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Microbiology Spectrum Feb 2022Actinobacillus pleuropneumoniae causes porcine pleuropneumonia, an important disease in the pig industry. Accurate and sensitive diagnostics such as DNA-based...
Actinobacillus pleuropneumoniae causes porcine pleuropneumonia, an important disease in the pig industry. Accurate and sensitive diagnostics such as DNA-based diagnostics are essential for preventing or responding to an outbreak. The specificity of DNA-based diagnostics depends on species-specific markers. Previously, an insertion element was found within an A. pleuropneumoniae-specific gene commonly used for A. pleuropneumoniae detection, prompting the need for additional species-specific markers. Herein, 12 marker candidates highly conserved (99 - 100% identity) among 34 A. pleuropneumoniae genomes (covering 13 serovars) were identified to be A. pleuropneumoniae-specific , as these sequences are distinct from 30 genomes of 13 other and problematic [] species and more than 1700 genomes of other bacteria in the family. Five marker candidates are within the gene, a known A. pleuropneumoniae-specific gene, validating our marker discovery method. Seven other A. pleuropneumoniae-specific marker candidates within the , , , , and genes were validated by polymerase chain reaction (PCR) to be specific to 129 isolates of A. pleuropneumoniae (covering all 19 serovars), but not to four closely related species, four [] species, or seven other bacterial species. This is the first study to identify A. pleuropneumoniae-specific markers through genome mining. Seven novel A. pleuropneumoniae-specific DNA markers were identified by a combination of and molecular methods and can serve as additional or alternative targets for A. pleuropneumoniae diagnostics, potentially leading to better control of the disease. Species-specific markers are crucial for infectious disease diagnostics. Mutations within a marker sequence can lead to false-negative results, inappropriate treatment, and economic loss. The availability of several species-specific markers is therefore desirable. In this study, 12 DNA markers specific to A. pleuropneumoniae, a pig pathogen, were simultaneously identified. Five marker candidates are within a known A. pleuropneumoniae-specific gene. Seven novel markers can be used as additional targets in DNA-based diagnostics, which in turn can expedite disease diagnosis, assist farm management, and lead to better animal health and food security. The marker discovery strategy outlined herein requires less time, effort, and cost, and results in more markers compared with conventional methods. Identification of species-specific markers of other pathogens and corresponding infectious disease diagnostics are possible, conceivably improving health care and the economy.
Topics: Actinobacillus pleuropneumoniae; Animals; Bacterial Proteins; Genetic Markers; Genome, Bacterial; Pathology, Molecular; Pleuropneumonia; Polymerase Chain Reaction; Swine; Swine Diseases
PubMed: 34985298
DOI: 10.1128/spectrum.01311-21 -
Veterinary Research Jun 2015Gallibacterium anatis, a member of the Pasteurellaceae family, constitute a part of the normal micro-flora of the upper respiratory tract and the lower genital tract in... (Review)
Review
Gallibacterium anatis, a member of the Pasteurellaceae family, constitute a part of the normal micro-flora of the upper respiratory tract and the lower genital tract in chickens. However, increasing evidence indicate that G. anatis is also associated with a wide range of pathological changes, particularly in the reproductive organs, which leads to decreased egg production, lowered animal welfare and increased mortality. As a recently defined opportunistic pathogen limited focus has been placed on the pathogenesis and putative virulence factors permitting G. anatis to cause disease. One of the most studied virulence determinants is a large RTX-like toxin (GtxA), which has been demonstrated to induce a strong leukotoxic effect on avian macrophages. A number of fimbria of different sizes and shapes has been described. Particularly fimbriae belonging to the F17-like family appears to be common in a diverse selection of G. anatis strains. Mutants lacking the FlfA fimbria were severely attenuated in experimentally infected chickens. Additional characteristics including the ability to express capsular material possibly involved in serum resistance; secretion of metalloproteases capable of degrading immunoglobulins, and hemagglutinins, which may promote biofilm formation are all factors likely linked to the virulence of G. anatis. A major advantage for the study of how G. anatis interact with its host is the ability to perform biologically relevant experimental infections where natural routes of exposure allows reproduction of lesions observed during spontaneous infections. This review summarizes the current understanding of the G. anatis pathogenesis and discusses the contribution of the established and putative virulence factors described for this bacterium to date.
