Különböző eredetű Francisella tularensis törzsek összehasonlító vizsgálata = Comparative examination of Francisella tularensis strains isolated from different species in Hungary

Vizsgálataink során Magyarország közel 30 településéről összesen 67 Francisella tularensis törzset gyűjtöttünk, amely révén létrehoztunk egy hazai F. tularensis törzsgyűjteményt. Megvizsgáltunk a hazai Francisella tularensis izolátumok fenotípusos és genotípusos tulajdonságait. Jellemeztük antibiotikum-érzékenységüket, anyagcsere-ujjlenyomatukat és filogenetikai tulajdonságaikat. Jellemeztük a mezei nyúl és a mezei hörcsög populáció hazai szerológiai áthangolódását, és ezen fajokban a tularemia kórtani sajátosságait. | Altogether 67 Francisella tularensis isolates were collected from 30 settlements from different geographical part of Hungary. A Francisella tularensis culture collection was created. Phenotypic and genotypic features of F. tularensis isolates were characterized. Antibiotic susceptibility, metabolic fingerprinting and filogenetic evaluation of isolates were carried out. Epidemiological role of wild hare and hamster population were evaluated using serological methods and macroscopic and histopathology of tularemia were characterized in these two animal species

Carbon source utilisation and evaluation of the Biolog system in the identification of Actinobacillus pleuropneumoniae

Sixty-eight Actinobacillus pleuropneumoniae strains were isolated from porcine acute pleuropneumonia cases from different parts of Hungary between 2000 and 2014. A total of 41 isolates were identified as A. pleuropneumoniae bio-type I and 27 strains as biotype II based on cultural, morphological and biochemical characteristics. The aim of this study was to evaluate metabolic fingerprinting in the species-level identification of A. pleuropneumoniae isolates. Utilisation of carbon sources by these field isolates and six reference strains was characterised by the Biolog system (GN2 Microplate, MicroLog3 Version 4.20.05 software). Twenty-nine field strains were correctly identified by the Biolog system as A. pleuropneumoniae, 36 strains as A. lignieresii, two strains as H. paraphrohaemolyticus and one strain as A. equuli after 24 h of incubation. Among the six A. pleuropneumoniae reference strains the Biolog system identified one strain as A. pleuropneumoniae, four as A. lignieresii and one as H. paraphrohaemolyticus. There was no correlation between biotypes and serotypes of A. pleuropneumoniae and the carbon source utilisation pattern and species identification by the Biolog system. our data indicate that the efficacy of the Biolog system used here could be improved by including phenotypes of more A. pleuropneumoniae strains representing a wider geographical occurrence into the database

Identification of a proposed new serovar of Actinobacillus Pleuropneumoniae: Serovar 16

Five Actinobacillus pleuropneumoniae strains isolated from pathological lesions of porcine pleuropneumonia in Hungary could not be assigned to any of the accepted 15 serovars. Using hyperimmune serum raised against these unty-pable-serovar A. pleuropneumoniae strains in rabbits, indirect haemagglutination tests proved that they form a distinct group and there is no cross-reaction between them and the type strains of A. pleuropneumoniae. All five strains harboured the toxin-associated genes for the production (apxIA) and secretion (apxIB) of ApxI, the gene for the expression of ApxII and the largest-size (2800 bp) apxIV gene. The carbon source utilisation pattern and the sequence analysis of the 16S rRNA gene confirmed the species identification of the suggested type strain, A. pleuropneumoniae A-85/14. A new serovar of A. pleuropneumoniae — serovar 16 — is proposed with A. pleuropneumoniae A-85/14 as reference strain

Actinobacillus pleuropneumoniae serotypes in Hungary

A total of 255 Actinobacillus pleuropneumoniae isolates were collected from 634 lung samples representing 70 swine herds in Hungary between January 2012 and June 2016. On the basis of the indirect haemagglutination test 77 independent strains were included in the evaluation after the elimination of duplicate or multiple serotypes from the same herd. In the case of 7 herds strains of two different serotypes were identified. Fourteen Hungarian A. pleuropneumoniae isolates from the culture collection of the Department of Microbiology and Infectious Diseases, isolated before 2012, were also included in the evaluation (one each from 12 herds and two each from two herds, where two serotypes occurred). Out of the altogether 91 A. pleuropneumoniae strains 72 strains belonged to biotype I and 19 strains could be allocated to biotype II. In Hungary, the most common serotypes were serotype 2 (39.5%), 13 (15.4%), 8 (8.8%) and 16 (8.8%), but serotypes 9 (5.5%), 11 (3.3%) and 12 (3.3%) were also isolated. Twelve strains (13.2%) were untypable

Comparative analysis of Pasteurella multocida strains isolated from bovine respiratory infections

