Todayโs path rounds are on ๐ฉ๐ฌ๐ข๐ญ๐ญ๐๐๐จ๐ฌ๐ข๐ฌ!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ฌ๐ข๐ญ๐ญ๐๐๐จ๐ฌ๐ข๐ฌ is a bacterial infection caused by ๐๐ก๐ฅ๐๐ฆ๐ฒ๐๐ข๐ ๐ฉ๐ฌ๐ข๐ญ๐ญ๐๐๐ข. โPsittaciโ means parrot, which gives you a clue about what species this disease affects!
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
We see this condition primarily in parrots, however it has been identified in over 450 bird species. It is also a ๐ณ๐จ๐จ๐ง๐จ๐ญ๐ข๐ ๐๐ข๐ฌ๐๐๐ฌ๐ (can spread to humans). In people, this disease is called ๐ฉ๐๐ซ๐ซ๐จ๐ญ ๐๐๐ฏ๐๐ซ.
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
Chlamydia is shed in the nasal discharge and feces of infected animals, which contaminates the environment with the ๐๐ฅ๐๐ฆ๐๐ง๐ญ๐๐ซ๐ฒ ๐๐จ๐ซ๐ฆ of the bacteria. This form easily survives in the environment, and can stay infectious for several months. Animals will inhale or ingest this form of the bacteria, and the elementary bodies will attach to lining of the respiratory tract or intestine. The elementary body is then eaten by ๐ฆ๐๐๐ซ๐จ๐ฉ๐ก๐๐ ๐๐ฌ, the bodyโs major clean up cell, and transforms into a ๐ซ๐๐ญ๐ข๐๐ฎ๐ฅ๐๐ญ๐ ๐๐จ๐๐ฒ that is capable of making new elementary bodies. Once enough elementary bodies are made, the macrophage is split open to release more bacteria into the bloodstream or body secretions.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Psittacosis makes the birds quite sick, with fever, weakness, weight loss and nasal discharge. These birds will develop ๐๐ข๐ซ ๐ฌ๐๐๐๐ฎ๐ฅ๐ข๐ญ๐ข๐ฌ (bacterial infection of their air sacs), pneumonia and ๐ก๐๐ฉ๐๐ญ๐ข๐ ๐ง๐๐๐ซ๐จ๐ฌ๐ข๐ฌ (death of liver cells). In some cases, the infection can be severe enough to cause death in these birds.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
Diagnosis is usually made through identifying the bacteria via ๐๐๐, which identifies the bacteriaโs DNA directly. Usually, this test is conducted on a swab of the ๐๐ก๐จ๐๐ง๐, essentially the larynx of a bird. Necropsy findings may also be helpful in acutely sick animals.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
Whether or not treatment is allowed for these birds depends on local government regulations, as psittacosis is considered to be a ๐ซ๐๐ฉ๐จ๐ซ๐ญ๐๐๐ฅ๐ ๐๐ข๐ฌ๐๐๐ฌ๐. This means there are strict procedures that must be followed if the disease is identified, which may include depopulating all affected birds. If treatment is permitted, ๐ญ๐๐ญ๐ซ๐๐๐ฒ๐๐ฅ๐ข๐ง๐ antibiotics can be effective if given over a very long period of time.
๐๐ก๐จ๐ญ๐จ๐ฌ
1) A parrot with green feces, a characteristic sign of psittacosis.
2) An example of air sacculitis at the top of the image. Normally the air sac linings are clear, not white!
3-5) Enlarged livers from psittacosis.
6) Purple dit-dot Chlamydia within a macrophage of a parrot (middle of image). Fun fact: red blood cells in parrots have ๐ง๐ฎ๐๐ฅ๐๐ข (rod-shaped blue things)!
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Van Wettere AJ. Avian chlamydiosis. Merck Veterinary Manual 2020.
Photos 1-6 ยฉ Noahโs Arkive contributors McGavin, Lowenstine, Maddux, Harrington, Uzal licensed under CC BY-SA 4.0.
