Bordetella bronchiseptica produced pneumonia was studied in young piglets. At the beginning of th... more Bordetella bronchiseptica produced pneumonia was studied in young piglets. At the beginning of the experiment, 30 artifi cially reared 3-day-old piglets were divided into two groups: group A – uninfected piglets, control group (n=10) and group B – piglets infected with B bronchiseptica, experimental group (n=20). Th e B. bronchiseptica in-fection (10 6 CFU/ml) was performed on day 4. In Group B, clinical signs including mild serous nasal discharge, sneezing, panting, and hoarseness appeared from day 4. Computed tomography (CT) performed on day 16 demonstrated lung lesions attrib-utable to colonisation by B. bronchiseptica in the infected pigs. Th e gross pathological fi ndings confi rmed the results obtained by CT.
A more complicated pathology was observed in female pigs infected with Mycoplasma hyopneumoniae, ... more A more complicated pathology was observed in female pigs infected with Mycoplasma hyopneumoniae, when the same were exposed to 20 ppm dietary levels of fumonisin B1 (FB1) starting 14 days before infection for a period of 42 days as was assessed by gross pathology and pathomorphological examinations or computed tomography, and also manifested by the strong deterioration of the pneumonic process in two pigs and the subsequent euthanizing of one pig. Typical damages in FB1-fed pigs were a strong oedema in the lung and slight oedema in the other internal organs and mild degenerative changes in the kidneys, whereas the typical pathomorphological changes in M. hyopneumoniae-infected pigs corresponded to the morphologic pattern of a catarrhal bronchointerstitial pneumonia more pronounced in the cranial and middle lobes or in the cranial third of the caudal lobe of the lung. The pigs treated by both pathogens (toxic and infectious) revealed strong oedematous changes in the interstitium of l...
Mycoplasma hyopneumoniae has a primary role in the porcine respiratory disease complex (PRDC). Th... more Mycoplasma hyopneumoniae has a primary role in the porcine respiratory disease complex (PRDC). The objective of this study was to determine whether fumonisin mycotoxins influence the character and/or the severity of pathological processes induced in the lungs of pigs by Mycoplasma hyopneumoniae. Four groups of pigs (n = 7/group) were used, one fed 20 ppm fumonisin B1 (FB1) from 16 days of age (group F), one only infected with M. hyopneumoniae on study day 30 (group M), and a group fed FB1 and infected with M. hyopneumoniae (group MF), along with an untreated control group (group C). Computed tomography (CT) scans of infected pigs (M and MF) on study day 44 demonstrated lesions extending to the cranial and middle or in the cranial third of the caudal lobe of the lungs. The CT images obtained on study day 58 showed similar but milder lesions in 5 animals from group M, whereas lungs from 2 pigs in group MF appeared progressively worse. The evolution of average pulmonary density calcula...
Canadian journal of veterinary research = Revue canadienne de recherche vétérinaire, 2011
The interaction of Bordetella bronchiseptica, toxigenic Pasteurella multocida serotype D, and the... more The interaction of Bordetella bronchiseptica, toxigenic Pasteurella multocida serotype D, and the mycotoxin fumonisin B(1) (FB(1)) was studied. On day 0 of the experiment, 28 artificially reared 3-day-old piglets were divided into 4 groups (n = 7 each): a control group (A), a group fed FB(1) toxin (B), a group infected with the 2 pathogens (C), and a group infected with the 2 pathogens and fed FB(1) toxin (D). The B. bronchiseptica infection [with 10(6) colony-forming units (CFU)/mL] was performed on day 4 and the P. multocida infection (with 10(8) CFU/mL) on day 16. From day 16 a Fusarium verticillioides fungal culture (dietary FB(1) toxin content 10 mg/kg) was mixed into the feed of groups B and D. In groups C and D, clinical signs including mild serous nasal discharge, sneezing, panting, and hoarseness appeared from day 4, and then from day 16 some piglets had coughing and dyspnea as well. Computed tomography (CT) performed on day 16 demonstrated lung lesions attributable to colo...
Background: Mycoplasma bovis is a worldwide pathogen, causative agent of pneumonia, mastitis, art... more Background: Mycoplasma bovis is a worldwide pathogen, causative agent of pneumonia, mastitis, arthritis, and a variety of other symptoms in cattle. The economic losses due to mycoplasma pneumonia could be reduced by antibiotic treatment. The aim of the present study was to determine the in vitro susceptibility of M. bovis strains isolated from cattle in Hungary to eleven antibiotics.
Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spr... more Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spread in cattle. This study investigated the ability of modified live BVDV I and II components of a commercially available modified live virus (MLV) vaccine (Breed-Back FP 10, Boehringer Ingelheim Vetmedica Inc.) to prevent fetal infection and abortion, and therefore the birth of persistently infected animals. Heifers immunized with vaccine 4-8 weeks before insemination showed no adverse effects. All vaccinated animals had seroconverted to BVDV 4 weeks after immunization. Pregnant heifers were divided into two vaccination and two control groups and challenged with type I or II BVDV on days 60-90 of gestation. Seroconversion, clinical signs, immunosuppression, viremia, mortality, abortion rate, and fetal infection were studied. Post-challenge, 6/11 (type I challenged) and 8/11 (type II challenged) vaccinated heifers were free from clinical signs of BVD. Post-challenge clinical signs noted i...
Bordetella bronchiseptica is a widespread Gram-negative pathogen occurring in different mammal sp... more Bordetella bronchiseptica is a widespread Gram-negative pathogen occurring in different mammal species. It is known to play a role in the aetiology of infectious atrophic rhinitis of swine, canine kennel cough, respiratory syndromes of cats, rabbits and guinea pigs, and sporadic human cases have also been reported. In this study, 93 B. bronchiseptica strains were examined from a broad range of host species and different geographical regions using restriction fragment length polymorphism analysis of polymerase chain reaction products of flaA to reveal the possible host-specificity of the flagellin. Eight types (A-H) of flaA were identified, including five newly described ones (D-H). All but one of the 22 B. bronchiseptica strains from swine showed type B fragment pattern. The eighteen Hungarian isolates of canine origin were uniform (type A) while in other countries type B and D were also present in dogs. The sequence and phylogenetic analysis of 36 representative strains of flaA types revealed four clusters. These clusters correlated with flaA PCR-RFLP types and host species, especially in pigs and dogs. The revealed diversity of the strains isolated from human cases indicated possible zoonotic transmissions from various animal sources.
Bordetella bronchiseptica is a widespread pathogen, with a broad host range, occasionally includi... more Bordetella bronchiseptica is a widespread pathogen, with a broad host range, occasionally including humans. Diverse virulence factors (adhesins, toxins) allow its adaptation to its host, but this property of the adenylate cyclase (cyaA) toxin is not well understood. In this study, we analyzed the repeats-in-toxin domain of B. bronchiseptica cyaA with PCR, followed by restriction fragment length analysis. Of ninety-two B. bronchiseptica strains collected from different hosts and geographic regions, 72 (78.3 %) carried cyaA and four RFLP types (A-D) were established using NarI and SalI. However, in 20 strains, cyaA was replaced with a peptide transport protein operon. A phylogenetic tree based on partial nucleotide sequences of cyaA revealed that group 2 contains strains of specifically human origin, whereas subgroup 1a contains all but one of the strains from pigs. The human strains showed many PCR-RFLP and sequence variants, confirming the clonal population structure of B. bronchiseptica.
Phenotypic and genotypic diversity of forty-two Pasteurella multocida isolates from geese were ch... more Phenotypic and genotypic diversity of forty-two Pasteurella multocida isolates from geese were characterized by analysis of their capsular type, Heddleston serotype, biotype, fimbrial gene allele type, comparative outer membrane protein (OMP) electrophoresis patterns, and were analyzed using PCR for the presence of virulence-associated genes (toxA, tbpA, pfhA, hgbA, hgbB, nanH, nanB, fimA, hsf-1, and pmHAS). A sequence comparison of the thdF and rpoB housekeeping genes of twenty representative P. multocida strains from three different OMP groups demonstrated that seventeen strains were closely related phylogenetically to previously published strains of P. multocida subsp. multocida and P. multocida subsp. gallicida, and only three strains from geese were grouped with previously published strains of P. multocida subsp. septica. This study is the first report regarding the characterization of phenotypic and genotypic features of different P. multocida field strains isolated from geese with the different clinical representation of pasteurellosis and provide our overview on the usefulness of these in vitro tests for primary characterization of P. multocida strains for the epidemiological studies of fowl cholera.
Several new taxa belonging to the genus Francisella have been described recently. The present stu... more Several new taxa belonging to the genus Francisella have been described recently. The present study describes the prevalence of Francisella tularensis and Francisella-like endosymbionts (FLE) in ticks collected from Hungary from 2007 to 2009 and characterizes the genetic variability of FLEs. A total of 5402 Ixodid ticks (Ixodes ricinus, I. acuminatus, Dermacentor marginatus, D. reticulatus, Haemaphysalis inermis, H. concinna, H. punctata) were collected from vegetation and animal hosts and tested with conventional PCR, detecting the 16S rRNA and tul4 genes. F. tularensis ssp. holarctica was found in 2 pools of H. concinna and 1 pool of D. reticulatus, both representing minimum prevalence (calculated with 1 infected tick per pool) of 0.27% whereas the sequences of a FLE were detected in 11 pools of D. reticulatus showing a minimum prevalence of 3%. Although the tul4 gene sequence of this FLE was identical to all Hungarian and Portuguese FLEs found earlier, and the 16S rRNA sequence was also identical to the sequence of the endosymbiont of D. reticulatus described in Bulgaria, these 16S rRNA gene coding sequences differed in 2 nucleotides from the one found earlier in this tick species in Hungary. This divergence may appear to be a minor difference between the sequences, potentially even resulting from a technical failure, but it could also indicate a significant difference stemming from the conservative genetic character of Francisellaceae. Thus, it raises a question about the number of FLE variants circulating in D. reticulatus in Europe and indicates the need for further data about the FLEs described in other parts of the continent and new FLE genotyping markers.
