Distribution and Genotyping of Aquatic Acinetobacter baumannii Strains Isolated from the Puzi River and Its Tributaries Near Areas of Livestock Farming

Abstract

Acinetobacter baumannii is an important health care-associated bacterium and a common multidrug-resistant pathogen. The use of antibiotics in the husbandry industry has raised concerns about drug-resistant A. baumannii strains, which may affect humans. This study aimed to investigate the seasonal distribution of A. baumannii in aquatic environments near areas of livestock farming. The geographic distribution, antibiotic resistance characteristic, and DNA fingerprinting genotype of A. baumannii were also studied. The results showed that environmental A. baumannii was prevalent during the summer and autumn. The hotspots for A. baumannii were found at the sampling sites of livestock wastewater channels (21.4%; 3/14) and the tributaries adjacent to livestock farms (15.4%; 2/13). The prevalence of A. baumannii at these locations was significantly higher than those adjacent to the Puzi River. Multidrug-resistant strain of A. baumannii was not found in this study, with only one strain (5%; 1/20) being resistant to tetracycline. Of the isolates that were obtained, 10% (2/20) and 20% (4/20) were found to be intermediately resistant to tetracycline and sulphamethoxazole/trimethoprim, respectively. The genotyping patterns and clustering analysis indicated that enterobacterial repetitive intergenic consensus sequence polymerase chain reaction (ERIC-PCR) differentiated A. baumannii strains effectively. There were two major clusters that could then be subtyped into 20 A. baumannii strains with 15 profiles. The A. baumannii strains that were isolated from upstream of the Puzi River and livestock wastewater channels were composed of Cluster I. Cluster II only contained isolates from downstream of the Puzi River area. Furthermore, isolates from adjacent sites were shown to have identical profiles (100%). These results suggest that A. baumannii may have spread through free-flowing water in this study. Therefore, we propose that livestock wastewater is one of the sources that contribute to A. baumannii pollution in water bodies. In summary, continuous monitoring of antibiotic pollution in livestock wastewater is required.

Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus in long-term care facilities in eastern Taiwan

“…The evidence implied that the AB bacteria isolated from LTCFs was not transferred from medical institutions by patients and may come from an outdoor environment. This study is consistent with our previous surveillance in an aquatic environment and is not consistent with other studies conducted in hospitals [575859], which imply the AB isolates in this study may have come from contamination from a local aquatic environment. The MRSA isolates have the same features as hospital-acquired MRSA in antimicrobial susceptibility tests, such as resistance to ciprofloxacin and gentamicin; and in SCCmec typing [5660], hospital-acquired MRSA-6 was isolated from nasogastric tubes, suggesting an association of drug-resistant strains in LTCF residents with frequent contact with nosocomial strains from hospitals.…”

Insight into the hidden bacterial diversity of Lake Balaton, Hungary

“…and Pseudomonas aeruginosa according to Lavenir et al (2007), Legionella spp. according to Cloud et al (2000), Legionella pneumophila according to Fiume et al (2005), Acinetobacter baumannii according to Tsai et al (2018) and Stenotrophomonas maltophilia according to Filho et al (2004).…”

Monitoring Antimicrobial Resistance Dissemination in Aquatic Systems

“…Further testing of 20 A. baumannii isolates against 7 antibiotics (ciprofloxacin, cefepime, gentamicin, imipenem, ampicillin-sulbactam, sulfamethoxazole/trimethoprim, tetracycline) by the Kirby-Bauer disk diffusion test showed that only 10% had resistance to sulfamethoxazole/trimethoprim and 5% had resistance to tetracycline. Although the A. baumannii isolated by Tsai et al [32] did not display MDR patterns which are regarded a serious AMR threat by WHO, their epidemiological potential warrants further studies on prevalence and AMR developmental trends in the environment.…”

“…This special issue comprises of 11 research articles that fall within the scope of AMR. Broadly, topics extend from AMR monitoring and surveillance in environmental resources and effluents from water/wastewater treatment plants [32][33][34][35][36][37][38][39], antimicrobial ecological risk assessments of two river reservoir systems in China that are sources of drinking water supply [40,41], and exploring novel strategies of using engineered antimicrobial peptides (AMP) to target specific bacteria to disrupt biofilms that are major causes of chronic and persistent infections [42].…”

“…The use of antimicrobials in food animals is widespread, and runoffs originating from animal waste may carry unmetabolized antibiotics or ARB and ARGs that have direct impact on surrounding water bodies [46]. Tsai et al [32] linked significantly higher concentrations of A. baumannii along the Puzi River in China to sampling sites of livestock wastewater channels and tributaries adjacent to livestock farms. Further testing of 20 A. baumannii isolates against 7 antibiotics (ciprofloxacin, cefepime, gentamicin, imipenem, ampicillin-sulbactam, sulfamethoxazole/trimethoprim, tetracycline) by the Kirby-Bauer disk diffusion test showed that only 10% had resistance to sulfamethoxazole/trimethoprim and 5% had resistance to tetracycline.…”