Environmental propagation of antibiotic resistance: The roles of rivers and dams—an underexplored dimension of a global crisis

Antibiotic resistance is inevitable; thus, better understanding the origins and the sources that support the spread of resistance genes among microorganisms is crucial. The rapid spread of resistance elements among the most prevalent bacterial pathogens poses an active threat to public health.
Indeed, such threat will continue looming if experts fail to control the skyrocketing dissemination of antibiotics into the natural environment, through mass human migrations, or within clinical, husbandry, or veterinary settings. Any policy governing antibiotic administration in human or veterinary medicine must consider the transmission of antibiotic-resistant microorganisms between environmental sources and humans or animals. In this context, dams and rivers represent two major environmental sources of antibiotic-resistant bacteria, acting as reservoirs and conduits for resistance genes via horizontal gene transfer. In such a scenario, routine surgeries (e.g., cesarean sections, joint replacements) would become high-risk procedures due to the absence of prophylactic antibiotics; bacterial pneumonia, once easily cured, would revert to its historical status as a leading cause of death; and the management of immunocompromised patients (transplant recipients, cancer patients undergoing chemotherapy) would be severely compromised. The emerging high incidence of antibiotic-resistant or multidrug-resistant bacterial infections, coupled with the extant arsenal of antibacterial drugs that have waning values and applicabilities, forewarns of an imminent and unknown post-antibiotic era—a time when even common infections may become untreatable, underscoring the urgent need for global surveillance and stewardship.