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Species/Subspecies: Chlamydophila psittaci
Etymology: Genus name: cloac loving.
Species epithet: of a parrot.
Significance:  [Very important]   
Old 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.
Hosts: Birds and humans, but other animal species can also suffer from the disease.
Reservoir: Birds. C. psittaci is common i wild birds and more than 100 different species have been reported to transmit the disease.
Disease:Psittacosis (parrot fever) in humans and ornithosis in birds. The disease is zoonotic. The disease can be transmitted between humans although it is uncommon.
Clinical Picture: Infected birds may be asymptomatic, but can also exhibit symptoms such as trouble in breathing, diarrhea, refusal to eat or runny nose. C. psittaci causes atypical and severe pneumonia in humans with early 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 

Chlamydophila psittaci  
Five species have been described within genus Chlamydia and six species have been described within genus Chlamydophila. Species within the family Chlamydiaceae form two relatively distinct clusters and have, therefore, been divided into two genera Chlamydia and Chlamydophila. However, some research groups have not accepted this, but include all species within genus Chlamydia.
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
Links: The comprehensive reference and education wiki on Chlamydia and the Chlamydiales, Klamydia-föreläsning

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