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Polish Journal of Microbiology Jun 2018Brucellae are Gram-negative, small rods infecting mammals and capable of causing disease called brucellosis. The infection results in abortion and sterility in domestic... (Review)
Review
Brucellae are Gram-negative, small rods infecting mammals and capable of causing disease called brucellosis. The infection results in abortion and sterility in domestic animals (sheeps, pigs, rams etc). Especially dangerous for humans are: Brucella melitensis, Brucella suis, Brucella abortus, and Brucella canis that trigger unspecific symptoms (flu-like manifestation). Brucella rods are introduced via host cells, by inhalation, skin abrasions, ingestion or mucosal membranes. The most important feature of Brucella is the ability to survive and multiply within both phagocytic and non-phagocytic cells. Brucella does not produce classical virulence factors: exotoxin, cytolisins, exoenzymes, plasmids, fimbria, and drug resistant forms. Major virulence factors are: lipopolysaccharide (LPS), T4SS secretion system and BvrR/BvrS system, which allow interaction with host cell surface, formation of an early, late BCV (Brucella Containing Vacuole) and interaction with endoplasmic reticulum (ER) when the bacteria multiply. The treatment of brucellosis is based on two-drug therapy, the most common combinations of antibiotics are: doxycycline with rifampicin or fluoroquinolones with rifampicin. Currently, also other methods are used to disrupt Brucella intracellular replication (tauroursodeoxycholic acid or ginseng saponin fraction A).
Topics: Animals; Anti-Bacterial Agents; Brucella; Brucellosis; Endoplasmic Reticulum; Host-Pathogen Interactions; Humans; Lipopolysaccharides; Macrophages; Sheep; Swine; Type IV Secretion Systems; Virulence Factors
PubMed: 30015453
DOI: 10.21307/pjm-2018-029 -
Frontiers in Veterinary Science 2021Canine brucellosis is an infectious and zoonotic disease caused by , which has been reported worldwide, and is a major public health concern due to close contact between... (Review)
Review
Canine brucellosis is an infectious and zoonotic disease caused by , which has been reported worldwide, and is a major public health concern due to close contact between dogs and humans. In dogs, canine brucellosis manifests with abortion outbreaks, reproductive failure, enlargement of lymph nodes, and occasionally affects the osteoarticular system, although the occurrence of asymptomatic infections in dogs are not uncommon. In humans, the disease is associated with a febrile syndrome, commonly with non-specific symptoms including splenomegaly, fatigue, and weakness. Infection of dogs occurs mostly by the oronasal route when in contact with contaminated tissues such as aborted fetuses, semen, urine, and vaginal secretions. In humans, contact with contaminated fluids from infected dogs is an important source of infection, and it is an occupational risk for veterinarians, breeders, laboratory workers, among other professionals who deal with infected animals or biological samples. The diagnosis in dogs is largely based on serologic methods. However, serologic diagnosis of canine brucellosis remains very challenging due to the low accuracy of available tests. Molecular diagnostic methods have been increasingly used in the past few years. Treatment of infected dogs is associated with a high frequency of relapse, and should be employed only in selected cases. Currently there are no commercially available vaccines for prevention of canine brucellosis. Therefore, development of novel and improved diagnostic methods as well as the development of efficacious and safe vaccination protocols are needed for an effective control of canine brucellosis and its associated zoonotic risk.
PubMed: 33738302
DOI: 10.3389/fvets.2021.594291 -
Pathogens (Basel, Switzerland) Dec 2021spp. are Gram-negative, non-motile, non-spore-forming, slow-growing, facultative intracellular bacteria causing brucellosis. Brucellosis is an endemic of specific... (Review)
Review
spp. are Gram-negative, non-motile, non-spore-forming, slow-growing, facultative intracellular bacteria causing brucellosis. Brucellosis is an endemic of specific geographic areas and, although underreported, represents the most common zoonotic infection, with an annual global incidence of 500,000 cases among humans. Humans represent an occasional host where the infection is mainly caused by , which is the most virulent; ; ; and . A microbiological analysis is crucial to identifying human cases because clinical symptoms of human brucellosis are variable and aspecific. The laboratory diagnosis is based on three different microbiological approaches: (i) direct diagnosis by culture, (ii) indirect diagnosis by serological tests, and (iii) direct rapid diagnosis by molecular PCR-based methods. Despite the established experience with serological tests and highly sensitive nucleic acid amplification tests (NAATs), a culture is still considered the "gold standard" in the laboratory diagnosis of brucellosis due to its clinical and epidemiological relevance. Moreover, the automated BC systems now available have increased the sensitivity of BCs and shortened the time to detection of species. The main limitations of serological tests are the lack of common interpretative criteria, the suboptimal specificity due to interspecies cross-reactivity, and the low sensitivity during the early stage of disease. Despite that, serological tests remain the main diagnostic tool, especially in endemic areas because they are inexpensive, user friendly, and have high negative predictive value. Promising serological tests based on new synthetic antigens have been recently developed together with novel point-of-care tests without the need for dedicated equipment and expertise. NAATs are rapid tests that can help diagnose brucellosis in a few hours with high sensitivity and specificity. Nevertheless, the interpretation of NAAT-positive results requires attention because it may not necessarily indicate an active infection but rather a low bacterial inoculum, DNA from dead bacteria, or a patient that has recovered. Refined NAATs should be developed, and their performances should be compared with those of commercial and home-made molecular tests before being commercialized for the diagnosis of brucellosis. Here, we review and report the most common and updated microbiological diagnostic methods currently available for the laboratory diagnosis of brucellosis.
