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|pagetitle =Bordetella species
 
|pagetitle =Bordetella species
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|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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===Overview===
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*[[Bordetella bronchiseptica|''B. bronchiseptica'']] infects a wide range of animal species worldwide
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*[[Bordetella avium|''B. avium'']] resticted to birds
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*Normal inhabitants of upper respiratory tract
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*Cause repsiratory diseases including rhinitis, tracheitis, bronchitis and bronchiolitis
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*Exogenous or endogenous infection
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*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 [[Bordetella bronchiseptica|''B. bronchiseptica'']] - 1 diagnostic antigen
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*[[Bordetella bronchiseptica|''B. bronchiseptica'']] haemolytic, whereas [[Bordetella avium|''B. avium'']] not
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*Affinity for ciliated respiratory epithelium
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===Pathogenesis and pathogenicity===
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*Use pathogenicity factors such as filamentous haemagglutanin (only [[Bordetella bronchiseptica|''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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