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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Chlamydia psittaci
Categories: Zoonotic; notifiable diseases and bacteria
Etymology: Genus name: cloac loving.
Species epithet: of a parrot.
Significance:  [Very important]   
Alternative Species Name(s):Chlamydia psittaci
Type Strain: 6BC = ATCC VR-125.
Macromorphology (smell): Does only grow intracellularly and can, therfore, not be cultivated on artificial substrates.
Micromorphology: Outside the host cell: infectious elementary bodies (0.2-0.3 µm).
Within the host cell: non-infectious reticulate bodies (0.8-1.0 µm). C. psittaci is non-motile.
Gram +/Gram -:G-, difficult to gram stain.
Metabolism: Aerobic, but members of the family Chlamydiaceae have only limited resources to to synthesize their own ATP. Therefore, they can ingest ATP from the host cell.
Spec. Char.:
Special Media: Can be cultivated in cell cultures.
Reservoir: Birds. C. psittaci is common i wild birds and more than 100 different species have been reported to transmit the disease.
HostsDiseaseClinical picture
BirdsOrnithosisCould be asymptomatic, but also show symptoms such as difficulty breathing, diarrhea, inappetence and/or runny nose
HumansPsittacosis (parrot fever)Atypical and severe pneumonia with flu-like symptoms. Fatal cases have been reported.
Virulence Factors: The virulence factors of C. psittaci are unknown.
Genome Sequence:
Acc-noStrainSize (bp)Genome
CP002549 6BCT 1 171 660 1c + 1c 
At least 18 strains have been sequenced and 0-1 plasmid has been found.

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AB001778 6BCT 1 507 

Chlamydia psittaci  
Species within the family Chlamydiaceae were previously (1999) divided into two genera Chlamydia and Chlamydophila. However, the differences between these two genera were not that great and many research groups have not accepted this division. Therefore, the genus Chlamydophila has been returned (2015) to the genus Chlamydia. See the references below.
Legislation: In Sweden psittacosis is notifiable to the Swedish Board of Agriculture.
Comment:It is believed that several people have been infected with psittacosis in associated with cleaning of bird feeding tables. It is, therefore, very important to always clean bird tables outside and with extreme caution to avoid aerosol formation.

Elementary bodies from C. psittaci have been reported to survive in the environment outside the host for months.

Members of the family Chlamydiaceae are obligately intracellular. The cell envelope contains cystein rich proteins and only a small amount of peptidoglycans.

Reference(s): No. 68, 140, 177
Links: The comprehensive reference and education wiki on Chlamydia and the Chlamydiales, Klamydia-föreläsning

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