ESBL superbacteria in fresh waters of Tungurahua: risks and regulatory gaps

Abstract

Introduction: currently, antimicrobial resistance and more specifically extended-spectrum beta-lactamase (ESBL)-producing bacteria are a growing global threat. The fresh waters of Tungurahua-Ecuador are very important because of the diversity of uses they provide and could also be a source and dissemination route of ESBL with a potential risk to public health and the environment. Method: a descriptive, qualitative-quantitative observational study was carried out in the province of Tungurahua. Thirty points (5 rivers, 25 pools) were analyzed by non-probabilistic sampling. Physicochemical variables (pH, chlorine, temperature) were measured in situ and in the laboratory. Bacteria were isolated and phenotypically characterized. A qualitative regulatory analysis was performed to detect regulatory gaps in antimicrobial resistance and ESBL. Results: ESBL phenotype was detected in 28 of the 30 sites (93,3 %): 5 rivers and 23 of the 25 pools. In rivers, E. coli ESBL (72,7 %) and KEC (Klebsiella, Enterobacter, Citrobacter) (27,3 %) were the most frequent. In swimming pools, Acinetobacter ESBL (60,6 %), KEC (15,2 %), Pseudomonas (15,2 %) and E. coli (9,1 %) were the most frequent. Regulatory analysis revealed that TULSMA lacked specific AMR/ESBL parameters, mandatory periodic monitoring and alert thresholds. Conclusions: the evidence revealed severe contamination by ESBL, linked to wastewater and agricultural discharges, which increases the health and environmental risk. There is an urgent need to improve water treatment, discharge controls and monitoring. The TULSMA lacks parameters for AMR, ESBL, ARGs and “One Health” approach; it requires PCR and intersectoral surveillance and active training.