La isolación de listeria en la industria del procesamiento de carne

Listeria monocytogenes i druge bakterijske vrste roda Listeria su koje ukoliko se nalaze u mesu i mesnim proizvodima mogu izrazito štetno djelovati na zdravlje potrošača. Zanimala nas je mogućnost aerogene kontaminacije mesa i mesnih proizvoda ovim mikroorganizmima koji čine bioaerosol. Ovaj rad proučava prisutnost bakterije Listeria monocytogenes i Listeria spp u bioaerosolu u zraku mesno-prerađivačkih objekata te važnost izbora između impakcijske ili ciklonske metode uzorkovanja zraka. Ciklonska metoda pokazuje veću osjetljivost za otkrivanje bakterije L. monocytogenes i drugih vrsta Listeria spp u uzorcima bioaerosola u zraku mesnih industrija. Ciklonskim načinom uzorkovanja bioaerosola pronašli smo prisutnost Listeria spp u 41% uzorka od čega je u 24% potvrđena prisutnost L. monocytogenes. Rezultati ukazuju na značajnu mogućnost aerogene kontaminacije mesa i mesnih proizvoda bakterijom L. monocytogenes putem bioaerosola u mesnoj industriji. Ciklonska metoda uzorkovanja zraka za otkrivanje prisutnosti L. monocytogenes u bioaerosolima pokazala se pouzdanijom od impakcijske metode.Listeria monocytogenes and other Listeria species are microorganisms which can significantly affect the health of consumers transferring by meat and meat products. Special interest was emphasized due to the possibility of aerogene contamination of meat and products with microorganisms forming bioaerosol. In this paper the presence of Listeria monocytogenes and Listeria spp and in bioaerosol in air of meat processing plants and the importance of selecting the methods of air sampling as impaction or cyclone method were studied. In experiment the cyclone method shows higher sensitivity for the detection of sampling L. monocytogenes and other Listeria spp in bioaerosols of the air in meat industry. With cyclone bioaerosol sampling method, we found the presence of Listeria spp in 41% of the sample, of which 24% of the sample confirmed on the presence of L. monocytogenes. The results show a significant potential for aerogene contamination of meat and meat products with L. monocytogenes via bioaerosol in the meat industry. Cyclonic method indicated more reliable air sampling in detecting the presence of L monocytogenes in bioaerosols compared with the impact method.Listeria monocytogenes und andere Listeriasorten sind Mikroorganismen, die mit Fleisch und Fleischerzeugnissen eingetragen werden, können äußerst negativ auf die Gesundheit der Verbraucher wirken. Wir interessierten uns für die Möglichkeit der aerogenen Kontamination von Fleisch und Fleischerzeugnissen durch Mikroorganismen aus Bioaerosol. Die Arbeit untersucht die Anwesenheit von Mikroorganismen Listeria monocytogenes und anderen Listeriasorten in Bioaerosol in der Luft der Fleischverarbeitungsobjekte sowie die Wichtigkeit der Impaktionswahl oder der Zyklonmethode der Luftmusterung. Die Zyklonmethode zeigt eine höhere Empfindsamkeit für die Entdeckung von Listeria monocytogenes und anderen Listeriasorten in den Mustern von Bioaerosol in der Luft der Fleischindustrie. Durch die Zyklonart der Luftmusterung fanden wir die Anwesenheit von Listeria in 41 % der Muster, wovon bei 24 % die Anwesenheit von Listeria monocytogenes bestätigt wurde. Die Resultate weisen auf die bedeutende Möglichkeit der aerogenen Kontamination von Fleisch und Fleischerzeugnissen mit Bakterie Listeria monocytogenes durch Bioaerosol in der Fleischindustrie hin. Die Zyklonart der Luftmusterabnahme zeigte sich verläßlicher als die Impaktionsmethode für die Entdeckung der Anwesenheit von Listeria monocytogenes in Bioaerosol.Listeria monocytogenes y otros tipos de Listerias son microorganismos que se ingestionan por los productos cárnicos y tienen una influencia fuerte y negativa sobre la salud de los consumidores. Nos interesó la posibilidad de la contaminación aerógena de la carne y los productos cárnicos por los microorganismos del bioaerosol. Este trabajo estudia la presencia del microorganismo Listerie monocytogenes y otros tipos de Listeria en las muestras del bioaerosol del aire de las plantas de procesamiento de carne y la importancia del método de muestreo de impacto o del método ciclónico del muestreo del aire. El método ciclónico muestra una mayor susceptibilidad a la detección del Listerie monocytogenes y otros tipos de Listeria en las muestras de bioaerosol en el aire de las industrias cárnicas. Usando el método ciclónico del muestreo del bioaerosol detectamos la presencia de Listeria en 41% de las muestras, de lo cual la presencia de Listerie monocytogenes fue confirmada en el 24% de muestras. Los resultados indican la posibilidad de significante contaminación aerógena de la carne y de productos cárnicos por la bacteria Listerie monocytogenes a trevés del bioaerosol en la industria cárnica. El método ciclónico del muestreo se mostró más seguro que el método de muestreo de impacto para detectar la presencia de Listerie monocytogenes en bioaerosoles