Topics: Animals; Chickens; Pasteurellaceae; Pasteurellaceae Infections; Poultry Diseases; Virulence; Virulence Factors
PubMed: 26063044
DOI: 10.1186/s13567-015-0206-z -
Critical Reviews in Microbiology Mar 2021is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and contributes to episodes of acute exacerbation... (Review)
Review
is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and contributes to episodes of acute exacerbation which are associated with increased hospitalization and mortality. Due to the ability of to adhere to host epithelial cells, initial colonization of the lower airways can progress to a persistent infection and biofilm formation. This is characterized by changes in bacterial behaviour such as reduced cellular metabolism and the production of an obstructive extracellular matrix (ECM). Herein we discuss the multiple mechanisms by which contributes to the pathogenesis of COPD. In particular, mechanisms that facilitate bacterial adherence to host airway epithelial cells, biofilm formation, and microbial persistence through immune system evasion and antibiotic tolerance will be discussed.
Topics: Animals; Bacterial Adhesion; Haemophilus Infections; Haemophilus influenzae; Humans; Lung; Pulmonary Disease, Chronic Obstructive
PubMed: 33455514
DOI: 10.1080/1040841X.2020.1863330 -
Microbial Genomics Sep 2018Haemophilus influenzae, originally named Pfeiffer's bacillus after its discoverer Richard Pfeiffer in 1892, was a major risk for global health at the beginning of the... (Review)
Review
Haemophilus influenzae, originally named Pfeiffer's bacillus after its discoverer Richard Pfeiffer in 1892, was a major risk for global health at the beginning of the 20th century, causing childhood pneumonia and invasive disease as well as otitis media and other upper respiratory tract infections. The implementation of the Hib vaccine, targeting the major capsule type of H. influenzae, almost eradicated the disease in countries that adapted the vaccination scheme. However, a rising number of infections are caused by non-typeable H. influenzae (NTHi), which has no capsule and against which the vaccine therefore provides no protection, as well as other serotypes equally not recognised by the vaccine. The first line of treatment is ampicillin, but there is a steady rise in ampicillin resistance. This is both through acquired as well as intrinsic mechanisms, and is cause for serious concern and the need for more surveillance. There are also increasing reports of new modifications of the intrinsic ampicillin-resistance mechanism leading to resistance against cephalosporins and carbapenems, the last line of well-tolerated drugs, and ampicillin-resistant H. influenzae was included in the recently released priority list of antibiotic-resistant bacteria by the WHO. This review provides an overview of ampicillin resistance prevalence and mechanisms in the context of our current knowledge about population dynamics of H. influenzae.
Topics: Ampicillin; Anti-Bacterial Agents; Drug Resistance, Bacterial; Haemophilus influenzae; Microbial Interactions; Plasmids; beta-Lactams
PubMed: 30207515
DOI: 10.1099/mgen.0.000214 -
Scientific Reports Jun 2023Respiratory diseases caused by Mannheimia haemolytica (M. haemolytica) and Pasteurella multocida (P. multocida) have been known to result in a considerable loss due to...
Identification of serotypes of Mannheimia haemolytica and Pasteurella multocida from pneumonic cases of sheep and goats and their antimicrobial sensitivity profiles in Borana and Arsi zones, Ethiopia.