Q fever is an important zoonotic disease caused by Coxiella burnetii. There are few reliable data... more Q fever is an important zoonotic disease caused by Coxiella burnetii. There are few reliable data about C. burnetii infection available. The aim of this study was to assess the importance and potential infectious sources of Q fever in Hungary. A total of 215 milk samples (10 individual samples from each herd and 1 bulk tank milk sample from each cattle herd), and 400 serum samples (20 from each herd) were tested from 15 dairy cattle herds and 5 sheep flocks located in different parts of Hungary. The study found 19.3% (58/300) and 38.0% (57/150) seropositivity in cattle, and 0% (0/100) and 6.0% (3/50) seropositivity in sheep, by complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA), respectively. C. burnetii DNA was detected by IS1111 element-based TaqMan real-time polymerase chain reaction (PCR) in 8.7% (13/150) of individual dairy cow milk samples, 4.0% (2/50) of individual sheep milk samples, and 66.7% (10/15) of dairy bulk tank milk samples. Samples taken from nine different commercially-available pasteurized cow milk products from different Hungarian producers were also tested for the presence of C. burnetii DNA, and eight of these samples were found to be positive (88.9%). The real-time PCR examination of 5402 ixodid ticks collected from different parts of the country yielded negative results. Knowledge of the true prevalence of Q fever is crucial for policymakers involved in evidence-based decision making.
We compared three challenge models for the assessment of atrophic rhinitis (AR) vaccines: combine... more We compared three challenge models for the assessment of atrophic rhinitis (AR) vaccines: combined infection with Bordetella bronchiseptica (Bb) and Pasteurella multocida (Pm); application of acetic acid (AA) to the nasal mucosa followed by Pm infection; and Bb infection alone. Two vaccines were tested using standardized criteria, notably nasal lesion scores. The vaccines provided different levels of protection in the Bb and the AA/Pm challenges, but were similar in the combined (Bb/Pm) challenge. It is clear that the AA/Pm model shows the protective value of only the Pm component, whereas the single Bb challenge reflects the protective value merely of the Bb component of a combined vaccine. These results suggest that the best assessment of protection is provided if the two specific challenges are performed separately.
Journal of Veterinary Diagnostic Investigation, 2010
Pasteurella multocida is the causative agent of fowl cholera in domesticated and wild birds. The ... more Pasteurella multocida is the causative agent of fowl cholera in domesticated and wild birds. The disease outcome is affected by various host-and pathogen-specific determinants. Several putative virulence factors have been proposed to play a key role in this interaction, including the ptfA gene, the products of which assemble to form type 4 fimbriae on the bacterial surface. One way to understand more precisely how ptfA contributes to pathogenesis is to gather molecular features of this gene in circulating avian P. multocida strains. Therefore, molecular characterization of the ptfA gene of P. multocida strains isolated from domestic poultry was performed using the combination of nucleotide sequence analysis and a newly developed allelespecific polymerase chain reaction assay. Two major ptfA alleles were identified among 31 strains, representing various serogroups and somatic serotypes. It was noteworthy that allele specificity and case severity of a subset of strains correlated with the available gross pathology data. Therefore, the acquisition of comprehensive clinical and epidemiological data together with molecular characteristics of individual strains will help to design and implement adequate preventive and intervention strategies.
Determining the in vitro susceptibility to 11 antibiotics of Francisella tularensis subsp. holarc... more Determining the in vitro susceptibility to 11 antibiotics of Francisella tularensis subsp. holarctica strains belonging to the phylogenetic group B.13, from different areas of Hungary. Twenty-nine F. tularensis strains isolated between 2003 and 2010 from free-ranging European brown hares (Lepus europaeus) and a captive patas monkey (Erythrocebus patas) were collected from different parts of Hungary and examined for antibiotic susceptibility with commercially available MIC test strips on modified Francis agar plates; values were interpreted according to CLSI breakpoints. The strains were susceptible to aminoglycosides (MIC(90) values: gentamicin, 0.75 mg/L; and streptomycin, 6.0 mg/L), tetracyclines (MIC(90) values: tetracycline, 0.5 mg/L; and doxycycline, 1.0 mg/L), quinolones (MIC(90) values: ciprofloxacin, 0.047 mg/L; and levofloxacin, 0.023 mg/L) and chloramphenicol (MIC(90) value: 1.5 mg/L), i.e. antibiotics commonly used in therapy. Tigecycline (MIC(90) value: 0.19 mg/L) and rifampicin (MIC(90) value: 1.0 mg/L) were also active against F. tularensis strains, while resistance to erythromycin (MIC(90) value: >256 mg/L) and linezolid (MIC(90) value: 32 mg/L) was observed in all strains. Based on the results, quinolones are recommended as first choice therapy for F. tularensis infection. The in vitro susceptibility of the strains to tigecycline may encourage the application of this antibiotic as well. The similar antibiotic susceptibilities of the Hungarian strains belonging to different subclades of phylogenetic group B.13 indicates that strains from other Central and Eastern European countries belonging to this group might also have the same susceptibility profile.
