Antibiotic-Resistant Salmonella in Animal Products Jeopardize Human Health

Despite the significance of antibiotics in treating bacterial infections, antibiotic resistance is continuously increasing, thus posing a significant threat. In addition to strains resistant to individual drugs, multidrug-resistant (MDR) and pandrug resistant strains, which are resistant to all antibiotics, are emerging. Salmonella, a primary cause of global foodborne illness, is often transmitted through animal products. Antibiotic treatment is crucial for immunocompromised individuals, such as older adults and patients with weakened immune systems, due to their increased susceptibility to severe effects. MDR Salmonella, which can arise following antibiotic use in food animals, may transfer to humans, leading to significant health challenges. The emergence of Salmonella strains resistant to carbapenems, often considered a last-resort antibiotic class, is particularly concerning. Salmonella neutralizes antibiotics through mechanisms, such as horizontal gene transfer via plasmids, efflux/influx system regulation, and enzyme production that deactivate or alter antibiotics. The rise of mega plasmids in Salmonella is particularly alarming, as it may enable resistance to a broader range of antibiotics. This review summarizes the current state of the growing threat of MDR Salmonella and underscores the urgent need for a coordinated response.