Work

Dissemination of antibiotic-resistant enterobacteriaceae from hospital wastewater in Gabon: implications for the one health strategy

Year: 2026

Type: article

Abstract: INTRODUCTION: The proliferation of Enterobacteriaceae exhibiting a multidrug-resistant phenotype in aquatic ecosystems is a major concern for global public health. In Gabon, the lack of adequate pre-treatment systems means that hospital wastewater acts as a critical reservoir associated with the spread of these pathogens into surface waters. This study aimed to characterise the bacterial load and phenotypic resistance profiles of Enterobacteriaceae isolated from the effluents of eleven Gabonese hospitals, whilst assessing the environmental factors associated with their presence. METHODOLOGY: 2. Susceptibility to 19 antibiotics was determined using the standardized phenotypic disk diffusion method (Kirby-Bauer). RESULTS: The bacterial load was significantly higher in hospital wastewater (up to 1.68 × 10⁸ CFU/mL) than in surface water. Univariate analysis revealed that the presence of debris (p = 0.003), foam (p = 0.016) and a greyish or brownish colouration of the water (p = 0.028) were visual indicators significantly markers of environmental pollution rather than confirmed causal factors. All confirmed Enterobacteriaceae isolates (n = 113) exhibited a multidrug-resistant phenotype, with rates of resistance to beta-lactams exceeding 95%. The genus Escherichia (n = 45) was predominant. CONCLUSION: This observational study demonstrates that untreated hospital wastewater in Gabon is a significant source of microbiological pollution. Environmental visual indicators are useful for identifying areas with high bacterial loads. It is necessary to develop pre-treatment infrastructure to mitigate the associated environmental and health risks.

Source: BMC Microbiology

DOI: 10.1186/s12866-026-05384-y