What symptoms are seen in birds infected with Ornithosis?

Birds infected with Ornithosis, which is caused by the bacterium Chlamydia psittaci, commonly exhibit respiratory distress as a primary symptom. This disease often leads to inflammation of the respiratory tract, presenting signs such as difficulty breathing, coughing, and nasal discharge. These respiratory symptoms result from the infection affecting the bird's lungs and air sacs, making them susceptible to pneumonia and other respiratory complications.

Flu-like symptoms may appear in humans who contract the infection, but they are not typical in the avian species. Skin irritations and complete lethargy can also occur in various diseases affecting birds, but they are not specific indicators of Ornithosis. Therefore, respiratory distress is the hallmark symptom of this disease in birds, making it the most accurate choice in this context.