Chlamydophila psittaci (Chlamydophila felis)
Chlamydia psittaci is a bacterial pathogen of the conjunctiva and respiratory tract of cats. Transmission is through direct cat-to-cat contact. Serous conjunctivitis is the most common clinical sign. Sneezing or nasal discharge may develop. Clinical signs are evident for 5-10 days after infection and resolve with appropriate antimicrobial therapy. Immunity conferred by vaccination is similar to that conferred by FHV and FCV in that vaccinates are protected from severe clinical disease but not from infection. The frequency of adverse events associated with C. psittaci vaccines is higher and includes lethargy, depression, anorexia, lameness and fever for 7 to 21 days.
Because signs of disease are comparatively mild and respond favourably to treatment, routine vaccination is not recommended. However, vaccination may be considered for cats in multi-cat households, where infections associated with clinical disease have been confirmed. If vaccination is deemed appropriate, annual revaccination is recommended.