Globally, rates of ESBL-producing Enterobacteriaceae are rising We undertook a literature review, and present the temporal trends in blaCTX-M epidemiology, showing that blaCTX-M-15 and blaCTX-M-14 have displaced other genotypes in many parts of the world Explanations for these changes can be attributed to: (i) horizontal gene transfer (HGT) of plasmids; (ii) successful Escherichia coli clones; (iii) ESBLs in food animals; (iv) the natural environment; and (v) human migration and access to basic sanitation We also provide explanations for the changing epidemiology of blaCTX-M-2 and blaCTX-M-27 Modifiable anthropogenic factors, such as poor access to basic sanitary facilities, encourage the spread of blaCTX-M and other antimicrobial resistance (AMR) genes, such as blaNDM, blaKPC and mcr-1 We provide further justification for novel preventative and interventional strategies to reduce transmission of these AMR genes

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Global epidemiology of CTX-M β-lactamases: temporal and geographical shifts in genotype.

Antibiotic resistance (ABR) is recognized as a One Health challenge because of the rapid emergence and dissemination of resistant bacteria and genes among humans, animals and the environment on a global scale. However, there is a paucity of research assessing ABR contemporaneously in humans, animals and the environment in low-resource settings. This critical review seeks to identify the extent of One Health research on ABR in low- and middle-income countries (LMICs). Existing research has highlighted hotspots for environmental contamination; food-animal production systems that are likely to harbour reservoirs or promote transmission of ABR as well as high and increasing human rates of colonization with ABR commensal bacteria such as Escherichia coli However, very few studies have integrated all three components of the One Health spectrum to understand the dynamics of transmission and the prevalence of community-acquired resistance in humans and animals. Microbiological, epidemiological and social science research is needed at community and population levels across the One Health spectrum in order to fill the large gaps in knowledge of ABR in low-resource settings.

https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2018.0332

Human, animal and environmental contributors to antibiotic resistance in low-resource settings: integrating behavioural, epidemiological and One Health approaches

This study aimed to investigate the prevalence, serotype distribution, and antibiotic resistance, and to characterize the extended spectrum β-lactamases (ESBLs) producing Salmonella isolates from chicken and pork meats from retail markets in Guangdong province, China A total of 903 retail meat samples (475 chicken and 428 pork meats) were obtained from six cities (Guangzhou, Shenzhen, Heyuan, Shaoguan, Foshan, and Yunfu) of Guangdong province between May 2016 and April 2017 High levels of Salmonella contamination were detected in chicken (302/475, 636%) and pork (313/428, 731%) Thirty-eight serotypes were identified in 615 detected Salmonella, and the serotypes varied greatly between chicken and pork samples Agona (55/302, 182%), Corvallis (45/302, 149%), Kentucky (38/302, 126%), Mbandaka (32/302, 106%) was the dominant serotypes in chicken samples However, Typhimurium (78/313, 249%), Rissen (67/313, 241%), Derby (66/313, 211%), and London (48, 153%) were the most common in pork samples High rates of antibiotic resistance were found to sulfisoxazole (468/615, 761%), tetracycline (463/615, 753%), ampicillin (295/615, 480%), and ofloxacin (275/615, 447%) Notably, antimicrobial susceptibility tests identified resistance to polymyxin B (12/615, 20%) and imipenem (3/615, 05%) Multidrug-resistance (MDR) was detected in Salmonella isolated from chicken (245/302, 811%) and pork (229/313, 732%) The resistance rate of different Salmonella serotypes varied widely Especially, isolates such as Typhimurium, Agona, Corvallis and Kentucky exhibited highly resistance to antibiotics The MDR rate of Salmonella isolates from chicken was significantly higher than that from pork isolates (P < 005) Twenty-one Salmonella isolates were identified as ESBLs-producing, covering six Salmonella serotypes and displaying different pulse field gel electrophoresis (PFGE) genotypes BlaOXA-1 was the dominant ESBLs gene (9/21, 429%), followed by blaCTX-M-55 (5/21, 238%) This study indicated that Salmonella was widespread in chicken and pork from retail markets in Guangdong province and the isolates showed high multidrug-resistance, especially the known multidrug-resistant Salmonella serotypes Therefore, it is important to focus on Salmonella serotypes and strengthen the long-term monitoring of MDR Salmonella serotypes in animal-derived foods

/pdf/highly-prevalent-multidrug-resistant-salmonella-from-chicken-3puko3mt72.pdf

Highly Prevalent Multidrug-Resistant Salmonella From Chicken and Pork Meat at Retail Markets in Guangdong, China.

The prevalence and characterization of antibiotic-resistant and virulent Escherichia coli strains in the municipal wastewater system and their environmental fate.

