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| − | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Chlamydophila species]] |
| − | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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| − | ''Chlamydophila psittaci'' involved in [[Nasal cavity - inflammatory#In Cats|feline rhinotracheitis]] together with [[Herpesviridae|herpes virus 1]] C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis, see [[Bacterial infections#Feline Chlamydiosis|feline chlamydiosis]]
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| − | *May cause [[Joints - inflammatory#In Sheep|arthritis in sheep]] and [[Joints - inflammatory#In Cattle|arthritis in cattle]]
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| − | ===Overview===
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| − | *Host adapted and non-host adapted species varying in virulence for different hosts
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| − | *Different species cause specific diseases in particular hosts
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| − | *Repsiratory, enteric, pleural and reproductive diseases in animals and humans
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| − | *Intestinal infections often subclinical and persistent
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| − | ===Characteristics===
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| − | *Obligate intracellular bacteria
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| − | *Gram negative bacteria with outer membrane, LPS, ribosomes, DNA and RNA
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| − | *Peptidoglycan cell wall resistant to lysozyme
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| − | *Only grow in presence of living eukaryotic cells
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| − | *Unable to synthesis ATP therefore require intermediates from host cells
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| − | *Grow in embyonated eggs and McCoy cells as well as animal tissues
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| − | *Not stained by Gram stain
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| − | *Kosters (modified Ziehl-Neelson, small red rods) or fluorescent antibody stain required for detection
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| − | *Blue inclusions in cytoplasm of Giemsa-stained cels
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| − | *Antigen detection kits for diagnosis from swabs
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| − | *Two morphological forms
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| − | **Elementary body, the infective extracellular form, which is small, metabolically inert and osmotically stable; surrounded by cytoplasmic membrane, outer membrane with LPS, but no peptidoglycan
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| − | **Retiuculate body: larger, metabolically active, osmotically fragile
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| − | *Elementary body survives in the environment for several days
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| − | ===Pathogenesis and pathogenicity===
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| − | *Elementary body enters host epithelial cells by receptor-mediated endocytosis
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| − | *Transformation into larger reticulate body within endosome; known as an inclusion
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| − | *Reticulate body divides by binary fission to form many new chlamydia cells
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| − | *Reticulate bodies mature and condense to form elementary bodies
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| − | *Elementary bodies released from dying host cells after about 72 hours to infect other cells
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| − | *Persistent infections can occur if replication delayed by environmental conditions
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| − | *Many infections subclinical due to intracellular existence of ''chlamydia'' preventing inflammatory reactions
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| − | *Chronic infections may fail to induce an immune response, or may repeatedly stimulate the immune system, causing a delayed hypersensitivity reaction and tissue damage
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| − | *Prolonged faecal shedding of organisms
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| − | *Clinical infections occur in non-natural host species
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| − | *CLinical signs depend on route of infection and degree of exposure
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| − | ===''Chlamydophila psittaci''===
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| − | *Causes notifiable psittacosis in birds
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| − | ===''Chlamydophila abortus''===
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| − | *Ovine enzootic abortion
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| − | *Contagious ovine abortion in late pregnancy
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| − | *Infection via ingestion or inhalation causes a bacteraemia
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| − | *Bacteria localise in placenta and cause placentitis, leading to abortion
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| − | *Abortion rates may reach 30%
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| − | *Fertility not impaired
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| − | *Survival of elementary bodies in faeces and wild birds are a source of infection from one lambing season to the next
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| − | *Ewes may be carriers for several years
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| − | *Venereal transmission from infected rams
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| − | *Some immunity develops after infection, protecting ewes from subsequent disease
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| − | *Vaccines prevent infection but will not clear infection from persistently-infected animals
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| − | *Vaccination of ewe lambs
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| − | ===''Chlamydophila felis''===
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| − | *Host adapted species in cats
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| − | *Feline interstitial pneumonia and conjunctivitis
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| − | *Diagnosis by antigen detection in ocular/nasal secretions - ELISA, PCR, Kosters, fluorescent antibody test
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| − | *Vaccine
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| − | ===Diagnosis===
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| − | ===Treatments===
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