RESUMEN

BACKGROUND: Throughout a three-year study period, 1,577 bovine clinical mastitis samples and 302 bulk tank samples were analyzed from ten Brazilian dairy herds. Enterococcus spp. was isolated and identified in 93 (5.9%) clinical mastitis samples. In addition, 258 Enterococcus spp. were isolated from the bulk tank samples of the same herds. The identification of Enterococcus spp. isolated from bulk tanks and milk samples of clinical mastitis were accomplished by phenotypic characteristics and confirmed by MALDI-TOF Mass Spectrometry (MS). Fisher test was performed to verify the difference between bulk tanks and mastitis samples. RESULTS: The following species were identified from clinical mastitis: E. saccharolyticus (62.4%), E. faecalis (19.4%), E. faecium (15.1%), E. hirae (1.1%), E. mundtii (1.1%), E. durans (1.1%). Furthermore, from 258 bulk tank milk samples, eight enterococci species were isolated: E. faecalis (67.8%), E. hirae (15.1%), E. faecium (4.6%), E. saccharolyticus (4.6%), E. mundtii (3.1%), E. caseliflavus ( 2.7%), E. durans (1.2%), E. galinarum (0.8%). CONCLUSIONS: The difference in species predominance in bulk tank samples (67.8% of E. faecalis) and clinical mastitis (62.4% of E. saccharolyticus) was unexpected and caught our attention. Although Enterococcus spp. are traditionally classified as an environmental mastitis agent, in the present study, E. saccharolyticus behaved as a contagious agent of mastitis, which consequently changed the control patterns to be implemented.

Asunto(s)

Enterococcus , Mastitis Bovina , Leche , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Mastitis Bovina/microbiología , Mastitis Bovina/diagnóstico , Animales , Leche/microbiología , Leche/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Femenino , Enterococcus/aislamiento & purificación , Bovinos , Brasil , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/diagnóstico

RESUMEN

AIMS: Antibiotic resistance is a global health crisis. Roughly two-thirds of all antibiotics used are in production animals, which have the potential to impact the development of antibiotic resistance in bacterial pathogens of humans. There is little visibility on the extent of antibiotic resistance in the Australian food chain. This study sought to establish the incidence of antibiotic resistance among enterococci from poultry in Victoria. METHODS AND RESULTS: In 2016, poultry from a Victorian processing facility were swabbed immediately post-slaughter and cultured for Enterococcus species. All isolates recovered were speciated and tested for antibiotic susceptibility to 12 antibiotics following the Clinical Laboratory Standards Institute guidelines. A total of 6 farms and 207 birds were sampled and from these 285 isolates of Enterococcus were recovered. Eight different enterococcal species were identified as follows: E. faecalis (n = 122; 43%), E. faecium (n = 92; 32%), E. durans (n = 35; 12%), E. thailandicus (n = 23; 8%), E. hirae (n = 10; 3%), and a single each of E. avium, E. gallinarum, and E. mundtii. Reduced susceptibility to older classes of antibiotics was common, in particular: erythromycin (73%), rifampin (49%), nitrofurantoin (40%), and ciprofloxacin (39%). Two vancomycin-intermediate isolates were recovered, but no resistance was detected to either linezolid or gentamicin. CONCLUSIONS: The relatively high numbers of a recently described species, E. thailandicus, suggest this species might be well adapted to colonize poultry. The incidence of antibiotic resistance is lower in isolates from poultry than in human medicine in Australia. These results suggest that poultry may serve as a reservoir for older antibiotic resistance genes but is not driving the emergence of antimicrobial resistance in human bacterial pathogens. This is supported by the absence of resistance to linezolid and gentamicin.

Asunto(s)

Antibacterianos , Enterococcus , Pruebas de Sensibilidad Microbiana , Aves de Corral , Animales , Enterococcus/aislamiento & purificación , Enterococcus/efectos de los fármacos , Enterococcus/genética , Antibacterianos/farmacología , Aves de Corral/microbiología , Victoria , Incidencia , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Farmacorresistencia Bacteriana , Pollos/microbiología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/epidemiología

RESUMEN

AIMS: To investigate enterococci carrying linezolid and vancomycin resistance genes from fecal samples recovered from wild boars. METHODS AND RESULTS: Florfenicol- and vancomycin-resistant enterococci, isolated on selective agar plates, were screened by PCR for the presence of linezolid and vancomycin resistance genes. Five isolates carried optrA or poxtA linezolid resistance genes; one strain was resistant to vancomycin for the presence of vanA gene. All isolates were tested for their antibiotic susceptibility and subjected to Whole Genome Sequencing (WGS) analysis. In Enterococcus faecalis (E. faecalis) V1344 and V1676, the optrA was located on the new pV1344-optrA and pV1676-optrA plasmids, respectively, whereas in Enterococcus faecium (E. faecium) V1339 this gene was on a 22 354-bp chromosomal genetic context identical to the one detected in a human E. faecium isolate. In both E. faecium V1682 and E. durans V1343, poxtA was on the p1818-c plasmid previously found in a human E. faecium isolate. In E. faecium V1328, the vanA gene was on the Tn1546 transposon in turn located on a new pV1328-vanA plasmid. Only E. faecium V1682 successfully transferred the poxtA gene to an enterococcal recipient in filter mating assays. CONCLUSIONS: The occurrence of genetic elements carrying linezolid and vancomycin resistance genes in enterococci from wild boars is a matter of concern, moreover, the sharing of plasmids and transposons between isolates from wild animals, human, and environment indicates an exchange of genetic material between these settings.

