Evaluación de la resistencia bacteriana aislada de aguas destinadas al abastecimiento público de la parroquia Punín

Abstract

The study conducted for the evaluation of bacterial resistance isolated in waters intended for public supply in Punín town focused on performing chemical, physical, and microbiological analyses at various water distribution points in the area. The parameters evaluated included color, turbidity, odor, temperature, pH, conductivity, total solids, residual chlorine, nitrates, nitrites, lead, and fecal coliforms according to the NTE INEN 1 108:2020 standard, using spectrophotometric and microbiological methods. Additionally, other bacteria present at each analyzed point were isolated, followed by the study of bacterial resistance for each isolated microorganism. The analyses revealed non-compliance with parameters such as color, averaging 12.52 (Pt-Co), lead, averaging 0.07 mg/L, and fecal coliforms, averaging 9.85 MPN/100 ml. Among the isolated bacteria, microorganisms such as Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Staphylococcus aureus, and Staphylococcus epidermidis were identified, with Staphylococcus epidermidis being the most prevalent, present at all studied points. In conclusion, the antibiogram study conducted according to the Clinical and Laboratory Standards Institute (CLSI) guidelines revealed the presence of extended-spectrum beta-lactamase (ESBL) enzymes in Escherichia coli, Klebsiella oxytoca, and Klebsiella pneumoniae. Furthermore, resistance in Staphylococcus aureus and Staphylococcus epidermidis to penicillinase group drugs, such as oxacillin and penicillin, was identified, with more pronounced resistance to oxacillin. Staphylococcus aureus also showed resistance to azithromycin