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| − | ===Overview=== | + | {{frontpage |
| | + | |pagetitle =Bordetella species |
| | + | |pagebody =The ''Bordetella'' species are Gram negative rods. They are normal inhabitants of the upper respiratory tract, although can cause repsiratory diseases including rhinitis, tracheitis, bronchitis and bronchiolitis. |
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| − | *''B. bronchiseptica'' infects a wide range of animal species worldwide
| + | |contenttitle =Content |
| − | *''B. avium'' resticted to birds
| + | |contentbody =<big><b> |
| − | *Normal inhabitants of upper respiratory tract
| + | <categorytree mode=pages>Bordetella species</categorytree> |
| − | *Cause repsiratory diseases including rhinitis, tracheitis, bronchitis and bronchiolitis
| + | </b></big> |
| − | *Exogenous or endogenous infection
| + | |logo =bugs-logo copy.png |
| − | *Poor survival in the environment
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| − | *Transmission between animals
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| − | *Young animals particularly susceptible
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| − | *Predisposing factors include stress and concurrent infections
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| − | *High morbidity; low mortality
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| − | ===Characteristics===
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| − | *Gram negative rods
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| − | *Strict aerobes
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| − | *Grow slowly
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| − | *Catalase and oxidase positive
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| − | *Non-lactose fermentors
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| − | *Grow on MacConkey agar
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| − | *Toxigenic strains agglutinate mammalian red blood cells
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| − | *Identical S form LPS in all strains of ''B. bronchiseptica'' - 1 diagnostic antigen
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| − | *''B. bronchiseptica'' haemolytic, whereas ''B. avium'' not
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| − | *Affinity for ciliated respiratory epithelium
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| − | | + | [[Category:Bacterial Organisms]] |
| − | ===Pathogenesis and pathogenicity===
| + | [[Category:Gram_negative_bacteria]] |
| − | | + | [[Category:Rods]] |
| − | *Use pathogenicity factors such as filamentous haemagglutanin (only ''B. bronchiseptica''), fimbriae and pertactin to adhere to ciliated respiratory epithelium
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| − | *Produce toxins:
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| − | **Adenylate cyclase (leucocyte toxin - kills phagocytes) (only ''B. bronchiseptica'')
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| − | **Tracheal cytotoxin (inhibits DNA synthesis in ciliated cells)
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| − | **Dermonecrotic toxin
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| − | *Pathogenicity factors activated by environment and genetic changes
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| − | *Regulatory locus, BvgAS, mediates the activation
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| − | *Phase variation: genetic switch of Bvg locus allows transciption of pathogenicity factors
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| − | *Phenotypic modulation: temperature, magnesium ions and nicotinic acid affect expression of pathogenicity factors
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| − | *Bvg positive allows expression of pathogenicity factors and toxins and colonisation
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| − | *Bvg negative may allow survival in the environment with production of flagellae
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| − | *Mucosal IgA prevent attachment of bacteria to cilia, but clearance from the respiratory tract may take weeks
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| − | *Carrier animals are a source of infection
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| − | ===Diagnosis===
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| − | *Samples include nasal swabs, tracheal aspirates and exudates
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| − | *Cultured on blood agar and MacConkey agar
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| − | *Biochemical profiles
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| − | *Slide agglutination tests for virulence of isolates
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| − | ===Infectious canine tracheitis/Kennel cough===
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| − | *''B. bronchiseptica'' acts as a primary pathogen in [[Respiratory Viral Infections - Pathology#Infectious canine tracheitis|Infectious canine tracheitis]]
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| − | *Frequently isolated from dogs with respiratory disease
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| − | *Often found with viruses or mycoplasma
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| − | *Adheres to ciliated epithelial cells in the trachea
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| − | *Colonisation and proliferation in trachea
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| − | *Releases toxins causing epithelial necrosis and prevents ciliary clearance
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| − | *Irritation to tract causes coughing
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| − | *Mortality rates low
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| − | *Peribronchial inflammation and [[Lungs Inflammatory - Pathology#Bronchopneumonia|bronchopneumonia]]
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| − | can result in unvaccinated puppies or immunosuppressed dogs
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| − | *Severe pneumonia following secondary infection e.g. with [[streptococci|Streptococci]]
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| − | *Fatal [[Lungs Inflammatory - Pathology#Bronchopneumonia|bronchopneumonia]] if occurs secondary to [[Paramyxoviridae#Canine distemper virus|canine distemper virus]]
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| − | *Transmission via respiratory secretions by direct contact or aerosol and on fomites
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| − | *Clinical signs:
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| − | **Develop within 3-4 days; persist for up to 2 weeks
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| − | **Coughing
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| − | **Gagging
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| − | **Mild serous oculonasal discharge
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| − | *Treatments includes antibiotics if coughing persists or bronchopneumonia develops
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| − | *Live intranasal vaccines
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| − | *Also found in respiratory tract of cats; can cause pneumonia in kittens; vaccine available
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| − | ===Atrophic Rhinitis===
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| − | *''B. bronchiseptica'' causes [[Nasal Cavity Inflammatory - Pathology#Bacterial rhinitis|Atrophic rhinitis of pigs]] in association with [[Pasteurella species and Mannheimia haemolytica|''Pasteurella multocida'']]
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| − | *Colonises nasopharynx
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| − | *Infection must occur during first few weeks of life
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| − | *Produces dermonecrotic toxin which damages osteoblasts, preventing bone formation
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| − | *Leads to turbinate atrophy without distortion of the snout in uncomplicated infections
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| − | *[[Nasal Cavity Inflammatory - Pathology#Bacterial rhinitis|Atrophic rhinitis]] results when [[Pasteurella species and Mannheimia haemolytica|''Pateurella multocida'']] colonises and produces osteolytic toxin, leading to bone resorption
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| − | *Malformation of snout in growing pigs as well as poor growth
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| − | *increases with high stocking density and poor ventilation
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| − | *Vaccine available
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| − | ===Turkey coryza===
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| − | *A highly infectious upper respiratory tract infection of poults caused by ''B. avium''
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| − | *High morbidity, low mortality
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| − | *Infection spread by direct contact, aerosol and from the environment
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| − | *Rhinotracheitis
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| − | *Mucus accumulation in the nares
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| − | *Swelling of maxillary sinuses
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| − | *Beak breathing, lacrimation, sneezing
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| − | *Predisposes to infection with [[Escherichia coli|''E. coli'']]
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| − | *Treatment with antibiotics
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| − | *Bacterin and modified live vaccines available[[Category:Bacteria]][[Category:Gram_negative_bacteria]]
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