Asunto(s)

Proteínas Bacterianas , Farmacorresistencia Bacteriana , Enterococcus faecalis , Enterococcus faecium , Sus scrofa , Animales , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Ligasas de Carbono-Oxígeno/genética , Farmacorresistencia Bacteriana/genética , Enterococcus faecalis/genética , Enterococcus faecalis/aislamiento & purificación , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/efectos de los fármacos , Heces/microbiología , Genoma Bacteriano , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Italia , Linezolid/farmacología , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Sus scrofa/microbiología , Resistencia a la Vancomicina/genética , Secuenciación Completa del Genoma

RESUMEN

Monitoring the use of antimicrobials and the emergence of resistance in animals and people is important for the control of antimicrobial resistance, and for establishing sustainable and effective disease management practices. In this study, we used Enterococcus spp. and Escherichia coli as indicator species to investigate antimicrobial susceptibility patterns and how these change over time, on ten Swedish pig farms. Indoor environmental sock sampling was performed once a month during the entire production cycle of one batch of pigs on each farm, resulting in 60 samples collected in total. Selective culture for E. coli and Enterococcus spp. resulted in 122 isolates of E. coli, 74 isolates of E. faecium, but no isolates of E. faecalis. Microdilution was used to determine minimum inhibitory concentrations for twelve antimicrobial substances in E. coli and fifteen substances in E. faecium. The overall prevalence of resistance was low. Among the E. coli isolates, the proportions non-wild type (resistant, NWT) isolates were as follows: azithromycin and amikacin 1% (n = 1), trimethoprim and sulfamethoxazole 2% (n = 3), ampicillin 6% (n = 7) and tetracycline 9% (n = 11). Among the E. faecium isolates, the NWT proportions were: teicoplanin, linezolid and gentamicin 1% (n = 1), daptomycin 3% (n = 2), erythromycin 26% (n = 19), tetracycline 27% (n = 20), quinupristin/dalfopristin 58% (n = 42). The resistance patterns differed between the farms, likely due to different antimicrobial use, biosecurity measures and source of the animals. The NWT prevalence among E. coli decreased over time, whereas no similar trend could be observed in E. faecium. The results of the current study illustrate the complex factors affecting the antimicrobial resistance patterns observed on each farm, indicating that specific practices and risk factors have an impact on the prevalence and type of antimicrobial resistance. Further studies of the farm environments in combination with antimicrobial use and other risk factor data are needed to elucidate the multifaceted drivers of antimicrobial resistance development on livestock farms.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana , Enterococcus faecium , Escherichia coli , Pruebas de Sensibilidad Microbiana , Enfermedades de los Porcinos , Animales , Enterococcus faecium/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Porcinos , Antibacterianos/farmacología , Suecia/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/epidemiología , Granjas , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Prevalencia , Crianza de Animales Domésticos/métodos

RESUMEN

Lactococcus garvieae has recently been identified and listed as one of the causative agents of hyperacute hemorrhagic sepsis in fish. In intensive recirculating aquaculture systems where there are high fish densities and minimal water changes, not only will it be conducive to the growth of bacteria, but Cryptocaryon irritans as a marine protozoan fish parasite is also prone to appear. This study reports the disease status of Trachinotus ovatus in an aquaculture area in Yangjiang City, Guangdong Province. Through the diagnosis of clinical symptoms of the diseased fish, identification of specific primers, 16s rRNA sequences phylogenetic tree analysis, physiological and biochemical identification, and observation of histopathological sections, the result of the experiment is that the mass death of T. ovatus is caused by a mixture of L. garvieae and C. irritants infections. Subsequently, regression infection experiments were performed to verify Koch's law. It was confirmed that the pathogen had strong virulence to T. ovatus. This is the first time that the co-infection of L. garvieae and C. irritans to T. ovatus was found in South China. The research results of this experiment have certain enlightenment significance for the epidemic trend of fish diseases in relevant sea areas.