Bovine respiratory disease (BRD) is the leading cause of significant economic losses in the intensive beef industry worldwide. Beside numerous risk factors Pasteurella multocida, which is regarded as a secondary pathogen, may play a role in the development of the disease. Previous studies of strainsfrom swine pneumonia revealed that there are a few clones associated with clinical disease, suggesting that some strains may be more virulent than others. This linkage may be true in the BRD, however composition of P. multocida populations in the herds are slightly characterized. Thus, we decided to perform phenotypic and genotypic characterisation of strains isolated from calves with respiratory infection at 31 different herds in Hungary. The results demonstrated the presence of two dominant strain types. At the identical taxonomic background (P. multocida subsp. multocida) with slight phenotypic variability they could be separated by trehalose fermentation capacity, α-glucosidase activity and molecular fingerprint patterns of ERIC- and M13-PCR. Independent prevalence and geographical origin of the strain types may refer to their significance in the illness, but their comparison with strains isolated from healthy individuals is taken into consideration

A Pasteurellaceae család egyes emlőspatogén fajainak összehasonlító vizsgálata = Comparative examination of some mammal pathogens of the Family Pasteurellaceae

A Mannheimia haemolytica, a Histophilus somni és az Actinobacillus pleuropneumoniae az összehasonlító vizsgálatát végeztük el szénforrás-hasznosításon alapuló anyagcsere-ujjlenyomat meghatározása és pulzáló mezejű gélelektroforézis (PFGE) segítségével. Összesen 100 H. somni, 56 M. haemolytica és 73 A. pleuropneumoniae törzs szénforrás-hasznosítását vizsgáltuk. Valamennyi H. somni törzs hasznosítani tudott 2, M. haemolytica 5 és A. pleuropneumoniae törzs 20 szénforrást, míg a törzsek legalább 90%-a felhasznált további 5, 13 illetve 11 szénforrást. Ennek alapján a különböző állatfajokból és kórformákból származó H. somni törzseket meg lehetett különböztetni, míg a M. haemolytica és az A. pleuropneumoniae törzsek egységesebbek voltak. A PFGE vizsgálatok során a különböző állatfajból származó H. somni törzsek jól elkülönültek egymástól. A genitális kommenzális törzsek nagyobb genetikai diverzitást mutattak, mint az invazív fertőzésből izolált törzsek. Az A. pleuropneumoniae 2-es biocsoporton belül a genetikai különbség sokkal kisebb volt, mint az 1-es biocsoportba tartozó törzsek között. Az 1-es biotípuson belül 7 genetikai csoportot különböztettünk meg. Ezekbe a csoportokba általában egyazon szerotípusba sorolható törzsek tartoztak. A M. haemolytica a különböző szerotípusba tartozó izolátumai általában elkülönültek. A PFGE módszer alkalmas az egyazon szerotípusba tartozó törzsek megkülönböztetésére. Egy állományon belül a genetikai diverzitás nem jellemző a M. haemolytica-ra. | Comparative examination of three species of veterinary importance of the Family Pasteurellaceae, Mannheimia haemolytica, Histophilus somni and Actinobacillus pleuropneumonia was carried out using a metabolic fingerprinting method based on carbon source utilisation and pulsed field gel electrophoresis (PFGE). Carbon source utilisation of 100 H. somni, 56 M. haemolytica and 73 A. pleuropneumoniae strains was examined. All H. somni strains could utilise 2, M. haemolytica 5 and A. pleuropneumoniae strains 20 carbon sources, while further 5, 13 and 11 carbon sources respectively were metabolised by at least 90% of the strains. H. somni strains from different species and diseases could be differentiated on the basis of metabolic fingerprinting, while M. haemolytica and A. pleuropneumoniae strains proved to be more uniform. The H. somni strains isolated from different species could be differentiated using PFGE. Higher genetic diversity was evident among commensals of the genitals than among strains isolated from invasive diseases. The genetic differences within biotype 2 of A. pleuropneumoniae was much lower than biotype 1. Seven genetic groups could be differentiated within biotype 1 of A. pleuropneumoniae. The same serotypes belonged to the same genetic group. Serotypes of M. haemolytica formed different clusters, differentiation of the strains within the same serotype could be done with PFGE. The genetic diversity of M. haemolytica within a herd was not common

Comparative molecular characterization of Corynebacterium pseudotuberculosis strains isolated from Hungarian sheep and goat flocks

