Seawater is a reservoir of multi-resistant Escherichia coli, including strains hosting plasmid-mediated quinolones resistance and extended-spectrum beta-lactamases genes

Abstract

The aim of this study was to examine antibiotic resistance (AR) dissemination in coastal water, considering the contribution of different sources of fecal contamination. Samples were collected in Berlenga, an uninhabited island classified as Natural Reserve and visited by tourists for aquatic recreational activities. To achieve our aim, AR in Escherichia coli isolates from coastal water was compared to AR in isolates from two sources of fecal contamination: human-derived sewage and seagull feces. Isolation of E. coli was done on Chromocult agar. Based on genetic typing 414 strains were established. Distribution of E. coli phylogenetic groups was similar among isolates of all sources. Resistances to streptomycin, tetracycline, cephalothin, and amoxicillin were the most frequent. Higher rates of AR were found among seawater and feces isolates, except for last-line antibiotics used in human medicine. Multi-resistance rates in isolates from sewage and seagull feces (29 and 32%) were lower than in isolates from seawater (39%). Seawater AR profiles were similar to those from seagull feces and differed significantly from sewage AR profiles. Nucleotide sequences matching resistance genes blaTEM, sul1, sul2, tet(A), and tet(B), were present in isolates of all sources. Genes conferring resistance to 3rd generation cephalosporins were detected in seawater (blaCTX-M-1 and blaSHV-12) and seagull feces (blaCMY-2). Plasmid-mediated determinants of resistance to quinolones were found: qnrS1 in all sources and qnrB19 in seawater and seagull feces. Our results show that seawater is a relevant reservoir of AR and that seagulls are an efficient vehicle to spread human-associated bacteria and resistance genes. The E. coli resistome recaptured from Berlenga coastal water was mainly modulated by seagulls-derived fecal pollution. The repertoire of resistance genes covers antibiotics critically important for humans, a potential risk for human health.

Characteristics of ciprofloxacin-resistant Enterobacteriaceae isolates recovered from wastewater of an Algerian hospital

“…PMQR genes detected in this study are among the most frequently described in clinical, animal, food, and environmental Enterobacteriaceae [13,[27][28][29]. Although our strains were resistant to quinolones, the prevalence of PMQR genes was relatively low, consistent with the fact that the contribution of these genes in the level of quinolone resistance is negligible.…”

Studies on avian pathogenic Escherichia coli in commercial broiler chicken in South East Queensland

“…Alternatively, the detection of FQ and ESC resistant bacteria without selection pressure could imply that the bacteria have been introduced into the shed from outside (Alves et al, 2014;Kmeť et al, 2013;Smith et al, 2014). The finding of host restricted sequence types (ST2705 and ST6053) in this study, which have been previously isolated from poultry and wild birds (Dahms et al, 2015;Day et al, 2016;Jones-Dias et al, 2015) supports this hypothesis.…”

“…The majority of these sequence types have been previously described and are globally distributed amongst humans as well as animals (Fernandes et al, 2016;Kim et al, 2011;Maluta et al, 2014;Sola-Gines et al, 2015). This may suggest that the resistant isolates originated from humans (Meyer et al, 2010), wild birds and/or from the farm environment such as water sources (Alves et al, 2014;Sjolund et al, 2008) and then gained access to the poultry production environment.…”

“…Identification of resistance in the absence of antimicrobial selection may indicate that these resistant isolates originated from humans (Meyer et al, 2010), wild birds and/or from the environment (Alves et al, 2014;Sjolund et al, 2008) and gained access to the poultry production environment. Further screening and characterisation of antimicrobial resistant E. coli isolates from wild bird species, wild animals and the environment as occurred in some studies already (Guenther et al, 2011;Radhouani et al, 2014) could provide evidence of a potential risk pathway for the transmission of bacteria as well as the resistance genes.…”

Resistance genes to sulphonamide in commensal Escherichia coli isolated from stool of patients in Mansoura University Children Hospital

“…Actually, a great prevalence of decreased response to antibiotics is usually recorded in screening assays of different bacterial strains (Shears, 2001), and in researches that examined normal bacterial flora as an important index for distribution of genes that are responsible for decreased response to antibiotics (Alves et al, 2014). In addition, developing localities usually suffer from the bad impact of antibiotic resistance on disease outcome and rates of mortality which is due to recurrent infections by bacteria and the great value of antibiotics in fighting them (Adefisoye and Okoh, 2016).…”