Antimicrobial Resistance in the Environment

Abstract

This review summarizes selected publications of 2016 with emphasis on occurrence and treatment of antibiotic resistance genes and bacteria in the aquatic environment and wastewater and drinking water treatment plants. The review is conducted with emphasis on fate, modeling, risk assessment and data analysis methodologies for characterizing abundance. After providing a brief introduction, the review is divided into the following four sections: i) Occurrence of AMR in the Environment, ii) Treatment Technologies for AMR, iii) Modeling of Fate, Risk, and Environmental Impact of AMR, and iv) ARG Databases and Pipelines.

Strategic Approach for Prioritising Local and Regional Sanitation Interventions for Reducing Global Antibiotic Resistance

“…Data on the concentrations and removal rates of ARB and ARGs in different waste processing and wastewater treatment processes are varied, depending on the mitigation step, and also the format, type and measurement methods used (see [42][43][44][45][46][47][48][49][50]). For example, limited ARG and ARB reduction data exist on the most basic mitigation options, such as the value of moving from OD to improved basic sanitation.…”

“…The ARGs used for comparisons here were chosen because they are measured in most treatment studies by a common analytical method, quantitative Polymerase Chain Reaction. For our study, we chose specific ARG data from nine manuscripts that examined full-or field-scale systems [42][43][44][45][46][47][48][49][50]. Other manuscripts were considered, but our goal was to contrast ARG conditions and removal rates only in "real" sanitation systems.…”

“…Using Figure 1 as a guide, Figures 2 and 3 were developed based on literature data to compare the relative AR mitigation value and costs of the four main sanitation steps. Figure 2 was developed based on ARG reduction data drawn from nine studies [42][43][44][45][46][47][48][49][50]. In summary, roughly log 4 to 6 ARG reductions occur from OD to improved basic sanitation (although this is hugely variable); improved basic sanitation to primary treatment adds a further 0.0 to 1.0 log reduction in ARGs; primary to secondary treatment provides an additional log 1.0 to 2.0 reduction; and finally, secondary to tertiary treatment adds a further log 1.0 to 3.0.…”

“…Reductions are baselined to an initial ARG concentration of (log 10) ARG copies/unit volume in the faecal matter, which is the brown bar. Each step reduction is based on mean ARG removal data from nine studies on the field-scale systems [42][43][44][45][46][47][48][49][50]. Sample numbers: n = 5 for faecal matter to improved sanitation; n = 8 for improved sanitation to primary treatment; n = 11 for primary to secondary treatment; n = 15 for secondary to tertiary treatment.…”

Antibiotic Resistance Genes in Freshwater Trout Farms in a Watershed in Chile

“…The effluent from fish farms may contain antibiotic residues, antibiotic resistant bacteria (ARB), and antibiotic resistance genes (ARGs). Once in the aquatic environment, gene exchange can occur between bacteria, including environmental bacteria, and ARGs can then be further disseminated through the natural environment (Baquero et al, 2008, Bengtsson‐Palme et al, 2017; Waseem et al, 2017). There is a lack of quantitative studies attributing environmental ARG abundance to specific sources such as fish farms (Williams‐Nguyen et al, 2016; Bueno et al, 2017).…”