Asunto(s)

Enfermedades de los Peces , Lactococcus , Filogenia , Animales , Lactococcus/genética , Lactococcus/aislamiento & purificación , Lactococcus/clasificación , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/parasitología , China , Cilióforos/genética , Cilióforos/clasificación , Cilióforos/aislamiento & purificación , Acuicultura , ARN Ribosómico 16S/genética , Coinfección/microbiología , Coinfección/parasitología , Infecciones por Cilióforos/parasitología , Infecciones por Cilióforos/veterinaria , Peces/parasitología , Peces/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria

RESUMEN

Co-infection of Lactococcus garvieae and Aeromonas hydrophila, has been confirmed from diseased Nile Tilapia (Oreochromis niloticus), Chithralada strain cultured in a freshwater rearing pond of Alappuzha district of Kerala, India. The aetiological agents behind the disease outbreak were bacteriologically proven and confirmed by 16SrRNA sequencing and phylogenetic analysis. PCR detection of the virulent genes, showed existence of adhesin and hemolysin in L. garvieae and aerolysin in A. hydrophila strain obtained. To fulfil Koch's postulates, challenge experiments were conducted and median lethal dose (LD50) of L. garvieae and A. hydrophila was calculated as 1 × 105.91 CFU per mL and 1 × 105.2 CFU per mL respectively. Histopathologically, eyes, spleen, and kidney were the predominantly infected organs by L. garvieae and A. hydrophila. Out of the 13 antibiotics tested to check antibiotic susceptibility, L. garvieae showed resistance to almost 7 antibiotics tested, with a resistance to Ciprofloxacin while A. hydrophila was found resistant to Streptomycin and Erythromycin. Understanding the complex interaction between Gram-positive and Gram-negative bacteria in the disease process and pathogenesis in fish host will contribute to efficient treatment strategies. As a preliminary investigation into this complex interaction, the present study is aimed at phenotypic and genotypic characterization, pathogenicity evaluation, and antibiotic susceptibility of the co-infecting pathogens in a diseased sample of freshwater-farmed Nile tilapia.

Asunto(s)

Aeromonas hydrophila , Antibacterianos , Cíclidos , Coinfección , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Lactococcus , Filogenia , Animales , Aeromonas hydrophila/genética , Aeromonas hydrophila/aislamiento & purificación , Aeromonas hydrophila/patogenicidad , Aeromonas hydrophila/clasificación , Aeromonas hydrophila/efectos de los fármacos , Cíclidos/microbiología , India , Enfermedades de los Peces/microbiología , Lactococcus/genética , Lactococcus/aislamiento & purificación , Lactococcus/clasificación , Lactococcus/patogenicidad , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Coinfección/microbiología , Coinfección/veterinaria , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , ARN Ribosómico 16S/genética , Acuicultura , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo

RESUMEN

Linezolid resistance in Enterococcus spp. is increasingly considered critically important and a public health threat which mandates the need to understand their genomic contents and dissemination patterns. Here, we used whole-genome sequencing to characterize the resistome, virulome and mobile genetic elements of nine linezolid-resistant (LZDR) enterococci (seven optrA-E. faecalis, one poxtA-E. faecium and one optrA-E. casseliflavus) previously obtained from the nares of healthy dogs, pigs, pig farmers and tracheal samples of nestling storks in Spain. Also, the relatedness of the isolates with publicly available genomes was accessed by core-genome single nucleotide polymorphism (SNP) analysis. The optrA gene of the E. faecalis and E. casseliflavus isolates was located downstream of the fexA gene. The optrA gene in the E. casseliflavus isolate was carried in a plasmid (pURX4962), while those in the seven E. faecalis isolates were chromosomally located. The OptrA proteins were mostly variants of wild type (DP-2: Y176D/T481P; RDK: I104R/Y176D/E256K; DD-3: Y176D/G393D; and EDD: K3E/Y176D/G393D), except two that were wild type (one E. faecalis and one E. casseliflavus). The poxtA gene in the E. faecium isolate was found alone within its contig. The cfrD was upstream of ermB gene in the E. casseliflavus isolate and flanked by ISNCY and IS1216. All the LZDR enterococci carried plasmid rep genes (2-3) containing tetracycline, chloramphenicol and aminoglycoside resistance genes. All isolates except E. casseliflavus carried at least one intact prophage, of which E. faecalis-ST330 (X4957) from a pig carried the highest (n = 5). Tn6260 was associated with lnuG in E. faecalis-ST330 while Tn554 was with fexA in E. feaecalis-ST59 isolates. All except E. casseliflavus (n = 0) carried at least two metal resistance genes (MRGs), of which poxtA-carrying E. faecium-ST1739 isolate contained the most (arsA, copA, fief, ziaA, znuA, zosA, zupT, and zur). SNP-based analyses identified closely related optrA-E. faecalis isolates from a pig and a pig farmer on the same farm (SNP = 4). Moreover, optrA- carrying E. faecalis-ST32, -ST59, and -ST474 isolates from pigs were related to those previously described from humans (sick and healthy) and cattle in Spain, Belgium, and Switzerland (SNP range 43-86). These findings strongly suggest the transmission of LZDR-E. faecalis between a pig and a pig farmer and potential inter-country dissemination. These highlight the need to strengthen molecular surveillance of LZDR enterococci in all ecological niches and body parts to direct appropriate control strategies.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana , Enterococcus , Genoma Bacteriano , Linezolid , Filogenia , Animales , Linezolid/farmacología , Porcinos/microbiología , Farmacorresistencia Bacteriana/genética , Perros , Antibacterianos/farmacología , Enterococcus/genética , Enterococcus/efectos de los fármacos , Enterococcus/aislamiento & purificación , Enterococcus/clasificación , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/transmisión , Infecciones por Bacterias Grampositivas/veterinaria , Humanos , Secuenciación Completa del Genoma , España , Polimorfismo de Nucleótido Simple , Pruebas de Sensibilidad Microbiana , Proteínas Bacterianas/genética , Genómica , Plásmidos/genética

