You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Description
Psittacosis is the term given to an infectious disease which is endemic in birds (both psittacines and ornithines) worldwide. In ornithines the disease is called "ornithosis". The infection is transmissible to other species and regularly causes disease in humans, cattle, sheep, pigs, and cats. Occasional infections of dogs have been reported.

Cause
The cause is an infective agent, Chlamydia psittaci ,which is an obligate intracellular bacterium consisting of RNA and DNA..

Signs
Clinical signs depend upon the species involved :

• Birds
  • Infected birds can appear healthy
  • Depression
  • Inappetance
  • Respiratory disease - rapid breathing rate, open mouth breathing/gasping
  • Eye discharge
  • Nose discharge - sneezing
  • Watery green diarrhoea
  • Ruffled feathers
  • Weight loss
  • Sudden death in severe acute forms of the disease
• Cats
  • Conjunctivitis
• Cattle
  • Pneumonia
  • Arthritis
• Dogs
  • Cough 
  • Fever
  • Lameness
• Humans
  • Conjunctivitis
  • Flu-like disease
  • Headache
  • Fever
  • Pneumonia
  • CNS signs
  • Diarrhoea - uncommon
  • Renal failure
  • Death -  mortality rates of up to 20% have been reported
• Pigs
  • Pneumonia
  • Arthritis
• Sheep
  • Abortion (called enzootic abortion)

Spread of infection is through direct contact with secretions from infected animals, or aerosol spread.

Complications
Stress often precipitates the disease in animals which are carrying the organism but which are otherwise healthy. So, capture and transportation of wild parrots commonly causes sufficient stress for them to succumb to the disease. Animals that recover from infection may remain carriers of the organism and can relapse later.

Long term problems
Latent carrier state is common, particularly in birds.