PubMed: 34959578
DOI: 10.3390/pathogens10121623 -
Emerging Microbes & Infections Dec 2023The zoonotic bacteria, , is becoming the leading cause of canine brucellosis in Europe. In dogs, it causes reproductive problems as well as non-specific lameness or... (Review)
Review
The zoonotic bacteria, , is becoming the leading cause of canine brucellosis in Europe. In dogs, it causes reproductive problems as well as non-specific lameness or discospondilitis. In humans, can be origin of chronic debilitating conditions characteristic to its genus such as undulant fever, splenomegaly, and lymphadenopathy. Although shows some pathogenic characteristics similar to and , it lacks surface O-polysaccharide, like nonzoonotic . This review shows that host- interactions are still poorly understood, with many knowledge and capability gaps, causing relatively poor sensitivity and specificity of existing diagnostic tools. Currently, there is no vaccine for this rough species. Besides, antimicrobial therapy does not guarantee bacterial elimination, and infection relapses are frequently reported, increasing the risks of antibiotic resistance development. has been detected in dogs in almost all European countries which increased human exposure, but currently there is no systematic surveillance. Moreover, caused brucellosis is not included in Animal Health Law, and therefore there is no legal framework to tackle this emerging infectious disease. To map out the diagnostic strategies, identify risks for human infections and propose management scheme for infected pet and kennel dogs, we present current understanding of canine caused brucellosis, outline major knowledge gaps and propose future steps. To address and highlight challenges veterinary and public health services encounter in Europe, we developed two infection scenarios: of a single household pet and of a kennel dog in larger group.
Topics: Animals; Dogs; Humans; Sheep; Brucella canis; Public Health; Dog Diseases; Brucellosis; Europe
PubMed: 37649455
DOI: 10.1080/22221751.2023.2249126 -
The Canadian Veterinary Journal = La... Jan 2018In Canada, remains a potentially devastating infectious agent that is still considered uncommon, despite the increasing international movement of dogs. There may be a... (Review)
Review
In Canada, remains a potentially devastating infectious agent that is still considered uncommon, despite the increasing international movement of dogs. There may be a growing risk to the Canadian canine population due to a reliance on outdated seroprevalence studies and the lack of federal regulation. With the complex diagnostic and management challenges associated with a One Health approach is necessary to address the need for ongoing research, including updating canine and human seroprevalence rates in Canada, elucidating the pathogenesis, and determining the most appropriate treatment and prevention strategies. Clinical management decisions are often complicated by currently available treatment protocols, and health risks to both canine and human populations. This article integrates recent research focusing on the pathogenesis, diagnosis, and treatment of and outlines current clinical management approaches.
Topics: Animals; Brucella canis; Brucellosis; Canada; Dog Diseases; Dogs
PubMed: 29302106
DOI: No ID Found -
Frontiers in Veterinary Science 2022To describe the clinical and imaging findings of 33 dogs with discospondylitis (BDS).
OBJECTIVE
To describe the clinical and imaging findings of 33 dogs with discospondylitis (BDS).
ANIMALS
33 client owned dogs from four veterinary specialty hospitals within Colorado and Arizona with at least one positive test and spinal diagnostic imaging.
PROCEDURES
Retrospective review of signalment, physical and neurological examination findings, laboratory results, serology, and diagnostic imaging of 33 dogs with BDS. All imaging was reviewed by a board-certified veterinary neurologist. Radiographs were reviewed by a board-certified veterinary radiologist blinded to MRI and CT findings.
RESULTS
31/33 (94%) dogs were <5 years old (median = 2.5 years, mean = 2.9 years, range 0.5-10 years). 21/29 (72%) dogs had signs of nonspecific pain, spinal pain, or lameness for >3 months (median = 6 months, mean = 8.2 months, range 5 days-4 years). Fever was seen in only 4/28 (14%) dogs. Multifocal lesions were evident on radiographs in 21/29 (72%) dogs and MRI in 12/18 (67%) dogs. Smooth, round, central end-plate lysis, defined as "hole punch" lesions, were identified radiographically in 25/29 (86%) dogs. Vertebral physitis or spondylitis without discitis was evident on MRI in 7/18 (39%) dogs.
