• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.414-422
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• 2001

Antibiotic resistance in human pathogens is a major public health issue. Some of the resistance problem can be attributed to the transfer of resistant bacteria from animals to people and the transfer of resistance genes from animal pathogens and commensal bacteria to human pathogens. Control measures include improvements in food hygiene to reduce the spread of zoonotic bacteria to people via the food chain. However, to specifically address the issue, the medical profession must control misuse and overuse of antibiotics in hospitals and community practice. In addition, the livestock industries and their advisors must reduce and refine the use of antibiotics in animal production and replace antibiotics with alternative disease control measures as much as possible.

• BMB Reports
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• v.56 no.6
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• pp.326-334
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• 2023

Antibiotic resistance (AR) is a silent pandemic that kills millions worldwide. Although the development of new therapeutic agents against antibiotic resistance is in urgent demand, this has presented a great challenge, especially for Gram-negative bacteria that have inherent drug-resistance mediated by impermeable outer membranes and multidrug efflux pumps that actively extrude various drugs from the bacteria. For the last two decades, multidrug efflux pumps, including AcrAB-TolC, the most clinically important efflux pump in Gram-negative bacteria, have drawn great attention as strategic targets for re-sensitizing bacteria to the existing antibiotics. This article aims to provide a concise overview of the AcrAB-TolC operational mechanism, reviewing its architecture and substrate specificity, as well as the recent development of AcrAB-TolC inhibitors.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.335-343
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• 2022

BACKGROUND: Antibiotics used in animal husbandry for disease prevention and treatment have resulted in the rapid progression of antibiotic resistant bacteria which can be introduced into the environment through livestock feces/manure, disseminating antibiotic resistant genes (ARGs). In this study, fecal samples were collected from the livestock farms located in Jeju Island to investigate the relationship between microbial communities and ARGs. METHODS AND RESULTS: Illumina MiSeq sequencing was applied to characterize microbial communities within each fecal sample. Using quantitative PCR (qPCR), ten ARGs encoding tetracycline resistance (tetB, tetM), sulfonamide resistance (sul1, sul2), fluoroquinolone resistance (qnrD, qnrS), fluoroquinolone and aminoglycoside resistance (aac(6')-Ib), beta-lactam resistance (bla_TEM, bla_CTX-M), macrolide resistance (ermC), a class 1 integronsintegrase gene (intI1), and a class 2 integrons-integrase gene (intI2) were quantified. The results showed that Firmicutes and Bacteroidetes were dominant in human, cow, horse, and pig groups, while Firmicutes and Actinobacteria were dominant in chicken group. Among ARGs, tetM was detected with the highest number of copies, followed by sul1 and sul2. Most of the genera belonging to Firmicutes showed positive correlations with ARGs and integron genes. There were 97, 34, 31, 25, and 22 genera in chicken, cow, pig, human, and horse respectively which showed positive correlations with ARGs and integron genes. In network analysis, we identified diversity of microbial communities which correlated with ARGs and integron genes. CONCLUSION(S): In this study, antibiotic resistance patterns in human and livestock fecal samples were identified. The abundance of ARGs and integron genes detected in the samples were associated with the amount of antibiotics commonly used for human and livestocks. We found diverse microbial communities associated with antibiotics resistance genes in different hosts, suggesting that antibiotics resistance can disseminate across environments through various routes. Identifying the routes of ARG dissemination in the environment would be the first step to overcome the challenge of antibiotic resistance in the future.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.851-865
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• 2018