Amide containing NBTI antibacterials with reduced hERG inhibition, retained antimicrobial activity against gram-positive bacteria and in vivo efficacy

Novel bacterial topoisomerase inhibitors (NBTIs) are new promising antimicrobials for the treatment of multidrug-resistant bacterial infections. In recent years, many new NBTIs have been discovered, however most of them struggle with the same issue - the balance between antibacterial activity and hERG-related toxicity. We started a new campaign by optimizing the previous series of NBTIs, followed by the design and synthesis of a new, amide-containing focused NBTI library to reduce hERG inhibition and maintain antibacterial activity against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). This optimization strategy yielded the lead compound 12 that exhibits potent antibacterial activity against Gram-positive bacteria, reduced hERG inhibition, no cardiotoxicity in zebrafish model, and a favorable in vivo efficacy in a neutropenic murine thigh infection model of MRSA infection

Towards harmonized laboratory methodologies in veterinary clinical bacteriology: outcomes of a European survey

IntroductionVeterinary clinical microbiology laboratories play a key role in antimicrobial stewardship, surveillance of antimicrobial resistance and prevention of healthcare associated-infections. However, there is a shortage of international harmonized guidelines covering all steps of veterinary bacterial culture from sample receipt to reporting.MethodsIn order to gain insights, the European Network for Optimization of Veterinary Antimicrobial Treatment (ENOVAT) designed an online survey focused on the practices and interpretive criteria used for bacterial culture and identification (C&amp;amp;ID), and antimicrobial susceptibility testing (AST) of animal bacterial pathogens.ResultsA total of 241 microbiology laboratories in 34 European countries completed the survey, representing a mixture of academic (37.6%), governmental (27.4%), and private (26.5%) laboratories. The C&amp;amp;ID turnaround varied from 1 to 2 days (77.8%) to 3–5 days (20%), and 6– 8 days (1.6%), with similar timeframes for AST. Individual biochemical tests and analytical profile index (API) biochemical test kits or similar were the most frequent tools used for bacterial identification (77% and 56.2%, respectively), followed by PCR (46.6%) and MALDI-TOF MS (43.3%). For AST, Kirby-Bauer disk diffusion (DD) and minimum inhibitory concentration (MIC) determination were conducted by 43.8% and 32.6% of laboratories, respectively, with a combination of EUCAST and CLSI clinical breakpoints (CBPs) preferred for interpretation of the DD (41.2%) and MIC (47.6%) results. In the absence of specific CBPs, laboratories used human CBPs (53.3%) or veterinary CBPs representing another body site, organism or animal species (51.5%). Importantly, most laboratories (47.9%) only report the qualitative interpretation of the result (S, R, and I). As regards testing for AMR mechanisms, 48.5% and 46.7% of laboratories routinely screened isolates for methicillin resistance and ESBL production, respectively. Notably, selective reporting of AST results (i.e. excluding highest priority critically important antimicrobials from AST reports) was adopted by 39.5% of laboratories despite a similar proportion not taking any approach (37.6%) to guide clinicians towards narrower-spectrum or first-line antibiotics.DiscussionIn conclusion, we identified a broad variety of methodologies and interpretative criteria used for C&amp;amp;ID and AST in European veterinary microbiological diagnostic laboratories. The observed gaps in veterinary microbiology practices emphasize a need to improve and harmonize professional training, innovation, bacterial culture methods and interpretation, AMR surveillance and reporting strategies.</jats:sec

Azithromycin resistance in Escherichia coli and Salmonella from food-producing animals and meat in Europe.

OBJECTIVES To characterize the genetic basis of azithromycin resistance in Escherichia coli and Salmonella collected within the EU harmonized antimicrobial resistance (AMR) surveillance programme in 2014-18 and the Danish AMR surveillance programme in 2016-19. METHODS WGS data of 1007 E. coli [165 azithromycin resistant (MIC > 16 mg/L)] and 269 Salmonella [29 azithromycin resistant (MIC > 16 mg/L)] were screened for acquired macrolide resistance genes and mutations in rplDV, 23S rRNA and acrB genes using ResFinder v4.0, AMRFinder Plus and custom scripts. Genotype-phenotype concordance was determined for all isolates. Transferability of mef(C)-mph(G)-carrying plasmids was assessed by conjugation experiments. RESULTS mph(A), mph(B), mef(B), erm(B) and mef(C)-mph(G) were detected in E. coli and Salmonella, whereas erm(C), erm(42), ere(A) and mph(E)-msr(E) were detected in E. coli only. The presence of macrolide resistance genes, alone or in combination, was concordant with the azithromycin-resistant phenotype in 69% of isolates. Distinct mph(A) operon structures were observed in azithromycin-susceptible (n = 50) and -resistant (n = 136) isolates. mef(C)-mph(G) were detected in porcine and bovine E. coli and in porcine Salmonella enterica serovar Derby and Salmonella enterica 1,4, [5],12:i:-, flanked downstream by ISCR2 or TnAs1 and associated with IncIγ and IncFII plasmids. CONCLUSIONS Diverse azithromycin resistance genes were detected in E. coli and Salmonella from food-producing animals and meat in Europe. Azithromycin resistance genes mef(C)-mph(G) and erm(42) appear to be emerging primarily in porcine E. coli isolates. The identification of distinct mph(A) operon structures in susceptible and resistant isolates increases the predictive power of WGS-based methods for in silico detection of azithromycin resistance in Enterobacterales

