uMgungundlovu District, South Africa, using the farm to fork approach. Materials and Methods: Three hundred eighty-four samples from poultry and poultry products were examined across the farm to fork continuum for S. aureus using selective media, biochemical tests, and API Staph kit and confirmed by polymerase chain reaction identification of the nuc gene. Antibiotic susceptibility testing of the isolates was determined by the Kirby-Bauer disc diffusion method to 19 antimicrobials and to vancomycin by the broth microdilution technique. Results: The overall prevalence rate of S. aureus was 31.25% (n = 120/384), distributed across the continuum: farm site (40), transport (15), abattoir (30), and retail point (35). The isolates were resistant to tetracycline (61.67%), penicillin G (55.83%), erythromycin (54.17%), clindamycin (43.33%), doxycycline (36.67%), ampicillin (34.17%), moxifloxacin (30.83%), amikacin (30.83%), trimethoprim-sulfamethoxazole (30.00%), and levofloxacin (23.33%). A 100% susceptibility to tigecycline, teicoplanin, vancomycin, nitrofurantoin, chloramphenicol, and linezolid was observed in all isolates. The rate of multidrug resistance and the multiple antibiotic resistance index of the strains were 39.17% and 0.23%, respectively. The isolates showed similar patterns of resistance to commonly used growth promoters and antibiotics in veterinary and human medicine belonging to the same class. Conclusion: It is evident that the different antibiotics and growth promoters used in poultry production are exerting selection pressure for the emergence and co-selection of antibiotic-resistant bacteria in the production system, necessitating efficient antibiotic stewardship guidelines to streamline their use.