Antimicrobial Resistance Profiles of Listeria Species Recovered from Retail Outlets in Gauteng Province, South Africa

• Published in: Journal of food protection Vol. 87; no. 8; p. 100322
• Main Authors: Gana, James, Gcebe, Nomakorinte, Moerane, Rebone, Ngoshe, Yusuf, Tshuma, Takula, Moabelo, Khomotso, Adesiyun, Abiodun
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.08.2024; Elsevier
• Subjects: Antibiograms; Beef products, retail outlets; Gauteng Province, South Africa; Listeria spp; Gauteng Province, South Africa; Antibiograms; Beef products, retail outlets; Listeria spp
• ISSN: 0362-028X; 1944-9097; 1944-9097
• DOI: 10.1016/j.jfp.2024.100322

•Antimicrobial resistance (AMR) of three Listeria species from beef products in South Africa was determined.•Prevalence of AMR was low for gentamycin (2.7%) and sulfamethoxazole-trimethoprim (3.6%).•Multidrug-resistant frequencies were 75.7% (L. monocytogenes) and 61.5% (L. innocua).•AMR was affected by the location, types of outlet and beef products, and serogroups.•High AMR prevalence in L. monocytogenes isolates may pose therapeutic implications. The study determined the antimicrobial resistance (AMR) profiles of Listeria spp. (L. monocytogenes, L. innocua, and L. welshimeri) recovered from beef and beef products sold at retail outlets in Gauteng Province, South Africa. A total of 112 isolates of Listeria spp., including L. monocytogenes (37), L. innocua (65), and L. welshimeri (10), were recovered from beef and beef products collected from 48 retail outlets. Listeria spp. was recovered by direct selective plating following selective enrichment, and PCR was used to confirm and characterize recovered isolates. The disc diffusion method determined the resistance to 16 antimicrobial agents. All 112 isolates of Listeria spp. exhibited resistance to one or more antibiotics (P < 0.05). The prevalence of AMR in Listeria isolates was high for nalidixic acid (99.1%) and cefotaxime (80.4%) but low for gentamycin (2.7%), sulfamethoxazole-trimethoprim (3.6%), azithromycin (5.4%), and doxycycline (6.3%). Overall, for the three species of Listeria, the prevalence of resistance varied significantly only for streptomycin (P = 0.016) and tetracycline (P = 0.034). Multidrug-resistant isolates were detected in 75.7% (28/37), 61.5% (40/65), and 80% (8/10) isolates of L. monocytogenes, L. innocua, and L. welshimeri, respectively. The prevalence of AMR was significantly affected by the location and size of retail outlets, type of beef and beef products, and serogroups of L. monocytogenes. The high prevalence of AMR, particularly among the L. monocytogenes isolates, poses potential therapeutic implications for human consumers of contaminated beef products. There is, therefore, a need to regulate and enforce the use of antimicrobial agents in humans and animals in South Africa.