Managing Antibiotic Residues In Hospital Wastewater: A Major Environmental Lever In The Fight Against The Transmission Of AntibioticResistant Strains In Lubumbashi (Drc)

Abstract

Background: Antimicrobial resistance (AMR) is a global public health threat, with hospital wastewater increasingly recognized as an environmental reservoir of antibiotic residues, resistant bacteria, and resistance genes. In resource-limited settings such as Lubumbashi (Democratic Republic of Congo), inadequate wastewater treatment may contribute to environmental dissemination of resistant strains. Objective: To evaluate hospital effluent management and assess its role in reducing the risk of environmental transmission of antibiotic-resistant bacteria. Methods: An analytical cross-sectional study was conducted in public and private hospitals in Lubumbashi. Data were collected on antibiotic disposal practices, wastewater treatment systems, environmental monitoring, and staff training. An Effluent Management Score (EMS) was developed. Bivariate analyses and multivariate logistic regression were performed to identify factors associated with high environmental transmission risk. Model performance was assessed using ROC curve analysis. Results: Fewer than 25% of hospitals had specific wastewater treatment systems, and environmental monitoring was performed in less than 10% of facilities. Lack of wastewater treatment (OR = 4.52; p < 0.001), absence of an internal treatment plant (OR = 3.78; p < 0.001), uncontrolled antibiotic disposal (OR = 3.21; p = 0.004), lack of environmental monitoring (OR = 4.01; p < 0.001), and absence of staff training (OR = 2.87; p = 0.008) were significantly associated with high risk. Each one-point increase in EMS reduced risk by 38% (aOR = 0.62; p < 0.001). The model demonstrated good discrimination (AUC = 0.83). Conclusion: Poor hospital wastewater management significantly increases environmental AMR transmission risk. Strengthening effluent treatment, monitoring, and staff training represents a strategic environmental lever within a One Health framework. Keywords: Antimicrobial resistance; Hospital wastewater; Antibiotic residues; Environmental transmission; One Health