Genomic insights into the emergence and spread of methicillin-resistant Staphylococcus pseudintermedius in veterinary clinics

Staphylococcus pseudintermedius is a common cause of skin and soft tissue infections in dogs but can also cause infections in cats and humans. The frequency of methicillin-resistant S. pseudintermedius (MRSP) strains is increasing worldwide. Here, we obtained 43 MRSP isolates from dogs (n = 41), one cat (n = 1) and the small animal clinic environment (n = 1) in Slovenia from the period 2008–2018, which underwent whole-genome sequencing (WGS) and antimicrobial susceptibility testing. Five sequence types (STs) were identified, with ST71 (32/43) and ST551 (8/43) being the predominant. In Slovenia, ST551 was first detected in 2016, whereas a decrease in the frequency of ST71 was observed after 2015. All isolates were multidrug-resistant and most antimicrobial-resistant phenotypes could be linked to acquisition of the corresponding resistance genes or gene mutations. Core-genome multilocus sequence typing (cgMLST) revealed several potential MRSP transmission routes: (i) between two veterinary clinics by a single MRSP-positive dog, (ii) between the environment of a veterinary clinic and a dog, and (iii) between a canine and a feline patient through the contaminated environment of a veterinary clinic. Of the six dogs that were additionally sampled from 14 days to five months after the initial sampling, each harbored the same MRSP strain, suggesting a limited within-host diversity of MRSP in symptomatic dogs. The present results highlight the importance of MRSP-positive dogs in the spread of veterinary care-associated MRSP infections and call for the implementation of strict control measures to reduce MRSP contamination in veterinary clinic environments originating from animal-contact surfaces

Source tracking on a dairy farm reveals a high occurrence of subclinical mastitis due to hypervirulent Listeria monocytogenes clonal complexes

An extensive source investigation was conducted on a dairy farm with neurolisteriosis and subclinical mastitis cases to identify infection source and potential transmission routes of Listeria monocytogenes

Retrospective investigation of listeriosis outbreaks in small ruminants using different analytical approaches for whole genome sequencing-based typing of Listeria monocytogenes

Listeria monocytogenes is the causative agent of listeriosis, a serious disease affecting both humans and animals. While listeriosis outbreaks in humans are commonly investigated in detail, routine typing of L. monocytogenes is generally not performed in animal outbreaks. Here, seven presumable listeriosis outbreaks in small ruminants were retrospectively identified based on the pulsed-field gel electrophoresis (PFGE) profiles. Outbreaks were further characterised using three different analytical approaches based on the whole-genome sequencing (WGS) data: core-genome multilocus sequence typing (cgMLST), whole-genome MLST (wgMLST) and whole-genome single nucleotide polymorphism (wgSNP) typing. A monoclonal pattern of all seven outbreaks was identified using all three approaches, indicating common-source outbreaks. The outbreak strains belonged to sequence types (STs) 1 (n = 3), ST18 (n = 1), ST21 (n = 2) and ST184 (n = 1). Two epidemiologically linked ST1 outbreaks with indistinguishable PFGE profiles showed a polyphyletic nature and differed in >78 SNPsthus, they were classified as separate outbreaks according to WGS. In ST184, the outbreak strain was also found in faeces of apparently healthy ruminants, silage and water collected from the trough, which were the most likely source(s) of infection. The outbreak-associated isolates differed in 0–7 cgMLST alleles, 0–12 wgMLST alleles and 1–13 SNPs. The minimum genetic diversity between outbreak-associated isolates and epidemiologically unrelated isolates of the same ST was low in all analysed cases, approaching the maximum diversity within the outbreak cluster. The results suggest that a fixed threshold to define the outbreak cluster should only be considered as a guide and highlight the role of epidemiological data for outbreak confirmation. The identified cgMLST clusters may be further investigated by wgMLST and/or wgSNP typing to increase confidence during investigations of outbreaks caused by highly clonal L. monocytogenes groups. This study gives an overview of the inter- and intra-outbreak genetic diversity of L. monocytogenes strains involved in animal outbreaks, hence improving their investigation

Quill injury - cause od death of captive indian crested porcupine(Hystrix indica, Kerr, 1792)

Indian crested porcupine (Hystrix indica) is a member of the family of Old World porcupines (Hystricidae). Its body is covered with multiple layers of quills, which serve for warning and attack if animal is threatened. However, the literature data on injuries caused by Indian crested porcupine are absent. We describe pathomorphological lesions in an Indian crested porcupine from the Ljubljana Zoo, which died after a fight with a younger male that caused a perforative quill injury of the thoracic wall, followed by septicaemia. Macroscopic, microscopic and bacteriological findings were detaile