An Arsenal of Multiple Antimicrobial Resistance, Toxins, and Virulence Factors in Gram-Negative Bacterial Isolates from Food - A Formidable Combination!

Background: Infectious diseases caused by pathogenic members of the family Methods: Bacteria were isolated from commercial dairy foods. These were cultured in appropriate media for identification at the family level ( Results: Twenty Gram-negative bacteria isolated from the foods were found to be resistant to almost all antimicrobials belonging to the phenicol, aminoglycoside, fluoroquinolone, monobactam, and β-lactam classes. All of them were multiple-drug-resistant. The resistance to the β-lactams was due to the production of β-lactamases and were also mostly resistant to some of the β-lactam/β-lactamase inhibitor combinations. Some isolates also contained toxins. Conclusion: This small-scale study demonstrated the presence, in the isolates, of high levels of virulence factors and resistance to major antimicrobials that are in clinical use. Most treatment being empirical, there can be not only a high degree of treatment failure but also the likelihood for further development and dissemination of antimicrobial resistance. Since dairy foods are animal products, there is an urgent need to control animal-food-human transmission mechanisms, restrict antimicrobial use in animal agriculture, and improve clinical treatment from the usual empirical treatment to more targeted and effective treatment.