Antimicrobial resistance in raw cow's milk in Bwegera, Democratic Republic of the Congo: implications for food safety.

Abstract

Antibiotic resistance poses a significant threat to global food safety, particularly in unpasteurised dairy products. In the locality of Bwegera (South Kivu, DRC), livestock management practices promote the emergence of resistant bacterial strains, constituting a risk to public health. This study aimed to assess the resistance profile of enteropathogenic bacteria isolated from raw cow's milk in Bwegera, and to identify farming practices associated with this antibiotic resistance. A total of 144 milk samples were collected from 12 farms and analyzed following the standards of the International Organization for Standardization and the Clinical and Laboratory Standards Institute / European Committee on Antimicrobial Susceptibility Testing to identify bacteria belonging to the Enterobacteriaceae family and to determine their susceptibility to various antibiotics. The analysis revealed a high prevalence of Escherichia coli (52.8%), followed by Klebsiella pneumoniae (10.4%) and Citrobacter diversus (10.4%). Resistance was notably high for tetracyclines and vancomycin, affecting up to 95% of isolates, while amikacin remained fully effective (100% of isolates susceptible). Farming practices were characterised by frequent self-medication (83.3%) and a lack of awareness regarding antibiotic resistance (66.7%). Three farmer profiles were identified: one well-trained group misusing antibiotics, and another using antibiotics as feed additives. The majority of samples exhibited polymicrobial contamination (71.5%), with microbial loads often exceeding 300 CFU/mL. Inadequate sanitary and pharmaceutical practices foster resistant bacterial strains. Improved farmer education, stricter antibiotic regulations, and alternative interventions such as probiotics are needed within a 'One Health' framework.