Page 1. 172 CommuniCation Effect of Mycoplasma hyopneumoniae and fumonisin B 1 toxin on the lung ... more Page 1. 172 CommuniCation Effect of Mycoplasma hyopneumoniae and fumonisin B 1 toxin on the lung in pigs Roland Pósa1, Melinda Kovács1, Tamás Donkó2, Judit Szabó-Fodor1, József Mondok1, Péter Bogner2, Imre Repa2, Tibor Magyar3 ...
International Journal of Medical Microbiology, 2010
Neonatal infections may be caused by various microorganisms, but as far as we are aware, Acinetob... more Neonatal infections may be caused by various microorganisms, but as far as we are aware, Acinetobacter ursingii has not yet been reported in connection with nosocomial infections of premature infants. During 2 months, 3 premature babies were treated with nosocomial infection caused by A. ursingii at the same ward, and on the basis of molecular typing results the same strain was responsible for all of these cases. Traditional biochemical methods and automatic identification systems failed to identify this bacterium on the species level, and only 16S rDNA sequencing gave acceptable species identifications. The isolated strains proved to be susceptible to all of the tested antimicrobials, including ampicillin/sulbactam, doxycyclin, netilmicin, ciprofloxacin, piperacillin/tazobactam, ceftazidime, imipenem, meropenem, trimethoprim/sulfametoxazole, gentamicin, tobramycin, amikacin, and levofloxacin according to the CLSI standard. In spite of the environmental screening, the source of the infection could not be clarified. One of 3 neonates died, the others recovered and were discharged home after several months of hospitalization.
Diagnostic microbiology and infectious disease, 2011
The zoonotic impact of Pasteurella species in human wounds caused by cats and dogs has increased ... more The zoonotic impact of Pasteurella species in human wounds caused by cats and dogs has increased recently. In this study, the effectiveness of the Biolog Microstation ID System (Biolog, Hayward, CA) for the identification of certain species of Pasteurella sensu stricto was analysed. Thirty-eight isolates originating from dogs and cats were studied by pheno-and genotypic methods. The classical biochemical tests identified these isolates as P. multocida, P. dagmatis, and P. canis, while the Biolog system distinguished only 2 categories: P. multocida and P. dagmatis. The sodA gene sequence-based phylogenetic analysis revealed that the isolates identified as P. dagmatis by the Biolog system were either P. dagmatis, P. canis, or P. dagmatis-like genomospecies. The low discrimination power of the Biolog system in the case of these closely related Pasteurella species draws attention to the need of continuously improving the database of automated microbial identification systems.
Background: Atrophic rhinitis is a widely prevalent infectious disease of swine caused by Bordete... more Background: Atrophic rhinitis is a widely prevalent infectious disease of swine caused by Bordetella bronchiseptica and Pasteurella multocida. The course of the disease is considered to be different depending on the principal aetiological agents distinguishing B. bronchiseptica induced non-progressive and toxigenic P. multocida produced progressive forms. In order to compare the pathological events of the two forms of the disease, the development of nasal lesions has longitudinally been studied in pigs infected by either B. bronchiseptica alone or B. bronchiseptica and toxigenic P. multocida together using computed tomography to visualise the nasal structures. Results: B. bronchiseptica infection alone caused moderately severe nasal turbinate atrophy and these lesions completely regenerated by the time of slaughter. Unexpectedly, complete regeneration of the bony structures of the nasal cavity was also observed in pigs infected by B. bronchiseptica and toxigenic P. multocida together in spite of seeing severe turbinate atrophy in most of the infected animals around the age of six weeks.
Four urease-negative Bordetella bronchiseptica isolates originating from pigs were examined by ph... more Four urease-negative Bordetella bronchiseptica isolates originating from pigs were examined by phenotypic and molecular methods. The phenotypic properties of the isolates were in harmony with the data of the literature, except for the lack of urease activity in conventional tube test, API 20 NE and Diatabs™ assays. Using genotypic methods, the urease-negative isolates did not differ from the urease-positive reference strain. They were positive in species-specific and ureC PCR, and all strains showed uniform bands in PCR-RFLP studies of flaA genes. The reason for the lack of urease activity, a characteristic considered species specific for B. bronchiseptica, needs to be studied further. The finding underlines the significance of genotyping when the phenotypic identification of B. bronchiseptica seems questionable.
