Extended spectrum ß-lactamase-producing Escherichia coli among backyard poultry farms, farmers, and environments in Thailand

Food-producing animals, including poultry, have been considered as potential sources of extended spectrum ß-lactamase (ESBL)-producing Escherichia coli. This study investigates the occurrence and dissemination of ESBL-producing E. coli among backyard poultry farms, farmers, and environments in Northern Thailand. Antimicrobial-resistant phenotypes, resistant determinants, genotypic characterizations, and spread of these isolates were studied. Fecal samples from poultry, farmers, and environments were captured from 27 farms. In total, 587 samples were collected and the overall 27.1% (159/587) of ESBL-producing E. coli isolates were obtained. Among these, ESBL-producing E. coli was isolated from 50% (farmers), 25.9% poultry (24.9% chicken and 36.6% duck) of the fecal samples, and 25.0% of the environmental samples. All isolates demonstrated multidrug resistance, most frequently to ≥ 10 different antimicrobial agents. Molecular analysis of ESBL-encoding genes showed that the predominant gene was blaCTX-M-55 (54.1%), followed by blaCTX-M-14 (28.3%), and blaCTX-M-15 (8.8%). blaCTX-M-27 (3.8%) and blaCTX-M-65 (0.6%) were also detected at low frequencies. Conjugation assays demonstrated that blaCTX-M could be transferred to E. coli J53 with the transfer frequencies ranging from 10−7 to 10−2. Pulsed field gel electrophoresis (PFGE) revealed diverse genotypes, however, identical and closely related PFGE profiles were detected among isolates within and between farms, suggesting the clonal transmission. In addition, our study identified 4 blaCTX-M-27-positive E. coli B2-ST131 isolates. Interestingly, two ST131 isolates, obtained from a farmer and chicken in the same area, showed closely related PFGE profiles. Our results suggest the presence and spread of ESBL-producing E. coli between backyard poultry farms, farmers, and environments in Thailand

Risk factors for gastrointestinal colonization and acquisition of carbapenem-resistant gram-negative bacteria among patients in intensive care units in Thailand

This study was conducted to investigate the prevalence of and risk factors for colonization and acquisition of carbapenem-resistant (CR) Gram-negative bacteria (GNB) among patients admitted to intensive care units (ICUs) in two tertiary care hospitals in northern Thailand. Screening of rectal swab specimens for CR-GNB was performed on patients at ICU admission and discharge.</jats:p

Environmental dissemination of mcr-1 positive Enterobacteriaceae by Chrysomya spp. (common blowfly): An increasing public health risk

Until recently, the role of insects, and particularly flies, in disseminating antimicrobial resistance (AMR) has been poorly studied. In this study, we screened blowflies (Chrysomya spp.) from different areas near the city of Phitsanulok, Northern Thailand, for the presence of AMR genes and in particular, mcr-1, using whole genome sequencing (WGS). In total, 48 mcr-1-positive isolates were recovered, consisting of 17 mcr-1-positive Klebsiella pneumoniae (MCRPKP) and 31 mcr-1-positive Escherichia coli (MCRPEC) strains. The 17 MCRPKP were shown to be clonal (ST43) with few single poly nucleomorphs (SNPs) by WGS analysis. In in-vitro models, the MCRPKP were shown to be highly virulent. In contrast, 31 recovered MCRPEC isolates are varied, belonging to 12 different sequence types shared with those causing human infections. The majority of mcr-1 gene are located on IncX4 plasmids (29/48, 60.42%), sharing an identical plasmid backbone. These findings highlight the contribution of flies to the AMR contagion picture in low- and middle-income countries and the challenges of tackling global AMR

Risk factors for extended-spectrum β-lactamase-producing Enterobacteriaceae carriage in patients admitted to Intensive Care Unit in a Tertiary Care Hospital in Thailand

Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) are important causes of serious infections in intensive care unit (ICU). This study aimed to investigate the risk factors for intestinal carriage of ESBL-PE among patients admitted to ICU, subsequent ESBL-PE infections, and outcomes of these patients. This study prospectively collected rectal swabs from 215 ICU patients in Northern Thailand and ESBL-PE were isolated. A high prevalence of ESBL-PE carriage (134/215, 62.3%) at ICU admission was observed, with Escherichia coli representing the predominant organism (67.5%) followed by Klebsiella pneumoniae (19.4%). Multivariate logistic regression analysis identified chronic renal disease as the independent risk factor for ESBL-PE carriage (p = 0.009; adjusted odds ratio = 4.369; 95% confidence interval = 1.455–13.119). Among colonized patients, 2.2% (3/134) developed ESBL-PE infections during ICU stay. Phylogenetic analysis of E. coli (n = 108) showed that the predominant group was group A (38.0%), followed by groups B1 (17.6%), D (15.7%), B2 (14.8%), C (7.4%), and F (6.5%). Multilocus sequence typing analysis of the pathogenic groups B2, D, and F revealed 11 different sequence types (STs), with ST131 (n = 13) as the most prevalent, followed by ST648 (n = 5), ST38 (n = 4), ST393 (n = 3), and ST1193 (n = 3). These results are of concern since ESBL-PE may be a prerequisite for endogenous infections and potentially disseminate within the hospital. This is the first study describing ESBL-PE carriage among patients at ICU admission and subsequent ESBL-PE infections in Thailand