The prevalence of bacteria with multidrug-resistance (MDR) is a significant threat to public health globally. Listeria spp. are naturally ubiquitous, with L. monocytogenes particularly being ranked as important foodborne disease-causing microorganisms. This study aimed to evaluate the incidence and determine the antimicrobial resistance (AMR) profiles of multidrug-resistant Listeria spp. (MDRL) isolated from different environmental samples (river and irrigation water) in the Sarah Baartman District Municipality (SBDM), Eastern Cape Province (ECP), South Africa. Molecular identification and characterization were carried out using polymerase chain reaction (PCR) and isolates that exhibited phenotypic resistance were further screened for relevant antimicrobial-resistant genes (ARGs). Findings revealed a total of 124 presumptive Listeria isolates; 69 were molecularly confirmed Listeria species. Out of the confirmed species, 41 isolates (59%) were classified as L. monocytogenes while 9 (13%) were classified as L. welshimeri. All Listeria spp. exhibited phenotypic resistance against ampicillin, penicillin, and trimethoprim-sulphamethoxazole and further screening revealed ARGs in the following proportions: sulI (71%), blaTEM (66%), tetA (63%), and blaCIT (33%). Results confirmed the occurrence of ARGs among Listeria inhabiting surface waters of ECP. The present study indicates that the river water samples collected from SBDM are highly contaminated with MDRL, hence, constituting a potential health risk.

Carbapenemase-producing Enterobacteriaceae (CPE) have been heavily linked to hospital acquired infections (HAI) thereby leading to futility of antibiotics in treating infections and this have complicated public health problems. There is little knowledge about carbapenemase-producing Klebsiella spp. (CPK) in South Africa. This study aimed at determining the occurrence of CPK in different samples collected from selected environmental niches (hospitals, wastewater treatment plants, rivers, farms) in three district municipalities located in the Eastern Cape Province, South Africa. Molecular identification and characterization of the presumptive isolates were determined using polymerase chain reaction (PCR) and isolates that exhibited phenotypic carbapenem resistance were further screened for the possibility of harbouring antimicrobial resistance genes. One hundred (43%) of the 234 confirmed Klebsiella spp. isolates harboured carbapenem-resistance genes; 10 isolates harboured blaOXA-48-like; 17 harboured blaKPC; and 73 isolates harboured blaNDM-1. The emergence of blaKPC, blaOXA-48-like, and blaNDM-1 carbapenem-resistance genes in Klebsiella species associated with environmental sources is of great concern to public health.

This article provides an overview of the antibiotic era and discovery of earliest antibiotics until the present day state of affairs, coupled with the emergence of carbapenem-resistant bacteria. The ways of response to challenges of antibiotic resistance (AR) such as the development of novel strategies in the search of new antibiotics, designing more effective preventive measures as well as the ecology of AR have been discussed. The applications of plant extract and chemical compounds like nanomaterials which are based on recent developments in the field of antimicrobials, antimicrobial resistance (AMR), and chemotherapy were briefly discussed. The agencies responsible for environmental protection have a role to play in dealing with the climate crisis which poses an existential threat to the planet, and contributes to ecological support towards pathogenic microorganisms. The environment serves as a reservoir and also a vehicle for transmission of antimicrobial resistance genes hence, as dominant inhabitants we have to gain a competitive advantage in the battle against AMR.

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.

Pathogenic bacterial strains that cause serious infections particularly among individuals with immune-deficiency can exhibit antibiotic-resistance against the available therapeutic options thereby constituting a public health concern. In this study, we evaluated the occurrence of carbapenem-resistant Enterobacter species isolated from different environmental samples collected from selected study areas in the Eastern Cape Province, South Africa. Our study further aimed to evaluate the antimicrobial-resistant (AMR) profiles of the confirmed isolates recovered from hospital wastewater effluents, wastewater treatment plants and other environmental sources including river water and farm samples. Results revealed out of 142 PCR-confirmed Enterobacter spp., 115 isolates (81%) were classified as Enterobacter cloacae. The confirmed species exhibited phenotypic resistance in decreasing order for doripenem (80%), meropenem (75%), imipenem (72%) and ertapenem (66%) and carbapenem-resistance genes (CRGs) were detected in 29% of Enterobacter spp. isolates. Our findings confirm the presence of CRGs among bacterial isolates populating environmental niches.

