Antibiotic resistant bacteria in Windermere and two remote upland tarns in the English Lake District

Abstract

The incidence of antibiotic resistance was determined in over 2000 bacteria which were divided into the following groups: faecal streptococci, coliforms (excluding Escherichia coli), E. coli, Pseudomonas spp. and aquatic bacteria (i.e. bacteria predominant in the lake water which were excluded from the previous four categories). The isolates were obtained from the water of Windermere (English Lake District) and from a sewage effluent which entered the lake. With the exception of the faecal streptococci, the incidence of antibiotic resistance was higher in the bacteria isolated from the lake water than in those from the effluent, and ranked according to groups Pseudomonas spp. greater than E. coli greater than aquatic bacteria greater than coliforms greater than faecal streptococci. The highest incidence of multiple resistance was found among the pseudomonads. When corrected for the relative size of each population the pool of antibiotic resistance in the aquatic bacteria was by far the largest. The incidence of antibiotic resistance in aquatic bacteria isolated from Windermere was, however, lower than in those isolated from two remote upland tarns. This finding may have been due to differences in the species composition of the three sites except that the same results were obtained when only fluorescent pseudomonads were tested. The upland tarns were not totally isolated from man and other animals but did not receive any sewage or other effluents and therefore the results were surprising. Possible explanations include a lack of susceptibility in aquatic bacteria and increased resistance associated with growth in nutrient poor environments.

Impact of an Urban Effluent on Antibiotic Resistance of Riverine Enterobacteriaceae and Aeromonas spp

“…For example, both ampicillin and cephalothin are inactivated by chromosomal beta-lactamases produced by many enterobacterial (17) and Aeromonas (40) species. Most studies on bacterial antibiotic resistances in sewage (3,18), freshwater (3,9,27,33,34), and seawater (8,38) did not take into account these elements, leading to unexpected conclusions. For example, Jones et al (27) found a higher incidence of resistance in the bacteria isolated from remote upland tarns than in those isolated from a polluted lake or a sewage, with the highest values being observed for pseudomonads, which are naturally multiresistant organisms.…”

“…Urban effluents are known to contain high levels of antibiotics and antibiotic-resistant bacteria belonging to the human and animal commensal flora, mainly Enterobacteriaceae (9,22,27). In order to study the impact of an urban effluent on the antimicrobial resistance of the microbial riverine flora, the acquired antibiotic resistance rates of enterobacteria and Aeromonas spp.…”

“…However, in many freshwater systems, fecal bacteria are of little numerical significance despite the fact that they are discharged into almost all inland waters (27). Thus, if the environmental pool of resistance is to be measured, bacteria other than those of fecal origin must be considered.…”

Occurrence of multiple antibiotic resistance and R-plasmids in gram-negative bacteria isolated from faecally contaminated fresh-water streams in Hong Kong

“…In the present study, Jones and his colleagues (1986b) have also emphasized that the methods and media used in detecting antibiotic-resistant bacteria affect the results. The level of antibiotic resistance in the environment is also affected by the location of the samples taken and the species of bacteria isolated (Jones et al 1986a, b). In the present study, differences in the overall proportions of antimicrobial resistance at the sampling sites may be partly explained by differences in the proportions of different bacterial species isolated (Table 4).…”

Use of Microbes From Seabird Faeces to Evaluate Heavy Metal Contamination in Antarctic Region

“…However, the tolerance to heavy metal toxicity can also be influenced by several environmental factors like constituents of ecosystem, ion interactions, pH, the form and availability of metals to the microbes. Thus, bacterial tolerance to metal toxicity is a significant environmental phenomenon (Sterritt and Lester, 1980;Jones et al, 1986).…”