The genus Corynebacterium belongs to the order Actinomycetales that also includes the genera Mycobacterium, Nocardia, Streptomyces. Although this group is very heterogeneous, most of the species share particular characteristics, such as the cell wall composition and the high G+C ratio of the genomes. C. pseudotuberculosis is a Gram-positive, club-shaped rod, facultative intracellular bacteria that is commonly found in the environment as well as on the skin and mucous surfaces of animals. Based on biochemical features, the strains are classified into two biovars (ovis and equi). The strains within the biovar ovis presented negative nitrate reduction and mainly affect sheep and goats, causing caseous lymphadenitis (CL). The strains biovar equi reduce nitrate and cause ulcerative lymphangitis of the distal extremities, ventral abscesses of the thorax and abdomen, and furunculosis in horses. Occasionally, both types could generate subcutaneous abscesses or visceral organs in cattle. In addition, in rare instances, other domestic or wild animal species, and even human are affected. Due to the sale restrictions of pedigree sires, the reduction of milk, meat and woollen yields, expressive losses in reproductive efficiency, and condemnation of carcasses in slaughterhouse the caseous lymphadenitis causes significant economic losses to sheep producers worldwide. While the illness is common on the tropical areas, it occurs only sporadically in the Mediterraneum. In default of the appropriate import regulations it has spread throughout the world by the pedigree sires. The aim of our study was to molecular comparison of phenotypically characterized C. pseudotuberculosis strains have been collected form sheep and goat flocks in different areas of the country over the past twenty years (1994-2014). We opted for the multilocus sequence typing (MLST) analysis. In the absence of data from literature, we were going to use the MLST had been developed for the analysis of human pathogenic C. diphtheriae strains recently (2010). However the applied primers were C. diphtheriae specific, the developing of own system was needed. For designing of appropriate primers, we have collected and compare of sequences of 16 commonly applied housekeeping using whole genomes of C. pseudotuberculosis at the Genebank. During the examination of the individual genes, the C. pseudotuberculosis and C. diphtheriae strains proved to be distinct in any case and two biovars were found to various in some measure. Finally, the 600-800 bp long regions covering utmost single-nucleotide polymorphism (SNP) between the biovars and present identical phylogenetic topology of the entire genes of dnaK, odhA, the groL1 and infB were examined in detail. Although each of our strains were classified to C. pseudotuberculosis biovar ovis, the MLST examination demonstrated that the two biovars are separated at the level of the individual housekeeping genes. In light of the results is thought-provoking that the strains belong to ovis and the equi biovars represent the same taxonomic group despite the differences of genetic and phenotypic properties (nitrate reduction), of host spectrum (sheep, goat; horse) and of the manifestation of induced disease

Antimicrobial susceptibility of Bacillus anthracis strains from Hungary

The susceptibility of 29 Bacillus anthracis strains, collected in Hungary between 1933 and 2014, was tested to 10 antibiotics with commercially available minimum inhibitory concentration (MIC) test strips. All strains were susceptible to amoxicillin, ciprofloxacin, clindamycin, doxycycline, gentamicin, penicillin, rifampicin, and vancomycin. Intermediate susceptibility to erythromycin and cefotaxime was detected in 17.2% (5/29) and 58.6% (17/29) of the strains, respectively. Correlations were not observed between the isolation date, location, host species, genotype, and antibiotic susceptibility profile of strains

Screening of Hungarian cattle herds for seropositivity to Mycoplasma bovis

A total of 860 serum samples collected at 86 cattle farms in different parts of Hungary were screened for the presence of antibodies to Mycoplasma bovis using an ELISA test with a recombinant M. bovis membrane protein as antigen. Antibodies to M. bovis were detected in sera collected on all farms, and no farms negative for M. bovis were found. In 88.38% of the herds more than 50% of the sampled animals were infected by M. bovis. A total of 82.91% of the animals had antibodies to M. bovis. The proportion of seropositive animals was higher in the older age groups, and a significant difference was seen in the level of seropositivity between young and older age groups. The results show that M. bovis infection is widespread on Hungarian dairy farms, and its prevalence has increased in the recent decade. The high infection rate of Hungarian cattle herds with M. bovis shows that special attention should be paid to evaluating the aetiological role of M. bovis in bovine respiratory disease complex (BRDC) cases because M. bovis has an immunosuppressive effect and can predispose cattle to other respiratory infections, too

Characterisation of a multiresistant Pasteurella multocida strain isolated from cattle

The emergence of simultaneous resistance to multiple classes of antibiotics presents an increasing threat. Plasmid-borne multiresistance and integrative conjugative elements have been reported in Pasteurella multocida. We report an alternative strategy for the development of multiresistance observed in a P. multocida strain (Pm238) isolated from calf pneumonia. We identified genes integrated into the chromosomal DNA without known integrative and conjugative elements. These genes conferred resistance to streptomycin (strA), tetracycline (tetB), chloramphenicol (catAIII), and sulphonamides (sulII). We also detected mutation in the quinolone-resistance-determining regions of parC. No plasmids could be isolated from strain Pm238. These results suggest that P. multocida can accumulate multiple resistance determinants on the chromosome as single genes