RESUMEN

Background: Vancomycin-resistant enterococci (VRE) have become an increasing public health concern in the past few decades, being associated with serious multidrug-resistant (MDR) infections. This study was conducted to investigate the role of diarrheic pet animals as potential reservoirs for virulent extensively drug-resistant (XDR) VRE and their threat on human health. Materials and Methods: Rectal swabs were collected from 153 diarrheic pet animals (80 dogs and 73 cats). The collected swabs were cultured on CHROMagarTMVRE for the isolation of vancomycin-resistant Enterococcus faecalis and Enterococcus faecium, and then suspected colonies were identified as enterococci after Gram staining, conventional biochemical tests, and molecular techniques. VRE were basically identified using the disk diffusion method; however, molecular identification of vanA and vanB genes was carried out among confirmed VRE isolates. Moreover, three virulence genes (cytolysin A, cylA; enterococcal surface protein, esp; and hyaluronidase, hyl) were investigated in VRE isolates. Thereafter, VRE strains that harbored virulence genes were tested for antimicrobial susceptibility. Results: Eighteen out of 153 animals (11.8%) were positive for VRE, which were obtained from 15% and 8.2% of the examined dogs and cats, respectively. None of the obtained isolates carried the vanA gene, whereas the vanB gene was detected in E. faecalis (4/10) with a prevalence rate (40%). Of the obtained VRE isolates, five possessed esp and/or cylA, while all strains were negative for the hyl gene. Furthermore, four virulent VRE isolates exhibited an XDR pattern, and one isolate was MDR. Conclusion: Diarrheic pet animals could represent a potential zoonotic reservoir for virulent XDR vancomycin-resistant E. faecalis, which may have serious public health implications.

Asunto(s)

Enfermedades de los Gatos , Enfermedades de los Perros , Infecciones por Bacterias Grampositivas , Mascotas , Enterococos Resistentes a la Vancomicina , Animales , Gatos , Perros , Enfermedades de los Gatos/microbiología , Enfermedades de los Gatos/epidemiología , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Mascotas/microbiología , Enterococos Resistentes a la Vancomicina/genética , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Diarrea/microbiología , Diarrea/veterinaria , Diarrea/epidemiología , Antibacterianos/farmacología , Humanos , Enterococcus faecium/genética , Enterococcus faecium/aislamiento & purificación , Enterococcus faecium/efectos de los fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/aislamiento & purificación , Virulencia , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple , Salud Pública

RESUMEN

OBJECTIVES: The emergence of antimicrobial-resistant and mastitis-associated Enterococcus faecalis and Enterococcus faecium is of great concern due to the huge economic losses associated with enterococcal infections. Here we report the draft genome sequences of E. faecalis and E. faecium strains that were isolated from raw milk samples obtained from mastitis-infected cows in Bangladesh. METHODS: The two strains were isolated, identified, and genomic DNA was sequenced using the Illumina NextSeq 550 platform. The assembled contigs were analysed for virulence, antimicrobial resistance genes, and multilocus sequence type. The genomes were compared to previously reported E. faecalis and E. faecium genomes to generate core genome phylogenetic trees. RESULTS: E. faecalis strain BR-MHR218Efa and E. faecium strain BR-MHR268Efe belonged to multilocus sequence types ST-190 and ST-22, respectively, both of which appear to represent relatively rare sequence types. BR-MHR268Efe harboured only one antibiotic resistance gene encoding resistance towards macrolides (lsa(A)), while BR-MHR218Efa harboured ten different antibiotic resistance genes encoding resistance to aminoglycosides (ant[6]-Ia, aph(3')-III), sulphonamides (aac(6')-II), lincosamides (lnu(B)), macrolides (erm(B)), MLSB antibiotics (msr(C)), tetracyclines (tet(M), tet(L)), trimethoprim (dfrG), and pleuromutilin-lincosamide-streptogramin A (lsa(E)). Virulence gene composition was different between the two isolates. BR-MHR218Efa harboured only two virulence genes involved in adherence (acm and scm). BR-MHR268Efe harboured eight complete virulence operons including three operons involved in adherence (Ace, Ebp pili, and EfaA), two operons involved in biofilm formation (BopD and Fsr), and three exoenzymes (gelatinase, hyaluronidase, SprE). CONCLUSIONS: The genome sequences of the strains BR-MHR268Efe and BR-MHR218Efa will serve as a reference point for molecular epidemiological studies of mastitis-associated E. faecalis and E. faecium. Additionally, the findings will help understand the complex antimicrobial-resistance in livestock-assoiated Enterococci.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Enterococcus faecalis , Enterococcus faecium , Genoma Bacteriano , Infecciones por Bacterias Grampositivas , Mastitis Bovina , Tipificación de Secuencias Multilocus , Filogenia , Animales , Bovinos , Mastitis Bovina/microbiología , Enterococcus faecium/genética , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Femenino , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Enterococcus faecalis/genética , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/aislamiento & purificación , Antibacterianos/farmacología , Bangladesh , Leche/microbiología , Virulencia/genética , Pruebas de Sensibilidad Microbiana , Factores de Virulencia/genética , Secuenciación Completa del Genoma , Análisis de Secuencia de ADN

