Chlamydophila psittaci

From Biology-Online Dictionary | Biology-Online Dictionary



An obligate gram-negative intracellular bacterium involved in avian chlamydiosis and respiratory psittacosis in humans.


Chlamydophila psittaci has a size of at least 0.5 micrometers which lacks peptidoglycan in the cell envelope but has an outer membrane with lipopolysaccharide and cytoplasmic bilayer membrane that undergoes many transformations during its life cycle. It is resistant to environmental stress which able to survive outside the host however it requires host cellular machinery to complete its replication thus, life cycle of this bacterium is divided between elementary body that infects hosts but cannot replicate and reticulate body that replicates yet cannot able to cause infections.

Chlamydophila psittaci infects mucosal epithelial cells and macrophages of the respiratory tract wherein the bacterium localized in the epithelial cells of most organs, gastrointestinal tract and conjunctiva. Its potential host includes domesticated poultry, cattle, pigs, sheep, horses and feral birds.

Chlamydophila psittaci implicated in systemic infectious disease psittacosis in avian species where it is present in nasal secretions, feces and feathers of infected birds transmitted to human via inhalation of dust and contact or ingestion from contaminated bird which can be treated through antimicrobial therapy like doxycycline, tetracycline, erythromycin and sulfonamides. Symptoms manifested includes cough, dyspnea, fever, epistaxis, severe headache and pneumonia.

Former name: Chlamydia psittaci

Scientific classification:

Kingdom: Bacteria
Phylum: Chlamydiae
Order: Chlamydiales
Family: Chlamydiaceae
Genus: Chlamydophila
Species: Chlamydophila psittaci

See also: