Occurrence of Antibiotic Resistance Genes, Antibiotics-Resistant and Multi-Resistant Bacteria and Their Correlations in One River in Central-Western Brazil

Abstract

(1) Background: The uncontrolled increase in pollutants in the aquatic environment results in antibiotic-resistant bacteria and antibiotic resistance genes (ARBs and ARGs). The overuse and misuse of antibiotics is also a crucial factor for public health. (2) Methods: In this study, the presence of ARBs and the presence of 24 resistance genes from eight different classes of antibiotics were evaluated in addition to performing statistical correlations and intercorrelations. Samples of water and sediment were collected from a river in central-western Brazil, responsible for supplying water to more than 3 million people. Physicochemical analyses were performed on the water samples, as well as methodological approaches based on culture and molecular biology, such as real-time polymerase chain reaction (qPCR). (3) Results: The results of the analysis of apparent color, turbidity, thermotolerant coliforms and E. coli were not in accordance with Brazilian legislation. A total of 203 bacterial strains were isolated, of which 30.54% were from the Entero-bacteriaceae family and 29.06% from the Staphylococcaceae family. For the ARBs found, a higher prevalence of resistance to lyconsamides and β-lactams was detected. Among all isolated strains, a multi-drug resistance profile of 59.37% was found. The presence of ARGs was detected in all water and sediment samples; of the 24 genes searched, the presence of 22 was found, and the sul2 and ermC genes were detected in all samples. According to the statistical analysis, the Meia Ponte River is suffering a great anthropogenic impact, and the current Brazilian legislation is not sufficient to prevent it. This water environment is serving as a reservoir of resistance genes, and measures such as monitoring, depollution, management and preservation must be taken, so that the population does not suffer great damage. (4) Conclusions: This is the first study in the State of Goiás, Brazil, to indicate the existence of ARGs in samples of raw water and river sediments, supporting the worldwide investigation of ARBs and ARGs in a water environment. In addition, few studies address the correlations between the ARBs and ARGs groups, which is an important factor in the field of antimicrobial resistance.