RESUMEN

Enterococcus spp. are normal intestinal tract microflorae found in poultry. However, the last decades have shown that several species, e.g., Enterococcus cecorum, have become emerging pathogens in broilers and may cause numerous losses in flocks. In this study, two combinations (H1 and H2) of menthol, 1,8-cineol, linalool, methyl salicylate, γ-terpinene, p-cymene, trans-anethole, terpinen-4-ol and thymol were used in an in vitro model, analyzing its effectiveness against the strains E. cecorum, E. faecalis, E. faecium, E. hirae and E. gallinarum isolated from broiler chickens from industrial farms. To identify the isolated strains classical microbiological methods and VITEK 2 GP cards were used. Moreover for E. cecorum a PCR test was used.. Antibiotic sensitivity (MIC) tests were performed for all the strains. For the composition H1, the effective dilution for E. cecorum and E. hirae strains was 1:512, and for E. faecalis, E. faecium and E. gallinarum, 1:1024. The second mixture (H2) showed very similar results with an effectiveness at 1:512 for E. cecorum and E. hirae and 1:1024 for E. faecalis, E. faecium and E. gallinarum. The presented results suggest that the proposed composition is effective against selected strains of Enterococcus in an in vitro model, and its effect is comparable to classical antibiotics used to treat this pathogen in poultry. This may suggest that this product may also be effective in vivo and provide effective support in the management of enterococcosis in broiler chickens.

Asunto(s)

Antibacterianos , Pollos , Enterococcus , Pruebas de Sensibilidad Microbiana , Animales , Pollos/microbiología , Enterococcus/efectos de los fármacos , Enterococcus/genética , Enterococcus/aislamiento & purificación , Antibacterianos/farmacología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/tratamiento farmacológico , Probióticos/farmacología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico

RESUMEN

Oxazolidinones are potent antimicrobial agents used to treat human infections caused by multidrug-resistant Gram-positive bacteria. The growing resistance to oxazolidinones poses a significant threat to public health. In August 2021, a linezolid-resistant Enterococcus faecium BN83 was isolated from a raw milk sample of cow in Inner Mongolia, China. This isolate exhibited a multidrug resistance phenotype and was resistant to most of drugs tested including linezolid and tedizolid. PCR detection showed that two mobile oxazolidinones resistance genes, optrA and poxtA, were present in this isolate. Whole genome sequencing analysis revealed that the genes optrA and poxtA were located on two different plasmids, designated as pBN83-1 and pBN83-2, belonging to RepA_N and Inc18 families respectively. Genetic context analysis suggested that optrA gene on plasmid pBN83-1 was located in transposon Tn6261 initially found in E. faecalis. Comprehensive analysis revealed that Tn6261 act as an important horizontal transmission vector for the spread of optrA in E. faecium. Additionally, poxtA-bearing pBN83-2 displayed high similarity to numerous plasmids from Enterococcus of different origin and pBN83-2-like plasmid represented a key mobile genetic element involved in movement of poxtA in enterococcal species. The presence of optrA- and poxtA-carrying E. faecium in raw bovine milk represents a public health concern and active surveillance is urgently warranted to investigate the prevalence of oxazolidinone resistance genes in animal-derived food products.