Contamination of water resources by pathogens due to ever increasing anthropogenic activities and the related disease burden remains a major concern of water quality globally. This study evaluated the physicochemical and microbiological quality indices of Nahoon Beach and its canal waters in South Africa over a period of 12 months (September 2014 to August 2015). Water samples were collected biweekly from 6 sampling points (3 on the beach and 3 on the canal) and analyzed using standard methods. The physicochemical qualities of the beach and canal waters ranged as follows: turbidity 3.3-99.9 NTU, temperature 15-25ºC, pH 7-10, electrical conductivity 30.0-741.7 µS/cm, and total dissolved solids 19-546 mg/l. As for microbial counts of the water samples, Escherichia coli counts ranged in the order of 10 1-10 3 CFU/100 ml while Enterococcus counts varied in the order of 10 1-10 2 CFU/100 ml. This study underscores the need for the protection of recreational water resources to safeguard public health.

Acinetobacter species have been found in a variety of environments, including soil, food, plants, hospital environments and water. Acinetobacter baumannii is an opportunistic and emerging waterborne pathogen. It has been implicated in several nosocomial infections that demonstrate resistance to commonly administered antibiotics. We investigated phenotypic antibiotic resistance (PAR) and relevant antibiotic resistance genes (ARGs) in A. baumannii isolated from three freshwater resources in the Eastern Cape Province, South Africa; A. baumannii (410) was confirmed by the recA and gyrB genes of 844 suspected Acinetobacter species in the water samples. The PAR of the confirmed isolates was assessed using a panel of 11 antibiotics by the disc diffusion method, while ARGs were investigated in isolates exhibiting PAR. The A. baumannii isolates were resistant to piperacillin-tazobactam (11.2%), ceftazidime (12%), cefotaxime (18.8%), cefepime (8.8%), imipenem (2.7%), meropenem (4.15%), amikacin (2.4%), gentamicin (8.8%), tetracycline (16.8%), ciprofloxacin (11%) and trimethoprim/sulfamethoxazole (20.5%). For multidrug resistance (MDR), two isolates were resistant to all antibiotics and 28 isolates were resistant to imipenem and meropenem. Moreover, β-lactamases blaTEM (64.4%) and blaOXA-51 (28.70%) as well as sulphonamides sul1 (37.1%) and sul2 (49.4%) were common ARGs. Overall, PAR and ARGs had positive correlations (r) in all rivers. Detection of MDR-A. baumannii in freshwater resources could be linked to possible wastewater discharge from the nearby animal farms, indicating potential implications for public health.

Background Carbapenems belong to beta-lactam class of antibiotics usually considered as the last line of defense because they can be effective against severe infections caused by prevalent multidrug-resistant (MDR) pathogens. However, carbapenems can be deactivated by bacteria that produce carbapenemase (beta-lactamase). This study was conducted to screen for carbapenem-resistance genes (CRGs) harbored by pathogenic strains of Escherichia coli recovered from different environmental samples. We also assessed the genetic relatedness among selected E. coli pathotypes using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR).Method: Molecular identification and characterization of the presumptive isolates were performed using PCR and isolates that exhibited antimicrobial resistance (AMR) phenotypically were further screened for some relevant CRGs (blaNDM−1, blaKPC and blaOXA−48−like). Furthermore, ERIC-PCR was used to determine the similarity and diversity of 31 E. coli strains which were randomly selected from the different sources analyzed in this study.Result Our findings revealed a total of 238 presumptive E. coli isolates, out of which 192 were confirmed positive for uidA gene. Further screening revealed 77 (40%) isolates belong to six key E. coli pathotypes and 70 of them exhibited phenotypic AMR. Additionally, twenty-nine (41%) of the 70 MDR pathogenic E. coli strains harbored CRGs; with 24 strains harboring blaNDM−1, 8 harboring blaKPC and 2 harboring blaOXA−48−like genes.Conclusion Findings also suggest that the selected E. coli pathotypes belonged to different genomic clusters, while the cluster analysis showed a possible genetic diversity among aquatic and farm isolates. Proper treatment of final effluents before discharge as well as the development of more effective strategies to control and manage the use of antimicrobial agents were strongly recommended.