Chlamydiosis (psittacosis, parrot fever, ornithosis) is a common disease of birds caused by a bacterial organism called Chlamydia psittaci. Birds with chlamydiosis exhibit a decreased appetite, weight loss, lethargy, diarrhea, nasal or ocular discharge, a fluffed-up appearance, and breathing difficulties. Testing and treatment are discussed. Chlamydiosis is a zoonotic disease, meaning that it can be passed to humans, so all new pet birds should be tested for this disease.

COVID-19 is a viral respiratory disease of humans that was first discovered in late 2019. The illness is caused by the virus SARS-CoV-2, which is a new coronavirus that has not previously been identified in humans. Certain animals can be infected by the COVID-19 virus, but it appears to be infrequent. Dogs and cats seldom show severe clinical illness if infected with COVID-19.