Asunto(s)

Antibacterianos , Enterococcus faecium , Leche , Oxazolidinonas , Animales , Bovinos , Enterococcus faecium/genética , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Leche/microbiología , China/epidemiología , Oxazolidinonas/farmacología , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Bacteriana Múltiple/genética , Plásmidos/genética , Linezolid/farmacología , Secuenciación Completa del Genoma , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/epidemiología , Genes Bacterianos/genética

RESUMEN

Wild birds could be a reservoir of medically relevant microorganisms, particularly multidrug-resistant Enterococcus spp. Resistant bacteria's epidemiology and transmission between animals and humans has grown, and their zoonotic potential cannot be ignored. This is the first study to evaluate the status of vancomycin resistant enterococci (VRE) in various wild bird species using meta-analysis and a systematic review. In this study, the pooled prevalence was obtained by analyzing data from published articles on the occurrence of VRE in wild bird species. It's unclear how the antibiotic resistance gene transfer cycle affects wild birds. Google Scholar and PubMed were used to conduct the research. The data and study methodology was assessed and extracted by two reviewers independently, with a third reviewing the results. Heterogeneity between study and publication bias were analyzed using the random effect model. Thirty-eight studies were included in the meta-analysis. 382 out of the 4144 isolates tested, were VRE. The pooled prevalence of VRE among wild birds was estimated at 11.0% (95% CI; 6.9 -17.2%; I2 = 93.204%; P < 0.001). There was high variability between study (t2 = 2.156; heterogeneity I2 = 93.204% with chi-square (Q) = 544.413, degrees of freedom (df) = 37, and P < 0.001). Egger's test verified the funnel plot's bias, while result from the leave-one-out forest plot had no effect on the pooled prevalence.

Asunto(s)

Animales Salvajes , Aves , Infecciones por Bacterias Grampositivas , Enterococos Resistentes a la Vancomicina , Animales , Animales Salvajes/microbiología , Aves/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Prevalencia , Enterococos Resistentes a la Vancomicina/aislamiento & purificación

RESUMEN

Piscine lactococcosis is a significant threat to cultured and wild fish populations worldwide. The disease typically presents as a per-acute to acute hemorrhagic septicemia causing high morbidity and mortality, recalcitrant to antimicrobial treatment or management interventions. Historically, the disease was attributed to the gram-positive pathogen Lactococcus garvieae. However, recent work has revealed three distinct lactococcosis-causing bacteria (LCB)-L. garvieae, L. petauri, and L. formosensis-which are phenotypically and genetically similar, leading to widespread misidentification. An update on our understanding of lactococcosis and improved methods for identification are urgently needed. To this end, we used representative isolates from each of the three LCB species to compare currently available and recently developed molecular and phenotypic typing assays, including whole-genome sequencing (WGS), end-point and quantitative PCR (qPCR) assays, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), API 20 Strep and Biolog systems, fatty acid methyl ester analysis (FAME), and Sensititre antimicrobial profiling. Apart from WGS, sequencing of the gyrB gene was the only method capable of consistent and accurate identification to the species and strain level. A qPCR assay based on a putative glycosyltransferase gene was also able to distinguish L. petauri from L. garvieae/formosensis. Biochemical tests and MALDI-TOF MS showed some species-specific patterns in sugar and fatty acid metabolism or protein profiles but should be complemented by additional analyses. The LCB demonstrated overlap in host and geographic range, but there were relevant differences in host specificity, regional prevalence, and antimicrobial susceptibility impacting disease treatment and prevention. IMPORTANCE: Lactococcosis affects a broad range of host species, including fish from cold, temperate, and warm freshwater or marine environments, as well as several terrestrial animals, including humans. As such, lactococcosis is a disease of concern for animal and ecosystem health. The disease is endemic in European and Asian aquaculture but is rapidly encroaching on ecologically and economically important fish populations across the Americas. Piscine lactococcosis is difficult to manage, with issues of vaccine escape, ineffective antimicrobial treatment, and the development of carrier fish or biofilms leading to recurrent outbreaks. Our understanding of the disease is also widely outdated. The accepted etiologic agent of lactococcosis is Lactococcus garvieae. However, historical misidentification has masked contributions from two additional species, L. petauri and L. formosensis, which are indistinguishable from L. garvieae by common diagnostic methods. This work is the first comprehensive characterization of all three agents and provides direct recommendations for species-specific diagnosis and management.

Asunto(s)

Enfermedades de los Peces , Infecciones por Bacterias Grampositivas , Lactococcus , Lactococcus/genética , Lactococcus/aislamiento & purificación , Lactococcus/clasificación , Animales , Enfermedades de los Peces/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Peces/microbiología , Secuenciación Completa del Genoma , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción

RESUMEN

Lactococcus garvieae is a fish pathogen that can cause diseases in humans and cows. Two genetically related species, Lactococcus formosensis and Lactococcus petauri, may be misidentified as L. garvieae. It is unclear if these species differ in host specificity and virulence genes. This study analyzed the genomes of 120 L. petauri, 53 L. formosensis, and 39 L. garvieae isolates from various sources. The genetic diversity and virulence gene content of these isolates were compared. The results showed that 77 isolates previously reported as L. garvieae were actually L. formosensis or L. petauri. The distribution of the three species varied across different collection sources, with L. petauri being predominant in human infections, human fecal sources, and rainbow trout, while L. formosensis was more common in bovine isolates. The genetic diversity of isolates within each species was high and similar. Using a genomic clustering method, L. petauri, L. formosensis, and L. garvieae were divided into 45, 22, and 13 clusters, respectively. Most rainbow trout and human isolates of L. petauri belonged to different clusters, while L. formosensis isolates from bovine and human sources were also segregated into separate clusters. In L. garvieae, most human isolates were grouped into three clusters that also included isolates from food or other sources. Non-metric multidimensional scaling ordination revealed the differential association of 15 virulence genes, including 14 adherence genes and a bile salt hydrolase gene, with bacterial species and certain collection sources. In conclusion, this work provides evidence of host specificity among the three species. IMPORTANCE: Lactococcus formosensis and Lactococcus petauri are two newly discovered bacteria, which are closely related to Lactococcus garvieae, a pathogen that affects farmed rainbow trout, as well as causes cow mastitis and human infections. It is unclear whether the three bacteria differ in their host preference and the presence of genes that contribute to the development of disease. This study shows that L. formosensis and L. petauri were commonly misidentified as L. garvieae. The three bacteria showed different distribution patterns across various sources. L. petauri was predominantly found in human infections and rainbow trout, while L. formosensis was more commonly detected in cow mastitis. Fifteen genes displayed a differential distribution among the three bacteria from certain sources, indicating a genetic basis for the observed host preference. This work indicates the importance of differentiating the three bacteria in diagnostic laboratories for surveillance and outbreak investigation purposes.

Asunto(s)

Variación Genética , Genoma Bacteriano , Especificidad del Huésped , Lactococcus , Animales , Lactococcus/genética , Lactococcus/clasificación , Lactococcus/aislamiento & purificación , Humanos , Bovinos , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/veterinaria , Factores de Virulencia/genética , Filogenia , Oncorhynchus mykiss/microbiología , Genómica , Virulencia/genética , Heces/microbiología

RESUMEN

OBJECTIVE: Acute mortality with clinical symptoms of streptococcal-like infections was observed in red tilapia Oreochromis sp. cultured in floating cages in Prachin Buri Province, Thailand, during May 2023. Herein, we identified an emerging pathogen, Lactococcus garvieae, as the etiological agent. METHODS: After bacterial isolation from the brain and kidney of diseased fish, identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and the VITEK 2 system. Sequencing of the 16S ribosomal RNA (rRNA) gene and phylogenetic analysis were applied to confirm bacterial species. Antimicrobial susceptibility testing was conducted. Histopathological findings in the brain, kidney, spleen, liver, and heart were evaluated. RESULT: From 20 fish samples, L. garvieae (n = 18 isolates) and Streptococcus agalactiae (n = 2 isolates) were identified. A phylogenetic tree of the 16S rRNA gene revealed that Thai isolates of either L. garvieae or S. agalactiae clustered with reference piscine isolates from intercontinental locations. Our isolates showed resistance against quinolones while being susceptible to other antimicrobials. Histopathological changes demonstrated severe septicemic conditions, with more invasive lesions-especially in the heart and liver-being apparent in L. garvieae-infected fish compared to S. agalactiae-infected fish. CONCLUSION: This study represents the first reported outbreak of L. garvieae with a concurrent S. agalactiae infection in farmed red tilapia in Thailand.

Asunto(s)

Enfermedades de los Peces , Infecciones por Bacterias Grampositivas , Lactococcus , Filogenia , Infecciones Estreptocócicas , Streptococcus agalactiae , Animales , Streptococcus agalactiae/aislamiento & purificación , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/genética , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/epidemiología , Tailandia/epidemiología , Lactococcus/aislamiento & purificación , Lactococcus/clasificación , Lactococcus/genética , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Tilapia/microbiología , Cíclidos , ARN Ribosómico 16S/genética

RESUMEN

Lactococcus garvieae is the causative agent of lactococcosis in fish and an emerging zoonotic pathogen with high levels of antimicrobial resistance. We report a case of L. garvieae-associated septicemia in a central bearded dragon (Pogona vitticeps) confirmed via whole-blood PCR and direct sequencing. Following a 30-d course of ceftazidime (20 mg/kg IM q72h), the animal's clinical condition had not resolved; leukopenia persisted, with heterophil toxic change. Coelomic ultrasound findings were consistent with preovulatory follicular stasis, folliculitis, and coelomitis. Following surgical ovariectomy and an additional 30-d course of ceftazidime, the animal's behavior and appetite returned to normal, the animal tested negative via whole-blood PCR assay, and the CBC was unremarkable. To our knowledge, L. garvieae with L. garvieae-associated clinical disease has not been reported previously in a bearded dragon. We conclude that L. garvieae should be considered as a possible etiologic agent in cases of septicemia in bearded dragons, with the potential for zoonotic transmission warranting further investigation.