Fluoroquinolones (FQs) are fully synthetic broad-spectrum antibacterial agents that are becoming increasingly popular in the treatment of clinical and veterinary infections. Being excreted during treatment, mostly as active compounds, their biological action is not limited to the therapeutic site, but it is moved further as resistance selection pressure into the environment. Water environment is an ideal medium for the aggregation and dissemination of antibiotics, antibiotic-resistant bacteria (ARB), and antibiotic resistance genes (ARGs), which can pose a serious threat to human health. Because of this, the aim of this study was to determine the number of fluoroquinolone-resistant bacteria (FQRB) and their share in total heterotrophic plate counts (HPC) in treated wastewater (TWW), and upstream and downstream river water (URW, DRW) samples where TWW is discharged. The spread of plasmid-mediated quinolone resistance (PMQR) determinants and the presence/absence of resistance genes to other most popular antibiotic groups (against tetracyclines and beta-lactams) in selected 116 multiresistant isolates were investigated. The share of FQRB in total HPC in all samples was rather small and ranged from 0.7 % in URW samples to 7.5 % in TWW. Bacteria from Escherichia (25.0 %), Acinetobacter (25.0 %), and Aeromonas (6.9 %) genera were predominant in the FQRB group. Fluoroquinolone resistance was mostly caused by the presence of the gene aac(6')-1b-cr (91.4 %). More rarely reported was the occurrence of qnrS, qnrD, as well as oqxA, but qnrA, qnrB, qepA, and oqxB were extremely rarely or never noted in FQRB. The most prevalent bacterial genes connected with beta-lactams' resistance in FQRB were bla TEM, bla OXA, and bla CTX-M. The bla SHV was less common in the community of FQRB. The occurrence of bla genes was reported in almost 29.3 % of FQRB. The most abundant tet genes in FQRB were tet(A), tet(L), tet(K), and tet(S). The prevalence of tet genes was observed in 41.4 % of FQRB. The highest prevalence of multidrug-resistant (MDR) microorganisms was detected in TWW and DRW samples. It indicates that discharged TWW harbors multiresistant bacterial strains and that mobile PMQR and ARGs elements may have a selective pressure for species affiliated to bacteria in the river water.

/pdf/prevalence-of-plasmid-mediated-multidrug-resistance-74b4pejq7z.pdf

Prevalence of plasmid-mediated multidrug resistance determinants in fluoroquinolone-resistant bacteria isolated from sewage and surface water.

The dissemination of drug-resistant bacteria into different environments has posed a grave threat to public health, but data on the spread of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) from animal farms to the receiving river are limited. Here, 57 ESBL-producing E. coli isolated from a pig farm and the receiving river were analyzed in terms of drug resistance, ESBL genes, and enterobacterial repetitive intergenic consensus (ERIC). The results showed that ESBL-producing E. coli from swine feces and downstream water of the pig farm outfall overlapped substantially in drug resistance and ESBL genes. Additionally, six ESBL-producing E. coli from the downstream water exhibited 100 % genetic similarity with strains from the swine feces. In conclusion, effluents of animal farms are a likely contributor to the presence of ESBL-producing E. coli in aquatic environments.

Spread of extended-spectrum beta-lactamase-producing Escherichia coli from a swine farm to the receiving river

This study aimed to investigate antimicrobial resistance and molecular epidemiology of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli) isolated from outpatients in town hospitals of Shandong province, China. Antimicrobial susceptibility of ESBL-producing E. coli was tested using the disk diffusion and resistance genes encoding for β-lactamases (blaTEM, blaCTXM, and blaSHV) were detected by polymerase chain reaction (PCR). Multilocus sequence typing (ST) of ESBL-producing E. coli was analyzed in this study. Our results showed that of 320 E. coli isolates, 201 carried ESBL genes (201/320, 62.8％), and these isolates all carried blaCTX-M genes, the most common being blaCTX-M-14 (116/201, 57.7％), followed by blaCTX-M-55 (47/201, 23.4％) and blaCTX-M-15 (31/201, 15.4％). ESBL-producing E. coli exhibited highly resistant to penicillin derivatives, fluoroquinolones, folate pathway inhibitors, and third-generation cephalosporins, but no carbapenem-resistant isolates were found in this study. Forty-two STs were found among the 201 ESBL-producing E. coli, and the most common ST was ST131 (27/201, 13.4％), followed by ST405 (19/201, 9.5％) and ST69 (15/201, 7.5％). Taken together, a high isolation rate of ESBL-producing E. coli (62.8％) was found among outpatients in town hospitals. blaCTX-M gene was most dominant and was composed of a variety of subtypes. No dominant ST was detected among ESBL-producing E. coli, indicating that these ESBL-producing E. coli isolates derive from different clones.

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Antimicrobial Resistance and Molecular Epidemiology of ESBL-Producing Escherichia coli Isolated from Outpatients in Town Hospitals of Shandong Province, China.

