Genetic Features of mcr-1 Mediated Colistin Resistance in CMY-2-Producing Escherichia coli From Romanian Poultry

© Copyright © 2019 Maciuca, Cummins, Cozma, Rimbu, Guguianu, Panzaru, Licker, Szekely, Flonta, Djordjevic and Timofte. Colistin is a last resort antibiotic used for the treatment of human infections associated with carbapenemase-producing Enterobacteriales. Here, we evaluated the occurrence of mcr-1 and -2 plasmid-mediated colistin resistance in colistin and/or carbapenem resistant human clinical Enterobacteriales and other gram-negative bacteria (n = 543) as well as third generation cephalosporin-resistant (3GCR) Escherichia coli isolates from poultry abattoir workers (n = 15) and poultry fecal samples (n = 92) collected from two geographically separate abattoirs in Romania. which revealed that mcr-1 was present within four sequence types (STs): ST744 (n = 7), ST57 (n = 7), ST156 (n = 2), and ST10 (n = 1). Within STs, serotypes were conserved and, notably, all except one of the mcr-1-positive isolates were found to exhibit fluoroquinolone-resistance (FQR) associated SNPs in both gyrA and parC. While there were variations in genotypes, all isolates belonging to ST744, ST57, and ST156 were rich in resistance determinants, carrying aminoglycoside-modifying enzymes genes, sulfonamide resistance gene blaTEM–1 as well as blaCMY–2 AmpC β-lactamase resistance genes. They also exhibited high similarity in carriage of virulence genes; ST10, however, only carried the mcr-1 gene. Whole genome sequencing (WGS) analysis also revealed that although the mcr-1 gene was identified in a diverse population of E. coli, two STs (ST57 and ST744) predominated and interestingly, were found in isolates across both abattoirs providing evidence for clonal transmission. Also, two main genomic contexts of mcr-1 isolates were revealed with all ST57 isolates harboring the mcr-1 gene between two copies of ISApl1 (or the Tn6330 transposon) whilst a common mcr-1 containing scaffold, highly similar to IncX type mcr-1-bearing plasmids (pWI2-mcr, Accession number: LT838201), was present among mcr-1 isolates of varying phylogenetic backgrounds (ST10, ST744 and ST156). The high prevalence of the mcr-1 gene in poultry E. coli isolates with co-resistance to cephalosporins and quinolones, in a country where antimicrobial use in food production species is poorly regulated, is concerning and the findings from this study should lead to better surveillance of antimicrobial resistance (AMR) in food-production animals in Romania

Red mouth disease in rainbow trout (Oncorhynchus mykiss) – a case report on lake trout farm from Bicaz, Romania.

Yersiniosis or red mouth disease is a contagious infectious disease of salmonids caused by the bacterium Yersinia ruckeri, which lead to significant economic losses in trout aquaculture worldwide. Sources of infection are the sick fish and asymptomatic carriers, which eliminates yersiniosis faeces, causing contamination of water and feed. Triggers the disease was in March, the surge in water temperature values of 15-170 C. The fish affected were the younger with low immune system, the sudden departure of the winter period. Histological examinations, immunohistochemical and bacteriological made from liver, spleen, kidney and blood of the trout heart yersiniosis suspects resulted in the identification of the species bacterium Yersinia ruckeri strain, confirming the suspected diagnosis based on clinical investigations (pronounced anemia of mouth and gills mucosa, dark color of skin, bleeding on the lingual mucosa, protruding eye bleeding). Bacteriological confirmation was done by identifying the causative agent, based on morphological characters (gram negative bacilli, mobile) and the distinctive biochemical characters tested using the API rapid tests. Histological examinations revealed colonies of bacteria in liver, spleen and kidneys were confirmed to be colonies of Yersinia ruckeri by immunohistochemistry with anti-Yersinia ruckeri. Antibiogram revealed sensitivity of Yersinia ruckeri at: Oxytetracycline, Flumequin, Trimethoprim and Ceftiofur, and moderate susceptibility to Amoxicillin and Enrofloxacin

Investigations in associated protozoa-bacterial infections of cyprinids from a fish farm situated on the Jijia river in N-E of Romania

In autumn 2011 in cyprinid farms located in Iasi on the Jijia river, several infections with bacterial strains and macroscopical external cysts on the skin were diagnosedwhich developed as a result of the stress induced by biotic and abiotic factors. On the examination of the cyst contents the presence of numerous spores was observed, mostly of the Dermocystidium sp genusThe samples were taken from the common carp (Cyprinus carpio) and crucian carp (Carassius auratus gibelio) species from the fish farm as well as from the Jijia River. 35 fish were examined, all of them showing cysts, fragmentation of their dorsal fin and congestion of the gills. Histological examination of the skin showed a field of multiple dermal cysts with round light eosinophilic formations (14-16µm) containing a central refractable body similar to that reported for Dermocystidium sp. Gills samples were taken from the affected areas for the SEM examination with the purpose of evaluating not only aspects of normal morphology, but also aspects of some modifications of the affected areas as well as the presence of the etiologically incriminated bacteria Pseudomonas fluorescens. The isolates were identified through phenotypic methods. All the strains that showed mobility and oxidase-positivity were tested using API 20 NE strip. Consequently, they were taxonomically grouped into the species Pseudomonas fluorescens. The scanning electron microscope (SEM) was used for the first time in the characterization of the bacterial lesions produced by Pseudomonas strains on Cyprinus carpio and Carassius auratus gibelio gills. The diagnosis of septicemia with conditional pathogen species of Pseudomonas fluorescens was correlated with the results of the physico-chemical investigations of water and the data concerning the breeding conditions of the investigated livestock