CLINICAL RELEVANCE
Dogs with BDS typically present at a young age with a long duration of clinical signs. Identification of radiographic "hole punch" lesions and MRI evidence of vertebral physitis, spondylitis, and paravertebral inflammation without discitis should increase suspicion for BDS. BDS may be increasing in frequency in the southwestern United States, and dogs with signs of chronic spinal pain and/or lameness should be screened for .
PubMed: 36406064
DOI: 10.3389/fvets.2022.1043610 -
Microorganisms Aug 2022Brucellosis is one of the most important and widespread bacterial zoonoses worldwide. Cases are reported annually across the range of known infectious species of the... (Review)
Review
Brucellosis is one of the most important and widespread bacterial zoonoses worldwide. Cases are reported annually across the range of known infectious species of the genus Globally, , primarily hosted by domestic sheep and goats, affects large proportions of livestock herds, and frequently spills over into humans. While some species, such as , are well controlled in livestock in areas of North America, the Greater Yellowstone Ecosystem supports the species in native wild ungulates with occasional spillover to livestock. Elsewhere in North America, other species still infect domestic dogs and feral swine, with some associated human cases. spp. patterns vary across space globally with and the most important for livestock control. A myriad of other species within the genus infect a wide range of marine mammals, wildlife, rodents, and even frogs. Infection in humans from these others varies with geography and bacterial species. Control in humans is primarily achieved through livestock vaccination and culling and requires accurate and rapid species confirmation; vaccination is spp.-specific and typically targets single livestock species for distribution. Traditional bacteriology methods are slow (some media can take up to 21 days for bacterial growth) and often lack the specificity of molecular techniques. Here, we summarize the molecular techniques for confirming and identifying specific species and provide recommendations for selecting the appropriate methods based on need, sensitivity, and laboratory capabilities/technology. As vaccination/culling approaches are costly and logistically challenging, proper diagnostics and species identification are critical tools for targeting surveillance and control.
PubMed: 36014002
DOI: 10.3390/microorganisms10081584 -
Revista Argentina de Microbiologia 2021The aim of this study was to estimate the diversity and prevalence of both groups of Brucella canis 1 and 2 with and without deletion respectively in different areas of...
The aim of this study was to estimate the diversity and prevalence of both groups of Brucella canis 1 and 2 with and without deletion respectively in different areas of Argentina. A total of 104 bacterial cultures were typed as B. canis strains using the classical biotyping method. Two PCR assays were performed to confirm that all isolates were B. canis and not Brucella suis. The differentiation between groups 1 and 2 was achieved using another PCR assay and the diversity of B. canis isolates was assessed with four MLVA_16 markers. All strains belonged to Group 2. Bruce 09 marker (MLVA_16 assay) showed the greatest diversity. Only Group 2 of B. canis was identified among the strains evaluated. The markers chosen from the MLVA_16 allowed us to detect genetic diversity among the strains of B. canis studied.
Topics: Argentina; Brucella canis; Brucella suis; Brucellosis; Humans; Polymerase Chain Reaction
PubMed: 33176954
DOI: 10.1016/j.ram.2020.06.012 -
Frontiers in Immunology 2022is the cause of canine brucellosis, a globally distributed, zoonotic pathogen which primarily causes disease in dogs. is unique amongst the zoonotic spp. with its...
is the cause of canine brucellosis, a globally distributed, zoonotic pathogen which primarily causes disease in dogs. is unique amongst the zoonotic spp. with its rough lipopolysaccharide, a trait typically associated with attenuation in gram-negative bacteria. Unfortunately, no vaccine is available against , and vaccine development is hampered by a limited understanding of the immune response required to combat it and the course of infection following a physiologically relevant, mucosal route of inoculation. To address these concerns and analyze the impact of the rough phenotype on the immune response, we infected mice intratracheally with rough or smooth or . Bacterial colonization and histologic lesions were assessed in systemic target organs as well as locally in the lungs and draining mediastinal lymph node. Mice were also reinfected with following antibiotic treatment and cytokine production by T lymphocytes in the lung and spleen was assessed by flow cytometry to investigate the memory immune response. Despite its rough phenotype, established a persistent infection at the same level of colonization as the smooth strains. However, induced significantly less granulomatous inflammation in the spleen as well as a lack of bronchial-associated lymphoid tissue (BALT) hyperplasia in the lungs. These differences coincided with increased IL-10 and decreased IFN-γ in the spleen of -infected mice. Previous exposure to all strains provided protection against colonization following secondary challenge, although induction of IFN-γ by T lymphocytes was seen only in the lungs during infection while the smooth strains induced this cytokine in the spleen as well. Neither strain induced significant polyfunctional T lymphocytes, a potential immunomodulatory mechanism that appears to be independent of lipopolysaccharide phenotype.
Topics: Animals; Brucella abortus; Brucella canis; Brucella melitensis; Brucellosis; Cytokines; Immunity; Immunologic Memory; Lipopolysaccharides; Mice
PubMed: 36032120
DOI: 10.3389/fimmu.2022.959328