Bordetella bronchiseptica produced pneumonia was studied in young piglets. At the beginning of th... more Bordetella bronchiseptica produced pneumonia was studied in young piglets. At the beginning of the experiment, 30 artifi cially reared 3-day-old piglets were divided into two groups: group A – uninfected piglets, control group (n=10) and group B – piglets infected with B bronchiseptica, experimental group (n=20). Th e B. bronchiseptica in-fection (10 6 CFU/ml) was performed on day 4. In Group B, clinical signs including mild serous nasal discharge, sneezing, panting, and hoarseness appeared from day 4. Computed tomography (CT) performed on day 16 demonstrated lung lesions attrib-utable to colonisation by B. bronchiseptica in the infected pigs. Th e gross pathological fi ndings confi rmed the results obtained by CT.
A more complicated pathology was observed in female pigs infected with Mycoplasma hyopneumoniae, ... more A more complicated pathology was observed in female pigs infected with Mycoplasma hyopneumoniae, when the same were exposed to 20 ppm dietary levels of fumonisin B1 (FB1) starting 14 days before infection for a period of 42 days as was assessed by gross pathology and pathomorphological examinations or computed tomography, and also manifested by the strong deterioration of the pneumonic process in two pigs and the subsequent euthanizing of one pig. Typical damages in FB1-fed pigs were a strong oedema in the lung and slight oedema in the other internal organs and mild degenerative changes in the kidneys, whereas the typical pathomorphological changes in M. hyopneumoniae-infected pigs corresponded to the morphologic pattern of a catarrhal bronchointerstitial pneumonia more pronounced in the cranial and middle lobes or in the cranial third of the caudal lobe of the lung. The pigs treated by both pathogens (toxic and infectious) revealed strong oedematous changes in the interstitium of l...
Mycoplasma hyopneumoniae has a primary role in the porcine respiratory disease complex (PRDC). Th... more Mycoplasma hyopneumoniae has a primary role in the porcine respiratory disease complex (PRDC). The objective of this study was to determine whether fumonisin mycotoxins influence the character and/or the severity of pathological processes induced in the lungs of pigs by Mycoplasma hyopneumoniae. Four groups of pigs (n = 7/group) were used, one fed 20 ppm fumonisin B1 (FB1) from 16 days of age (group F), one only infected with M. hyopneumoniae on study day 30 (group M), and a group fed FB1 and infected with M. hyopneumoniae (group MF), along with an untreated control group (group C). Computed tomography (CT) scans of infected pigs (M and MF) on study day 44 demonstrated lesions extending to the cranial and middle or in the cranial third of the caudal lobe of the lungs. The CT images obtained on study day 58 showed similar but milder lesions in 5 animals from group M, whereas lungs from 2 pigs in group MF appeared progressively worse. The evolution of average pulmonary density calcula...
Canadian journal of veterinary research = Revue canadienne de recherche vétérinaire, 2011
The interaction of Bordetella bronchiseptica, toxigenic Pasteurella multocida serotype D, and the... more The interaction of Bordetella bronchiseptica, toxigenic Pasteurella multocida serotype D, and the mycotoxin fumonisin B(1) (FB(1)) was studied. On day 0 of the experiment, 28 artificially reared 3-day-old piglets were divided into 4 groups (n = 7 each): a control group (A), a group fed FB(1) toxin (B), a group infected with the 2 pathogens (C), and a group infected with the 2 pathogens and fed FB(1) toxin (D). The B. bronchiseptica infection [with 10(6) colony-forming units (CFU)/mL] was performed on day 4 and the P. multocida infection (with 10(8) CFU/mL) on day 16. From day 16 a Fusarium verticillioides fungal culture (dietary FB(1) toxin content 10 mg/kg) was mixed into the feed of groups B and D. In groups C and D, clinical signs including mild serous nasal discharge, sneezing, panting, and hoarseness appeared from day 4, and then from day 16 some piglets had coughing and dyspnea as well. Computed tomography (CT) performed on day 16 demonstrated lung lesions attributable to colo...
Background: Mycoplasma bovis is a worldwide pathogen, causative agent of pneumonia, mastitis, art... more Background: Mycoplasma bovis is a worldwide pathogen, causative agent of pneumonia, mastitis, arthritis, and a variety of other symptoms in cattle. The economic losses due to mycoplasma pneumonia could be reduced by antibiotic treatment. The aim of the present study was to determine the in vitro susceptibility of M. bovis strains isolated from cattle in Hungary to eleven antibiotics.
Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spr... more Fetal infection with bovine virus diarrhea virus (BVDV) causes severe economic loss and virus spread in cattle. This study investigated the ability of modified live BVDV I and II components of a commercially available modified live virus (MLV) vaccine (Breed-Back FP 10, Boehringer Ingelheim Vetmedica Inc.) to prevent fetal infection and abortion, and therefore the birth of persistently infected animals. Heifers immunized with vaccine 4-8 weeks before insemination showed no adverse effects. All vaccinated animals had seroconverted to BVDV 4 weeks after immunization. Pregnant heifers were divided into two vaccination and two control groups and challenged with type I or II BVDV on days 60-90 of gestation. Seroconversion, clinical signs, immunosuppression, viremia, mortality, abortion rate, and fetal infection were studied. Post-challenge, 6/11 (type I challenged) and 8/11 (type II challenged) vaccinated heifers were free from clinical signs of BVD. Post-challenge clinical signs noted i...
Bordetella bronchiseptica is a widespread Gram-negative pathogen occurring in different mammal sp... more Bordetella bronchiseptica is a widespread Gram-negative pathogen occurring in different mammal species. It is known to play a role in the aetiology of infectious atrophic rhinitis of swine, canine kennel cough, respiratory syndromes of cats, rabbits and guinea pigs, and sporadic human cases have also been reported. In this study, 93 B. bronchiseptica strains were examined from a broad range of host species and different geographical regions using restriction fragment length polymorphism analysis of polymerase chain reaction products of flaA to reveal the possible host-specificity of the flagellin. Eight types (A-H) of flaA were identified, including five newly described ones (D-H). All but one of the 22 B. bronchiseptica strains from swine showed type B fragment pattern. The eighteen Hungarian isolates of canine origin were uniform (type A) while in other countries type B and D were also present in dogs. The sequence and phylogenetic analysis of 36 representative strains of flaA types revealed four clusters. These clusters correlated with flaA PCR-RFLP types and host species, especially in pigs and dogs. The revealed diversity of the strains isolated from human cases indicated possible zoonotic transmissions from various animal sources.
Bordetella bronchiseptica is a widespread pathogen, with a broad host range, occasionally includi... more Bordetella bronchiseptica is a widespread pathogen, with a broad host range, occasionally including humans. Diverse virulence factors (adhesins, toxins) allow its adaptation to its host, but this property of the adenylate cyclase (cyaA) toxin is not well understood. In this study, we analyzed the repeats-in-toxin domain of B. bronchiseptica cyaA with PCR, followed by restriction fragment length analysis. Of ninety-two B. bronchiseptica strains collected from different hosts and geographic regions, 72 (78.3 %) carried cyaA and four RFLP types (A-D) were established using NarI and SalI. However, in 20 strains, cyaA was replaced with a peptide transport protein operon. A phylogenetic tree based on partial nucleotide sequences of cyaA revealed that group 2 contains strains of specifically human origin, whereas subgroup 1a contains all but one of the strains from pigs. The human strains showed many PCR-RFLP and sequence variants, confirming the clonal population structure of B. bronchiseptica.
Phenotypic and genotypic diversity of forty-two Pasteurella multocida isolates from geese were ch... more Phenotypic and genotypic diversity of forty-two Pasteurella multocida isolates from geese were characterized by analysis of their capsular type, Heddleston serotype, biotype, fimbrial gene allele type, comparative outer membrane protein (OMP) electrophoresis patterns, and were analyzed using PCR for the presence of virulence-associated genes (toxA, tbpA, pfhA, hgbA, hgbB, nanH, nanB, fimA, hsf-1, and pmHAS). A sequence comparison of the thdF and rpoB housekeeping genes of twenty representative P. multocida strains from three different OMP groups demonstrated that seventeen strains were closely related phylogenetically to previously published strains of P. multocida subsp. multocida and P. multocida subsp. gallicida, and only three strains from geese were grouped with previously published strains of P. multocida subsp. septica. This study is the first report regarding the characterization of phenotypic and genotypic features of different P. multocida field strains isolated from geese with the different clinical representation of pasteurellosis and provide our overview on the usefulness of these in vitro tests for primary characterization of P. multocida strains for the epidemiological studies of fowl cholera.
Several new taxa belonging to the genus Francisella have been described recently. The present stu... more Several new taxa belonging to the genus Francisella have been described recently. The present study describes the prevalence of Francisella tularensis and Francisella-like endosymbionts (FLE) in ticks collected from Hungary from 2007 to 2009 and characterizes the genetic variability of FLEs. A total of 5402 Ixodid ticks (Ixodes ricinus, I. acuminatus, Dermacentor marginatus, D. reticulatus, Haemaphysalis inermis, H. concinna, H. punctata) were collected from vegetation and animal hosts and tested with conventional PCR, detecting the 16S rRNA and tul4 genes. F. tularensis ssp. holarctica was found in 2 pools of H. concinna and 1 pool of D. reticulatus, both representing minimum prevalence (calculated with 1 infected tick per pool) of 0.27% whereas the sequences of a FLE were detected in 11 pools of D. reticulatus showing a minimum prevalence of 3%. Although the tul4 gene sequence of this FLE was identical to all Hungarian and Portuguese FLEs found earlier, and the 16S rRNA sequence was also identical to the sequence of the endosymbiont of D. reticulatus described in Bulgaria, these 16S rRNA gene coding sequences differed in 2 nucleotides from the one found earlier in this tick species in Hungary. This divergence may appear to be a minor difference between the sequences, potentially even resulting from a technical failure, but it could also indicate a significant difference stemming from the conservative genetic character of Francisellaceae. Thus, it raises a question about the number of FLE variants circulating in D. reticulatus in Europe and indicates the need for further data about the FLEs described in other parts of the continent and new FLE genotyping markers.