Respiratory diseases caused by Mannheimia haemolytica (M. haemolytica) and Pasteurella multocida (P. multocida) have been known to result in a considerable loss due to mortality and reduced production. This study aimed at isolation and identification of M. haemolytica and P. multocida associated with pneumonic pasteurellosis in sheep and goats using bacteriological and molecular techniques. Identification of serotypes of M. haemolytica and P. multocida was done using indirect haemagglutination test. The in vitro antimicrobial sensitivity profiles of the M. haemolytica were tested using standard disk diffusion method. A total of 52 and 78 nasal swabs were collected from pneumonic cases for bacterial isolation and identification in Borana and Arsi zone, respectively. Four hundred sera samples were collected for identification of serotypes. The results showed that 17 of 52 (32.69%; 95% CI 20.33, 47.11) nasal swabs collected from pneumonic animals in Borana yielded positive results for Pasteurella/Mannheimia species, 13 (25.00%; 95% CI 14.03, 38.95) of which were M. haemolytica. None of the samples yielded P. multocida. Twenty-three of 78 (29.49%; 95% CI 19.69, 40.89) nasal swabs collected at Arsi from pneumonic animals yielded positive results for M. haemolytica (17) and P. multocida (6). Secondary biochemical characterization revealed that 14 of the 17 isolates conform to M. haemolytica whereas none of the 6 isolates suspected to be P. mutocida were confirmed. Eleven (84.62%) isolates from Borana and 4 (28.57%) from Arsi were confirmed to be M. haemolytica using PCR targeting the Rpt2 genes. Assay for M. haemolytica serotype A1 revealed all belong to A1. None of the isolates with cultural and morphological features of P. multocida gave positive results by molecular assay. Serological assay identified three serotypes of M. haemolytica namely A1, A2 and A7 almost in all of the samples whereas P. multocida serotype A was detected in 78.75% of the samples. The M. haemolytica isolates tested for susceptibility to antibiotics showed resistance against Bacitracin (83.33%) and Penicillin (50.00%) while they were found susceptible to Gentamycin (100%), Chloramphenicol (100%) and Sulfamethoxazole (100%) and Tetracycline (83.33%). In conclusion, the results of the present study revealed the association of M. haemolytica with pneumonic pasteurellosis in sheep and goats and can be of use in vaccine development in Ethiopia. Nevertheless, further investigations and continuous monitoring of antimicrobial resistance and appropriate selection and prudent use of antimicrobials in livestock sector are required.
Topics: Cattle; Animals; Sheep; Mannheimia haemolytica; Pasteurella multocida; Pasteurellosis, Pneumonic; Serogroup; Ethiopia; Goats; Pasteurella; Anti-Bacterial Agents; Sheep Diseases
PubMed: 37268660
DOI: 10.1038/s41598-023-36026-2 -
Veterinary Microbiology Jun 2022Animal husbandry requires practical measures to limit antimicrobial resistance (AMR). Therefore, a novel management and housing concept for veal calf fattening was...
Antimicrobial susceptibility in E. coli and Pasteurellaceae at the beginning and at the end of the fattening process in veal calves: Comparing 'outdoor veal calf' and conventional operations.
Animal husbandry requires practical measures to limit antimicrobial resistance (AMR). Therefore, a novel management and housing concept for veal calf fattening was implemented on 19 intervention farms (IF) and evaluated regarding its effects on AMR in Escherichia (E.) coli, Pasteurella (P.) multocida and Mannheimia (M.) haemolytica in comparison with 19 conventional control farms (CF). Treatment intensity (-80%) and mortality (-50%) were significantly lower in IF than in CF, however, production parameters did not differ significantly between groups. Rectal and nasopharyngeal swabs were taken at the beginning and the end of the fattening period. Susceptibility testing by determination of the minimum inhibitory concentration was performed on 5420 isolates. The presence of AMR was described as prevalence of resistant isolates (%), by calculating the Antimicrobial Resistance Index (ARI: number of resistance of one isolate to single drugs/total number of drugs tested), by the occurrence of pansusceptible isolates (susceptible to all tested drugs, ARI=0), and by calculating the prevalence of multidrug (≥3) resistant isolates (MDR). Before slaughter, odds for carrying pansusceptible E. coli were higher in IF than in CF (+65%, p=0.022), whereas ARI was lower (-16%, p=0.003), and MDR isolates were less prevalent (-65%, p=0.001). For P. multocida, odds for carrying pansusceptible isolates were higher in IF before slaughter compared to CF (+990%, p=0.009). No differences between IF and CF were seen regarding the prevalence of pansuceptible M. haemolytica. These findings indicate that easy-to-implement measures to improve calf management can lead to a limitation of AMR in Swiss veal fattening farms.
