Chlamydiosis, also called “Psittacosis” or “Parrot Fever”, is a common disease of birds. It can occur in any bird but is especially common in cockatiels, Amazon parrots, and budgerigars (often referred to incorrectly as parakeets.) The disease can cause chronic infections, asymptomatic infections, or sudden death. The disease can also be transmitted to people. It is not associated with the venereal chlamydia that affects people.
What causes chlamydiosis?
Chlamydiosis is caused by an organism called chlamydia psittici. This organism is similar to a virus or bacteria but is different enough to be classified within its own special group. Like a virus, but unlike many bacteria, it lives right inside the cells of the bird, which makes it difficult to kill with treatment.
What are some common signs of chlamydiosis in birds?
Chlamydiosis can cause many different signs, and therefore should be suspected in any sick bird. Commonly, chlamydiosis causes chronic respiratory (sneezing, runny eyes or nose) or gastrointestinal (change in droppings) signs. Classically, chlamydiosis causes lime green or yellow feces and urates (the normally solid white part of the droppings) due to chlamydial infection of the liver. However, this is not seen all the time and other diseases can also cause these discolored droppings. Birds can also carry Chlamydiosis asymptomatically, which means they carry the infection, spread it to other birds (and people) but are not sick themselves. This is a good reason for testing all birds for chlamydiosis.
How is chlamydiosis diagnosed?
Several tests are available for diagnosing chlamydiosis. Blood tests can usually tell if your bird is infected even if it is not sick. Sick birds can have their feces checked for the organism as well; however, this test will be negative if the bird is infected but not shedding the organism. As a rule, most healthy birds are checked by one of the available blood tests. In sick birds, faster results can be obtained by checking the feces. Finally, special tests can be performed on the liver, spleen, heart, and air sacs of birds that have died to check for a chlamydial performed infection.
How is chlamydiosis treated?
Treatment is usually with oral injectable doxycycline. Since the doxycycline only kills the chlamydia when they are active and dividing, and the chlamydia often cease being active for a period of time, the drug must be used for a minimum of 45 days. Since doxycycline often predisposes birds to yeast infections, your bird should also take an anti-yeast drug called nystatin during the treatment. After the 45-day treatment, the bird must be retested for chlamydiosis to make sure the treatment was effective.