This study investigated the prevalence of Listeria monocytogenes in slaughterhouses, and determined serovars and genotypes, and antibiotic resistance of the isolates obtained from slaughterhouses and humans in Korea. Two hundred ninety samples were collected from feces (n=136), carcasses [n=140 (cattle: n=61, swine: n=79)], and washing water (n=14) in nine slaughterhouses. Eleven human isolates were obtained from hospitals and the Korea Center for Disease Control and Prevention. Listeria monocytogenes was enriched and identified, using polymerase chain reaction (PCR) and 16S rRNA sequencing. Serovars and presence of virulence genes were determined, and genetic correlations among the isolates were evaluated by the restriction digest patterns of AscI. Antibiotic resistance of L. monocytogenes isolates were examined against 12 different antibiotics. Of 290 slaughterhouse samples, 15 (5.17%) carcass samples were L. monocytogenes positive. Most L. monocytogenes isolates possessed all the virulence genes, while polymorphisms in the actA gene were found between carcass and human isolates. Serovars 1/2a (33.3%) and 1/2b (46.7%) were the most frequent in carcass isolates. Genetic correlations among the isolates from carcass and clinical isolates were grouped within serotypes, but there were low geographical correlations. Most L. monocytogenes isolates were antibiotic resistant, and some strains showed resistance to more than four antibiotics. These results indicate that L. monocytogenes are isolated from carcass and human in Korea, and they showed high risk serotypes and antibiotic resistance. Therefore, intensive attentions are necessary to be aware for the risk of L. monocytogenes in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.626-633
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• 2023

Vibrio spp. are aquatic bacteria that are ubiquitous in warm estuarine and marine environments. Especially, V. vulnificus and V. cholerae are currently known to cause potentially fatal infections in humans. This study investigated the distribution and antibiotic resistance of V. vulnificus and V. cholerae isolated from coastal areas of Gyeongsangnam-do in 2022. A total of 252 samples of water, shellfish and coastal sediment were collected from 7 locations along the coast, and 124 samples of fishery products were collected from markets. Among the 252 samples, forty-four V. vulnificus (11.7%) and fourteen V. cholerae non-O1/non-O139 (3.7%), none of which carried the ctx gene, were isolated. Out of the 124 samples, 6 (4.8%) tested positive for V. vulnificus and V. cholerae was not detected. The isolation rates of V. vulnificus and V. cholerae showed a significant correlation with environmental factors such as seawater temperature and salinity. In an antibiotic resistance test, V. vulnificus was susceptible to amikacin, gentamicin, imipenem trimethoprim/sulfamethoxazole, and ciprofloxacin, but resistant to cefoxitin (100.0%), followed by tetracycline (9.1%). Multidrug resistance was also observed. Continuous monitoring of Vibrio pathogens with water temperature and salinity is expected to help reduce the outbreaks, and rational use of antibiotic agents is needed to prevent the accession of antibiotic-resistant microorganisms in aquatic ecosystems.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.742-749
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• 2011

Purpose: This study was conducted to examine public level of knowledge and attitudes regarding antibiotic use and potential drug resistance. Methods: A cross-sectional face-to-face survey of 1,177 residents aged 18 or over was conducted in Korea. A quota sampling method was used. Results: Most respondents (70%) did not know that antibiotics are ineffective in treating coughs and colds. Two-thirds of the respondents were unaware of the conditions under which antibiotic resistance occurs, despite understanding the concept of resistance. Lower education level and older age were independently associated with inadequate knowledge. Lower education level, older age, inadequate knowledge and no exposure to the education campaign were independently associated with poor attitude. Conclusion: The results of this study demonstrate that the general public has misunderstandings and a lack of knowledge with regard to antibiotic use, despite a national educational campaign. However, the campaign may have had an effect on the public's attitudes towards antibiotics.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.119-122
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• 2006

In both untreated and conventionally stabilized swine manures antibiotic resistant (AR) microorganisms, Staphylococcus-like and Salmonella-like microorganisms were detected. Also pathogens with MAR phynotype were detected. Presence of such microorganisms suggest high level of pathogen-related health risk to farmers who may be in direct contact with the manure and its conventionally stabilized product In contrast the autothermal thermophilic aerobic digestion (ATAD) treatment have efficiently reduced AR and pathogenicity from the swine manure. When soil was fertilized using swine manure and its stabilized products, despite no detection of MAR-exhibiting pathogen-like microorganisms in fertilized soil, potential pathogen-related health risk could not be ruled out from the fertilized soil since the organic fertilization led to increase in AR and pathogenicity in the soil microbial communities. As conclusion, this microbiological study demonstrated that an ATAD process is applicable in control of pathogen-related health risk in livestock manure.