Topics: Animal Husbandry; Animals; Anti-Bacterial Agents; Anti-Infective Agents; Cattle; Drug Resistance, Bacterial; Escherichia coli; Microbial Sensitivity Tests; Pasteurellaceae; Red Meat
PubMed: 35576692
DOI: 10.1016/j.vetmic.2022.109419 -
Pharmaceutical Medicine Jan 2021The high incidence of error reports received by the US Food and Drug Administration (FDA) involving 2-component vaccines led to collaboration between the United States...
The high incidence of error reports received by the US Food and Drug Administration (FDA) involving 2-component vaccines led to collaboration between the United States Pharmacopeia (USP) and the Institute for Safe Medication Practices (ISMP). This collaborating group sought to further understand errors associated with all 2-component vaccines (i.e. vaccine components provided by the manufacturer in physically separate containers) and to provide safe practice strategies for storing, preparing, dispensing, and administering these vaccines as intended. Fourteen available 2-component vaccines were identified. The ISMP National Vaccine Errors Reporting Program (VERP) and the FDA Vaccine Adverse Event Reporting System (VAERS) were searched from the initiation of each respective reporting system through December 31, 2019. The three vaccines with the most reported reconstitution errors in the VERP and VAERS are Menveo (meningococcal), Pentacel (DTaP, Polio, Haemophilus influenzae type b), and ActHIB [H. influenzae type b (Hib)]. Manufacturers should design labeling and packaging of vaccines to provide ease of storage and fail-safe preparation to prevent 2-component vaccine errors. Implementing risk reduction strategies, such as training healthcare professionals and affixing storage bin labels, remind healthcare professionals to mix the 2-components and facilitate appropriate administration.
Topics: Adverse Drug Reaction Reporting Systems; Bacterial Vaccines; Haemophilus influenzae type b; Meningococcal Vaccines; United States; United States Food and Drug Administration
PubMed: 33151497
DOI: 10.1007/s40290-020-00362-9 -
Microbial Genomics Feb 2022is a Gram-negative, rod-shaped bacterium of the family causing pig pleuropneumonia associated with great economic losses worldwide. Nineteen serotypes with distinctive...
is a Gram-negative, rod-shaped bacterium of the family causing pig pleuropneumonia associated with great economic losses worldwide. Nineteen serotypes with distinctive lipopolysaccharide (LPS) and capsular (CPS) compositions have been described so far, yet complete circular genomes are publicly available only for the reference strains of serotypes 1, 4 and 5b, and for field strains of serotypes 1, 3, 7 and 8. We aimed to complete this picture by sequencing the reference strains of 17 different serotypes with the MinION sequencer (Oxford Nanopore Technologies, ONT) and on an Illumina HiSeq (Illumina) platform. We also included two field isolates of serotypes 2 and 3 that were PacBio- and MinION-sequenced, respectively. Genome assemblies were performed following two different strategies, i.e. PacBio- or ONT-only assemblies polished with Illumina reads or a hybrid assembly by directly combining ONT and Illumina reads. Both methods proved successful in obtaining accurate circular genomes with comparable qualities. blast-based genome comparisons and core-genome phylogeny based on core genes, SNP typing and multi-locus sequence typing (cgMLST) of the 26 circular genomes indicated well-conserved genomes across the 18 different serotypes, differing mainly in phage insertions, and CPS, LPS and RTX-toxin clusters, which, consistently, encode serotype-specific antigens. We also identified small antibiotic resistance plasmids, and complete subtype I-F and subtype II-C CRISPR-Cas systems. Of note, highly similar clusters encoding all those serotype-specific traits were also found in other pathogenic and commensal species. Taken together with the presence of transposable elements surrounding these loci, we speculate a dynamic intra- and interspecies exchange of such virulence-related factors by horizontal gene transfer. In conclusion, our comprehensive genomics analysis provides useful information for diagnostic test and vaccine development, but also for whole-genome-based epidemiological studies, as well as for the surveillance of the evolution of antibiotic resistance and virulence genes in .
Topics: Actinobacillus pleuropneumoniae; Animals; Genomics; Lipopolysaccharides; Multilocus Sequence Typing; Serogroup; Swine
PubMed: 35196217
DOI: 10.1099/mgen.0.000776 -
Veterinary Medicine and Science Jul 2023Small ruminants are the most numerous of man's domestic livestock. Although sheep represent a great resource for Ethiopia, the net rate of productivity per animal is...
