The Chlamydia are obligate intracellular parasites. In other words, oculourogenital infections. C. psittaci produces systemic diseases including psittacosis, ornithosis and pneumonitis.
Elementary bodies attach and are internalized by susceptible host cells.
Over a 24 hour period, these reticulate bodies divide and begin to reorganize back into elementary bodies. About 48-72 hours after infection, the cell is lysed and numerous infectious elementary bodies are released. The pathogenic mechanisms employed by Chlamydia are not well understood. C. trachomatis is spread via the fingers to the urogenital area and vis versa . In contrast, C. psittaci is acquired from infected birds, usually via the respiratory route.