Pathogenic Escherichia coli Strains Recovered from Selected Aquatic Resources in the Eastern Cape, South Africa, and Its Significance to Public Health

Abstract

The prevalence of pathogenic microorganisms, as well as the proliferation of antimicrobial resistance, pose a significant threat to public health. However, the magnitude of the impact of aquatic environs concerning the advent and propagation of resistance genes remains vague. Escherichia coli (E. coli) are widespread and encompass a variety of strains, ranging from non-pathogenic to highly pathogenic. This study reports on the incidence and antibiotic susceptibility profiles of E. coli isolates recovered from the Nahoon beach and its canal waters in South Africa. A total of 73 out of 107 (68.2%) Polymerase chain reaction confirmed E. coli isolates were found to be affirmative for at least one virulence factor. These comprised of enteropathogenic E. coli 11 (10.3%), enteroinvasive E. coli 14 (13.1%), and neonatal meningitis E. coli 48 (44.9%). The phenotypic antibiogram profiles of the confirmed isolates revealed that all 73 (100%) were resistant to ampicillin, whereas 67 (91.8%) of the pathotypes were resistant to amikacin, gentamicin, and ceftazidime. About 61 (83.6%) and 51 (69.9%) were resistant to tetracycline and ciprofloxacin, respectively, and about 21.9% (16) demonstrated multiple instances of antibiotic resistance, with 100% exhibiting resistance to eight antibiotics. The conclusion from our findings is that the Nahoon beach and its canal waters are reservoirs of potentially virulent and antibiotic-resistant E. coli strains, which thus constitute a potent public health risk.

Determination of the Microbial and Chemical Loads in Rivers from the Quito Capital Province of Ecuador (Pichincha)—A Preliminary Analysis of Microbial and Chemical Quality of the Main Rivers

“…When compared to the present study, other countries, such as Australia, South Africa, and Nigeria, reported the presence of four E. coli pathotypes [ 70 , 71 , 72 ]. This diversity in pathotypes could be due to several sanitation issues and zoonotic transmission by wild and livestock animals [ 73 , 74 , 75 ]. Ramírez Castillo and colleagues [ 8 ] identified EAEC as the most prevalent E. coli pathotype in the water set of San Pedro River (Aguascalientes State, Mexico), in contrast to our results.…”

Detection of Carbapenem-Resistance Genes in Klebsiella Species Recovered from Selected Environmental Niches in the Eastern Cape Province, South Africa

“…Bacterial DNA was extracted by performing the boiling method as described by Jackson et al [ 22 ]. Briefly, 4 mL of NB was prepared and presumptive isolates were resuscitated and also extracted from the broth cultures following the method as described in a previous study [ 23 ]. The DNA templates were stored at −20 °C for further molecular analyses.…”

Genetic Characterization Among Carbapenem-resistant Escherichia coli Strains Using Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) Fingerprinting in South Africa

“…The positive control (ATCC 25922) was used. The positively con rmed E. coli isolates were further screened for the presence of virulence genes representing the various pathotypes using the primer sets reported by Ebomah et al [6] as shown in Table S1. Veri cation of the PCR ampli ed products was determined by resolving them in 1.5% agarose gel at 135 volts for 30 min, identi ed under a short-wavelength UV light source (Alliance 4.7).…”

“…The pathogenicity is determined by strains that harbor virulence genes (VGs), and among which are the main causative agents of diarrhea such as Enteropathogenic E. coli (EPEC), Enteroaggregative E. coli (EAEC) and Enterotoxigenic E. coli (ETEC) which harbor VGs comprising bfp (bundle-forming pili), AafI (aggregative adherence mbrae I) and lt (heat-labile enterotoxin) respectively [4,5]. Other relevant E. coli pathotypes and VGs they harbor include the following: diffusely adherent E. coli, DAEC (VG: daae); neonatal meningitis-causing E. coli, NMEC (VG: ibeA); enterohaemorrhagic E. coli, EHEC (VG: stx/eae); shiga toxin-producing E. coli, STEC (VG: stx1/stx2) [6]. For many years, beta-lactam class of antibiotics remained the key therapeutic option for stern infections, and carbapenems are often considered antimicrobials of last choice [7].…”