• Journal of Environmental Health Sciences
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• v.15 no.1
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• pp.63-73
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• 1989

The purposes of this study were to find out the heavy metal and antibiotic resistant coliform bacteria from mineral water and the resistant factors. For the experiment, mineral water samples were taken from A area and B area during the period from march to July, 1988. The results of the experiment were as follows 1. From mineral water, eleven resistant coliforms and one susceptible coliform were isolated. 2. All resistant isolates harbored diverse plasmids of ranged ca. 14-54kb. 3. Susceptible coliform harbored a only plasmid of ca. 2.8 kb. 4. All resistant isolates harbored common size of plasmid of ca. 14kb. 5. As a result of the transformation and agarose gel electrophoresis experiments, resistant factor was R-plasmid. In conclusion, It is suggested that heavy metal contamination of mineral water is the selective pressure for the plasmid encoding the tolerance. Heavy metal resistance, in some case, is present with antibiotic resistance. Therefore, heavy metal contamination of mineral water induces antibiotic resistant bacteria.

• Research in Plant Disease
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• v.28 no.3
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• pp.166-171
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• 2022

Commercial products with antibiotics like streptomycin as active ingredients have been used to control soft rot disease caused by Pectobacterium species for a long time. In this study, antibiotic resistance of twenty-seven Korean strains of Pectobacterium species including P. carotovorum, P. odoriferum, P. brasiliense, and P. parmenteri, which were previously shown to be susceptible to the bacteriophage phiPccP-1 was surveyed using a disk diffusion assay. While all strains were highly susceptible to ampicillin, kanamycin, chloramphenicol, tetracycline, and rifampicin, some strains showed weak susceptibility to 300 ㎍/ml of streptomycin. Furthermore, some of them are partially or completely resistant to commercial pesticides-Buramycinand streptomycin at the concentration of 250 ㎍/ml that is recommended by the manufacturer for streptomycin-based pesticides. These results indicate the presence of streptomycin-resistant Pectobacterium strains in South Korea, and the development of antibiotic alternatives to control soft rot is needed.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.335-342
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• 2016

Staphylococcus aureus, which is generally susceptible to the involvement route in community, is mostly MSSA. However, CA-MRSA is recently increased. Abuse of antibiotics and glycopeptides may increase VISA and VRSA. This study was conducted to investigate the changes on the antibiotic resistance prevalence and antibiotic susceptibility patterns of Staphylococcus aureus isolated from the wound of patients in a university hospital for the past 10 years. This study showed that antibiotic resistance was higher in males than in females; moreover, the antibiotic resistance rates increased with age. The resistance rate for penicillin, oxacillin, erythromycin, gentamicin, clindamycin, tetracycline, ciprofloxacin, fusidic acid, trimethoprim/sulfamethoxazole, clindamycin, and rifampicin was, respectively, 97.7%, 60.5%, 57.4%, 48.8%, 41.1%, 44.2%, 44.2%, 14.7%, 13.2% and 3.9% in 2006. The resistance rate for penicillin, oxacillin, erythromycin, gentamicin, clindamycin, tetracycline, ciprofloxacin, fusidic acid, trimethoprim/sulfamethoxazole, fusidic acid, clindamycin, and rifampicin was, respectively 95.9%, 62.6%, 55.7%, 28.6%, 50.3%, 34.7%, 38.8%, 34.0%, 2.7% and 8.2% in 2016. Vancomycin, linezolid, quinupristin/dalfopristin, and teicoplanin exhibited 100% in antibiotic susceptibility. In particular, fusidic acid resistance was increased by 19.3% in 2016. Compared with 2006, the decreased point, 12.4% was susceptible and was statistically significant. Therefore, this study suggests that periodic review and understanding of microbial and antibiotic changes should continue to investigate appropriate antibiotic susceptibility.