Q fever is an important zoonotic disease caused by Coxiella burnetii. There are few reliable data... more Q fever is an important zoonotic disease caused by Coxiella burnetii. There are few reliable data about C. burnetii infection available. The aim of this study was to assess the importance and potential infectious sources of Q fever in Hungary. A total of 215 milk samples (10 individual samples from each herd and 1 bulk tank milk sample from each cattle herd), and 400 serum samples (20 from each herd) were tested from 15 dairy cattle herds and 5 sheep flocks located in different parts of Hungary. The study found 19.3% (58/300) and 38.0% (57/150) seropositivity in cattle, and 0% (0/100) and 6.0% (3/50) seropositivity in sheep, by complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA), respectively. C. burnetii DNA was detected by IS1111 element-based TaqMan real-time polymerase chain reaction (PCR) in 8.7% (13/150) of individual dairy cow milk samples, 4.0% (2/50) of individual sheep milk samples, and 66.7% (10/15) of dairy bulk tank milk samples. Samples taken from nine different commercially-available pasteurized cow milk products from different Hungarian producers were also tested for the presence of C. burnetii DNA, and eight of these samples were found to be positive (88.9%). The real-time PCR examination of 5402 ixodid ticks collected from different parts of the country yielded negative results. Knowledge of the true prevalence of Q fever is crucial for policymakers involved in evidence-based decision making.
We compared three challenge models for the assessment of atrophic rhinitis (AR) vaccines: combine... more We compared three challenge models for the assessment of atrophic rhinitis (AR) vaccines: combined infection with Bordetella bronchiseptica (Bb) and Pasteurella multocida (Pm); application of acetic acid (AA) to the nasal mucosa followed by Pm infection; and Bb infection alone. Two vaccines were tested using standardized criteria, notably nasal lesion scores. The vaccines provided different levels of protection in the Bb and the AA/Pm challenges, but were similar in the combined (Bb/Pm) challenge. It is clear that the AA/Pm model shows the protective value of only the Pm component, whereas the single Bb challenge reflects the protective value merely of the Bb component of a combined vaccine. These results suggest that the best assessment of protection is provided if the two specific challenges are performed separately.
Journal of Veterinary Diagnostic Investigation, 2010
Pasteurella multocida is the causative agent of fowl cholera in domesticated and wild birds. The ... more Pasteurella multocida is the causative agent of fowl cholera in domesticated and wild birds. The disease outcome is affected by various host-and pathogen-specific determinants. Several putative virulence factors have been proposed to play a key role in this interaction, including the ptfA gene, the products of which assemble to form type 4 fimbriae on the bacterial surface. One way to understand more precisely how ptfA contributes to pathogenesis is to gather molecular features of this gene in circulating avian P. multocida strains. Therefore, molecular characterization of the ptfA gene of P. multocida strains isolated from domestic poultry was performed using the combination of nucleotide sequence analysis and a newly developed allelespecific polymerase chain reaction assay. Two major ptfA alleles were identified among 31 strains, representing various serogroups and somatic serotypes. It was noteworthy that allele specificity and case severity of a subset of strains correlated with the available gross pathology data. Therefore, the acquisition of comprehensive clinical and epidemiological data together with molecular characteristics of individual strains will help to design and implement adequate preventive and intervention strategies.
Determining the in vitro susceptibility to 11 antibiotics of Francisella tularensis subsp. holarc... more Determining the in vitro susceptibility to 11 antibiotics of Francisella tularensis subsp. holarctica strains belonging to the phylogenetic group B.13, from different areas of Hungary. Twenty-nine F. tularensis strains isolated between 2003 and 2010 from free-ranging European brown hares (Lepus europaeus) and a captive patas monkey (Erythrocebus patas) were collected from different parts of Hungary and examined for antibiotic susceptibility with commercially available MIC test strips on modified Francis agar plates; values were interpreted according to CLSI breakpoints. The strains were susceptible to aminoglycosides (MIC(90) values: gentamicin, 0.75 mg/L; and streptomycin, 6.0 mg/L), tetracyclines (MIC(90) values: tetracycline, 0.5 mg/L; and doxycycline, 1.0 mg/L), quinolones (MIC(90) values: ciprofloxacin, 0.047 mg/L; and levofloxacin, 0.023 mg/L) and chloramphenicol (MIC(90) value: 1.5 mg/L), i.e. antibiotics commonly used in therapy. Tigecycline (MIC(90) value: 0.19 mg/L) and rifampicin (MIC(90) value: 1.0 mg/L) were also active against F. tularensis strains, while resistance to erythromycin (MIC(90) value: >256 mg/L) and linezolid (MIC(90) value: 32 mg/L) was observed in all strains. Based on the results, quinolones are recommended as first choice therapy for F. tularensis infection. The in vitro susceptibility of the strains to tigecycline may encourage the application of this antibiotic as well. The similar antibiotic susceptibilities of the Hungarian strains belonging to different subclades of phylogenetic group B.13 indicates that strains from other Central and Eastern European countries belonging to this group might also have the same susceptibility profile.
