Rainfall increases the abundance of antibiotic resistance genes within a riverine microbial community. (July 2017)

• Record Type: Journal Article
• Authors: Di Cesare, Andrea; Eckert, Ester M.; Rogora, Michela; Corno, Gianluca
• Is Part Of: Environmental pollution. Volume 226(2017)
• Page Start: 473
• Page End: 478
• Publication Date: 2017-07
• Subjects: Antibiotic resistance -- River pollution -- River microbial community -- Rain -- Anthropic impact; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2017.04.036
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Infections with antibiotic resistant bacteria are among the major threats for human health. Studies elucidating the role of the environment in their spread are still in their infancy, it, however, seems that different environments might function as a long-term reservoir of antibiotic resistance genes (ARGs) that reside within their microbial communities. An increasing number of studies target the presence and the persistence of ARGs in waters and soils that are exposed to human activities; they, however, rarely consider the spatial/temporal variability that predominate in these environments. Here we evaluated the effect of a moderate rain event (4 mm rain h −1 ) on the abundance and distribution of ARGs ( tet A, erm B, bla CTXM, sul II, and qnr S), by comparing measurements of gene abundances during the rainfall to the yearly average, in the waters of a large subalpine river. ARG abundances, which all increased during the rain event, were then correlated to several microbiological, physical and chemical variables, in order to establish their potential origin. Increments in ARG abundances during rainfall (total ARGs: 24 fold) was concomitant to an increase in total phosphorous, N-NH4, and microbial aggregates. Our results show a strong influence of a moderate rainfall on the abundances of ARGs, and suggest the catchment as their source. The impact of moderate rainfalls in areas exposed to anthropic activities should then be considered in modelling and management of ARG dynamics. Graphical abstract: Highlights: The abundances of antibiotic resistance genes in a river increase during a rain event. Antibiotic resistance genes during the rain event are higher than the yearly average. Chemical parameters indicate that the input derives from the surrounding soils. Monitoring of antibiotic resistance genes should consider rain events. Abstract : Moderate rainfalls influence the abundance of antibiotic resistance genes (ARGs) in rivers, imposing the consideration of these events while monitoring ARGs in aquatic environments.