Psittacosis (ornithosis, parrot fever, chlamydiosis)

Updated: August 2017

What is psittacosis?

Psittacosis is an infectious disease usually spread to humans from infected birds in the parrot family. Birds in the parrot family, or psittacines, include parrots, macaws, budgerigars (parakeets or budgies), and cockatiels. Domestic turkeys and pigeons have also infected people. Bacteria called Chlamydia psittaci cause the disease.

Who gets psittacosis?

Because birds in the parrot family spread this disease, it is occasionally found in pet store workers, bird owners, zoo employees, and veterinarians. It may also rarely be found in farmers and slaughterhouse workers who process poultry (turkeys, chickens, and ducks), especially turkeys. It is a rare disease in the U.S. with fewer than 10 cases reported per year since 2010. Because of modern laws that regulate the pet bird trade, psittacosis is less common than it used to be.

How is psittacosis spread?

Psittacosis is usually spread by inhaling dust from dried droppings from birdcages or by handling infected birds in slaughterhouses. Waste material in the birdcage may stay infectious for weeks.

What are the symptoms of psittacosis and when do they appear?

In humans, the symptoms are fever, headache, chills, muscle pains, cough, and sometimes breathing difficulty or pneumonia. If left untreated, the disease can be severe, and even result in death, especially in older people. Some people may only experience mild flu-like illness, or have no illness at all. In birds, the symptoms include poor appetite, ruffled appearance, eye or nose discharge, green or yellow-green droppings, and diarrhea (loose droppings). Occasionally, birds may die from the disease. Some birds may shed the bacteria while exhibiting only mild or no symptoms.

The time from when a person is exposed until symptoms appear, typically ranges from 5 to 19 days, but longer periods have been reported.

How is psittacosis diagnosed?

Laboratory tests on blood or respiratory secretions or other tissues are used to identify the presence of the bacteria in humans and birds.

Does past infection with psittacosis make a person immune?

Infection does not provide permanent immunity to this disease.

What is the treatment for psittacosis?

Antibiotics such as tetracycline or doxycycline are often prescribed for treating infected people.

What can be done to prevent the spread of psittacosis?

If birds are kept as pets, clean the cage often so that droppings do not accumulate or dry up, creating particles that become airborne. Test and/or separate birds that have been in contact with other birds outside the home to reduce the chance of bird-to-bird spread. Only buy healthy, U.S.-bred birds from reputable sources. Talk with a veterinarian about all bird illnesses. If a person develops signs of psittacosis, consult with a physician and mention any bird contact to the physician.