Page 1. 172 CommuniCation Effect of Mycoplasma hyopneumoniae and fumonisin B 1 toxin on the lung ... more Page 1. 172 CommuniCation Effect of Mycoplasma hyopneumoniae and fumonisin B 1 toxin on the lung in pigs Roland Pósa1, Melinda Kovács1, Tamás Donkó2, Judit Szabó-Fodor1, József Mondok1, Péter Bogner2, Imre Repa2, Tibor Magyar3 ...
International Journal of Medical Microbiology, 2010
Neonatal infections may be caused by various microorganisms, but as far as we are aware, Acinetob... more Neonatal infections may be caused by various microorganisms, but as far as we are aware, Acinetobacter ursingii has not yet been reported in connection with nosocomial infections of premature infants. During 2 months, 3 premature babies were treated with nosocomial infection caused by A. ursingii at the same ward, and on the basis of molecular typing results the same strain was responsible for all of these cases. Traditional biochemical methods and automatic identification systems failed to identify this bacterium on the species level, and only 16S rDNA sequencing gave acceptable species identifications. The isolated strains proved to be susceptible to all of the tested antimicrobials, including ampicillin/sulbactam, doxycyclin, netilmicin, ciprofloxacin, piperacillin/tazobactam, ceftazidime, imipenem, meropenem, trimethoprim/sulfametoxazole, gentamicin, tobramycin, amikacin, and levofloxacin according to the CLSI standard. In spite of the environmental screening, the source of the infection could not be clarified. One of 3 neonates died, the others recovered and were discharged home after several months of hospitalization.
Diagnostic microbiology and infectious disease, 2011
The zoonotic impact of Pasteurella species in human wounds caused by cats and dogs has increased ... more The zoonotic impact of Pasteurella species in human wounds caused by cats and dogs has increased recently. In this study, the effectiveness of the Biolog Microstation ID System (Biolog, Hayward, CA) for the identification of certain species of Pasteurella sensu stricto was analysed. Thirty-eight isolates originating from dogs and cats were studied by pheno-and genotypic methods. The classical biochemical tests identified these isolates as P. multocida, P. dagmatis, and P. canis, while the Biolog system distinguished only 2 categories: P. multocida and P. dagmatis. The sodA gene sequence-based phylogenetic analysis revealed that the isolates identified as P. dagmatis by the Biolog system were either P. dagmatis, P. canis, or P. dagmatis-like genomospecies. The low discrimination power of the Biolog system in the case of these closely related Pasteurella species draws attention to the need of continuously improving the database of automated microbial identification systems.
Background: Atrophic rhinitis is a widely prevalent infectious disease of swine caused by Bordete... more Background: Atrophic rhinitis is a widely prevalent infectious disease of swine caused by Bordetella bronchiseptica and Pasteurella multocida. The course of the disease is considered to be different depending on the principal aetiological agents distinguishing B. bronchiseptica induced non-progressive and toxigenic P. multocida produced progressive forms. In order to compare the pathological events of the two forms of the disease, the development of nasal lesions has longitudinally been studied in pigs infected by either B. bronchiseptica alone or B. bronchiseptica and toxigenic P. multocida together using computed tomography to visualise the nasal structures. Results: B. bronchiseptica infection alone caused moderately severe nasal turbinate atrophy and these lesions completely regenerated by the time of slaughter. Unexpectedly, complete regeneration of the bony structures of the nasal cavity was also observed in pigs infected by B. bronchiseptica and toxigenic P. multocida together in spite of seeing severe turbinate atrophy in most of the infected animals around the age of six weeks.
Four urease-negative Bordetella bronchiseptica isolates originating from pigs were examined by ph... more Four urease-negative Bordetella bronchiseptica isolates originating from pigs were examined by phenotypic and molecular methods. The phenotypic properties of the isolates were in harmony with the data of the literature, except for the lack of urease activity in conventional tube test, API 20 NE and Diatabs™ assays. Using genotypic methods, the urease-negative isolates did not differ from the urease-positive reference strain. They were positive in species-specific and ureC PCR, and all strains showed uniform bands in PCR-RFLP studies of flaA genes. The reason for the lack of urease activity, a characteristic considered species specific for B. bronchiseptica, needs to be studied further. The finding underlines the significance of genotyping when the phenotypic identification of B. bronchiseptica seems questionable.
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