Background. Hepatitis E virus (HEV) is a significant pathogen of viral hepatitis and can be transmitted through fecal-oral route. Epidemiological data concerning HEV in goats, however, are relatively sparse to date. Here, the prevalence and characteristics of HEV isolated from goats at slaughterhouse were investigated in Tai’an region, China. Methods. Anti-HEV immunoglobulin G (IgG) in blood samples and HEV RNA in the liver samples were determined by using an enzyme-linked immunosorbent assay (ELISA) and a nested reverse transcription polymerase chain reaction (RT-PCR), respectively. In addition, partial nucleotide sequences of open reading frame 2 (ORF-2) of HEV isolates were analyzed. Results. Fifty goat blood samples (46.7%, 50/120) were masculine for anti-HEV IgG. HEV RNA was detected in 2 liver samples (4.0%, 2/50) and belonged to genotype 4 subtype 4 h, with high identity (91.2–93%) with cow HEV strains detected in the same province, China. Conclusions. These findings demonstrated that goats may be an important reservoir for HEV and can become a major source of HEV infection in humans via food chain.

/pdf/detection-and-characterization-of-hepatitis-e-virus-in-goats-513mp5cpgt.pdf

Detection and Characterization of Hepatitis E Virus in Goats at Slaughterhouse in Tai'an Region, China.

Prevalence and Antibiotic Resistance Profiles of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Healthy Broilers in Shandong Province, China.

The present study was aimed to determine the prevalence and characteristics of Salmonella isolated from meat samples of commercial broilers (CB) and spent hens (SH). Between March and June 2016, 200 retail raw chicken carcasses (100 from CB and 100 from SH) were obtained from local supermarkets in Tai'an city of China, and Salmonella isolates were then analyzed for antibiotic resistance, serotype, β-lactamase genes, and the presence of class 1 integron. Forty Salmonella strains were obtained in this study (CB: 21/100, 21％; SH: 19/100, 19％). Three serotypes were identified in 40 Salmonella, and S. Enteritidis (CB: 15/21, 71.4％; SH: 10/19, 52.6％) was the dominant serotype, followed by S. Typhimurium (CB: 4/21, 19％; SH: 6/19, 31.6％) and S. Derby (CB: 2/21, 9.5％; SH: 3/19, 15.8％). Among 21 Salmonella isolated from CB, high antibiotic resistance rates were found for ampicillin (20/21, 95.2％), nalidixic acid (18/21, 85.7％), cefotaxime (17/21, 81％), and tetracycline (13/21, 61.9％); class 1 integron was observed in 7 isolates (7/21, 33.3％), and gene cassettes included an empty integron (0.15kb, n=1), aadA2 (1.2kb, n=3), drfA1-aadA1 (1.4kb, n=1), and drfA17-aadA5 (1.7kb, n=2); blaTEM-1 was the dominant β-lactamase gene (21/21, 100％), followed by blaCTX-M-55 (7/21, 33.3％). Among 19 Salmonella isolated from SH, high antibiotic resistance rates were found for nalidixic acid (19/19, 100％), tetracycline (19/19, 100％), ampicillin (18/19, 94.7％), and ciprofloxacin (13/19, 68.4％); class 1 integron was observed in 2 isolates (2/19, 10.5％), and gene cassettes included drfA17-aadA5 (1.7kb, n=1) and drfA1-aadA1(1.4kb, n=1); blaTEM-1 was the dominant β-lactamase gene (19/19, 100％), followed by blaCTX-M-55 (2/19, 10.5％) and blaCMY-2 (1/19, 5.3％). Collectively, antibiotic-resistant Salmonella can be widely detected in retail raw chicken carcasses of CB and SH, and therefore can pose a serious risk to public health.

/pdf/prevalence-and-antibiotic-resistance-of-non-typhoidal-1gph11ox0n.pdf

Prevalence and Antibiotic Resistance of Non-typhoidal Salmonella Isolated from Raw Chicken Carcasses of Commercial Broilers and Spent Hens in Tai’an, China

Song Li

Papers

Spread of extended-spectrum beta-lactamase-producing Escherichia coli from a swine farm to the receiving river

Antimicrobial Resistance and Molecular Epidemiology of ESBL-Producing Escherichia coli Isolated from Outpatients in Town Hospitals of Shandong Province, China.

Detection and Characterization of Hepatitis E Virus in Goats at Slaughterhouse in Tai'an Region, China.

Prevalence and Antibiotic Resistance Profiles of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Healthy Broilers in Shandong Province, China.

Prevalence and Antibiotic Resistance of Non-typhoidal Salmonella Isolated from Raw Chicken Carcasses of Commercial Broilers and Spent Hens in Tai’an, China