Isolation and identification of Mannheimia haemolytica and Pasteurella multocida from symptomatic and asymptomatic sheep and their antibiotic susceptibility patterns in three selected districts of north Gondar zone, Gondar Ethiopia.
BACKGROUND
Small ruminants are the most numerous of man's domestic livestock. Although sheep represent a great resource for Ethiopia, the net rate of productivity per animal is very low due to many factors including respiratory disorders.
OBJECTIVES
The objectives of this work were to isolate and identify M. haemolytica and P. multocida as well as to assess the antibiotic susceptibility patterns of these isolates. Nasal swab samples were collected aseptically by using 70% alcohol as a disinfectant.
METHODS
A cross-sectional study was conducted in three selected districts of the north Gondar zone, Ethiopia.
RESULTS
From 148 samples collected in 94 (63.5%) asymptomatic and 54 (35.5%) symptomatic sheep, a total of 23 were isolated successfully based on cultural, staining, and biochemical characteristics. Of these isolates, 18 (78.3%) and 5 (21.7%) were M. haeimolytica and P. multocida, respectively. Compared with the total animals examined, the proportion of M. haeimolytica and P. multocida were 12.16 % (n = 18) and 3.38% (n = 5), respectively. All of the isolates were subjected to a panel of 8 antibiotic discs for sensitivity testing. Of the tested antibiotics, chloramphenicol (100%), gentamicin, and tetracycline (82.6%) each and co-trimoxazole (60.8%) were found to be the most effective drugs whereas, both species were completely resistant to vancomycin and showed a very low degree of susceptibility for the rest drugs.
CONCLUSIONS
In conclusion, M. haemolytica was found to be the predominant isolate in all host-related factors and most of the antibiotics were not fully effective against the isolates. Hence, treatment and/or vaccination of ovine pneumonic pasteurellosis should be emphasised to M. haeimolytica using the most effective drugs along with appropriate herd management practices.
Topics: Sheep; Animals; Mannheimia haemolytica; Pasteurella multocida; Ethiopia; Cross-Sectional Studies; Anti-Bacterial Agents
PubMed: 37197762
DOI: 10.1002/vms3.1166 -
FEBS Open Bio Dec 2022Nontypeable Haemophilus influenzae (NTHi) has emerged as a dominant mucosal pathogen causing acute otitis media (AOM) in children, acute sinusitis in children and...
Nontypeable Haemophilus influenzae (NTHi) has emerged as a dominant mucosal pathogen causing acute otitis media (AOM) in children, acute sinusitis in children and adults, and acute exacerbations of chronic bronchitis in adults. Consequently, there is an urgent need to develop a vaccine to protect against NTHi infection. A multi-component vaccine will be desirable to avoid emergence of strains expressing modified proteins allowing vaccine escape. Protein D (PD), outer membrane protein (OMP) 26, and Protein 6 (P6) are leading protein vaccine candidates against NTHi. In pre-clinical research using mouse models, we found that recombinantly expressed PD, OMP26, and P6 induce robust antibody responses after vaccination as individual vaccines, but when PD and OMP26 were combined into a single vaccine formulation, PD antibody levels were significantly lower. We postulated that PD and OMP26 physiochemically interacted to mask PD antigenic epitopes resulting in the observed effect on antibody response. However, column chromatography and mass spectrometry analysis did not support our hypothesis. We postulated that the effect might be in vivo through the mechanism of protein vaccine immunologic antigenic competition. We found when PD and OMP26 were injected into the same leg or separate legs of mice, so that antigens were immunologically processed at the same or different regional lymph nodes, respectively, antibody levels to PD were significantly lower with same leg vaccination. Different leg vaccination produced PD antibody levels quantitatively similar to vaccination with PD alone. We conclude that mixing PD and OMP26 into a single vaccine formulation requires further formulation studies.
Topics: Mice; Animals; Haemophilus Vaccines; Bacterial Outer Membrane Proteins; Antibodies, Bacterial; Immunoglobulin G; Haemophilus influenzae
PubMed: 36263849
DOI: 10.1002/2211-5463.13498