Asunto(s)

Infecciones por Bacterias Grampositivas , Lactococcus , Lagartos , Sepsis , Animales , Antibacterianos/uso terapéutico , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/diagnóstico , Lactococcus/aislamiento & purificación , Lagartos/microbiología , Sepsis/veterinaria , Sepsis/microbiología

RESUMEN

Worldwide outbreaks make infections with pathogenic strains of Enterococcus cecorum (EC) one of the most important diseases in the broiler industry. Although research has increased knowledge about the pathogen, the transmission is not fully understood. Samples from different locations were collected from two broiler farms in Germany over a total of six production cycles. Samples were collected at days 1, 5, 10, 15, 21, 27, 34, 41 post-hatch and after cleaning and disinfection (C&D). A total of 1017 samples were collected from 25 different locations on the farms. Samples were analysed in the laboratory for EC by quantitative real-time PCR. Overall, 7.5% of the samples were positive. The probabilities for positive and negative samples did not differ between the farms. The number of findings differed significantly between the cycles. Compared to other samples, the chances of detecting EC in faecal samples were significantly higher. Most positive samples were found in the last week of the production periods, indicating an accumulation of EC in the barn environment. After C&D, positive PCR results were obtained in four out of 14 locations. A re-introduction from contaminated environment seemed possible. However, one pooled faecal sample was positive 1 day post-hatch. The locations that showed positive results after C&D and the positive faecal sample 1 day post-hatch indicated the persistence of EC in broiler houses of clinically healthy flocks that could lead to potential horizontal transmission routes. The present study detected potential EC sources and may help to improve hygienic measures to avoid transmissions.RESEARCH HIGHLIGHTSMethodology is suitable to detect EC during production and after C&D.Locations were detected that may serve as a reservoir for EC.Cycles with fewer positive samples were observed.Cleaning and disinfection had a major impact on the detection of EC.

Asunto(s)

Pollos , Enterococcus , Heces , Infecciones por Bacterias Grampositivas , Vivienda para Animales , Enfermedades de las Aves de Corral , Animales , Pollos/microbiología , Heces/microbiología , Enterococcus/aislamiento & purificación , Enterococcus/genética , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/transmisión , Alemania/epidemiología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Desinfección , Microbiología Ambiental

RESUMEN

OBJECTIVES: To investigate the global distribution of an optrA-harbouring linezolid-resistant Enterococcus faecalis ST476 clonal lineage. METHODS: Comprehensive searches of the NCBI database were performed to identify published peer-reviewed articles and genomes of E. faecalis ST476. Each genome was analysed for resistome, virulome, OptrA variant and optrA genetic contexts. A phylogenetic comparison of ST476 genomes with publicly available genomes of other STs was also performed. RESULTS: Sixty-six E. faecalis ST476 isolates from 15 countries (China, Japan, South Korea, Austria, Denmark, Spain, Czech Republic, Colombia, Tunisia, Italy, Malaysia, Belgium, Germany, United Arab Emirates and Switzerland) mainly of human and animal origin were identified. Thirty available ST476 genomes compared with genomes of 591 STs indicated a progressive radiation of E. faecalis STs starting from ST21. The closest ancestral node for ST476 was ST1238. Thirty E. faecalis ST476 genomes exhibited 3-916 SNP differences. Several antimicrobial resistance and virulence genes were conserved among the ST476 genomes. The optrA genetic context exhibited a high degree of or complete identity to the chromosomal transposon Tn6674. Only three isolates displayed an optrA-carrying plasmid with complete or partial Tn6674. The WT OptrA protein was most widespread in the ST476 lineage. CONCLUSIONS: Linezolid-resistant optrA-carrying E. faecalis of the clonal lineage ST476 is globally distributed in human, animal and environmental settings. The presence of such an emerging clone can be of great concern for public health. Thus, a One Health approach is needed to counteract the spread and the evolution of this enterococcal clonal lineage.

Asunto(s)

Enterococcus faecium , Infecciones por Bacterias Grampositivas , Animales , Humanos , Linezolid/farmacología , Antibacterianos/farmacología , Enterococcus faecalis , Filogenia , Farmacorresistencia Bacteriana/genética , Enterococcus , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Enterococcus faecium/genética , Pruebas de Sensibilidad Microbiana

Asunto(s)

Enterococcus faecium , Infecciones por Bacterias Grampositivas , Animales , Enterococcus faecium/genética , Mascotas , Brasil/epidemiología , Antibacterianos/farmacología , Células Clonales , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/veterinaria , Proteínas Bacterianas , Ligasas de Carbono-Oxígeno , Pruebas de Sensibilidad Microbiana

RESUMEN

RESEARCH HIGHLIGHTS: Egg albumen inhibits Enterococcus cecorum cloaca strains more than lesion strains.Enterococcus cecorum lesion strains are resistant to high concentrations of lysozyme.Lysozyme resistance could enhance survival in albumen and body fluids.

Asunto(s)

Enterococcus , Infecciones por Bacterias Grampositivas , Enfermedades de las Aves de Corral , Animales , Pollos , Muramidasa , Cloaca , Infecciones por Bacterias Grampositivas/veterinaria