Multiresistant waterborne pathogens isolated from water reservoirs and cooling systems

Abstract

Aims: To determine the incidence of multiple antibiotic‐resistant strains of the emergent human pathogens Legionella pneumophila, Pseudomonas aeruginosa and mesophilic Aeromonas species among those isolated from water reservoirs and industrial cooling systems. Methods and Results: Water from four natural water reservoirs and four industrial cooling towers was sampled for 1 year period. The total heterotrophs, mesophilic Aeromonas, Pseudomonas spp. and Legionella spp. counts were performed as recommended by standard procedures, and the sensitivity of the isolates to 27 antibiotics was tested. A total of 117 Aeromonas, 60 P. aeruginosa and 15 L. pneumophila strains were isolated and identified by means of biochemical tests and DNA probes. 46·4% of Aeromonas, and 100% of P. aeruginosa isolates presented multiple resistance. Legionella pneumophila strains were generally sensitive to the drugs used. Conclusions: Antibiotic‐resistant pathogenic bacteria belonging to P. aeruginosa and mesophilic Aeromonas species are common in natural aquatic environments. Thus, the risk of waterborne diseases owing to domestic and industrial uses of freshwater should be re‐examined from the increase of bacterial resistance point of view. Significance and Impact of the Study: These data confirm the emergence of bacteria resistant to antibiotics in aquatic environments.

Dynamics of Aeromonas species isolated from wastewater treatment system

“…The absence of correlation can be explained by differences in characteristics of each group of organisms, such as occurrence of enteric organisms, in the case of E. coli. On the other hand, the genus Aeromonas can get into the stabilization pond system through the faecal pathway, even though they are primarily ubiquitous in the aquatic environment, where they can multiply or tolerate changes in dynamics, association to and/or competition with bacterial flora, and other environmental variations (Hassani et al 1992;Benchokroun et al 2003;Maalej et al 2003;Sautour et al 2003;Blasco et al 2008). In the present study, most of the known species of…”

<i>Aeromonas hydrophila</i> subsp. <i>dhakensis</i> Isolated from Feces, Water and Fish in Mediterranean Spain

“…Most clinical microbiology laboratories still routinely rely on easy-to-use phenotypic methods (39); therefore, key traits for discriminating at least those Aeromonas species relevant in clinical sources should be well defined (25, 39). In a previous study, 215 Aeromonas isolates were recovered from river water and cooling systems (8), from wild European eels (13), and from human feces, collected during a 1-year period at locations in the river Xúquer floodplain, a highly urbanized and industrialized metropolitan area (753,552 inhabitants) around the city of Valencia (800,469 inhabitants). Eight out of these 215 aeromonads were presumptively identified as A. hydrophila , despite their negative production of acid from l -arabinose.…”

Is domestic tap water a risk for infections in neutropenic patients?

“…Thus, it could be postulated that about half of the patients seem to acquire P. aeruginosa outside the hospital, and contaminated tap water must be considered as one of the likely sources. Contamination of tap water with P. aeruginosa has been described in several reports [3,21].…”