Psittacosis is a disease caused by the bacterium Chlamydia psittaci.
It is also called Ornithosis, Parrot Fever or avian chlamydiosis, and it occurs worldwide. Birds are the reservoir host and may be obviously sick or appear healthy, but can be carriers of the infectious organism. The bacteria are inhaled from dried droppings, secretions and feather dust from infected birds. Birds may shed the organism intermittently or even continuously for months. The incubation period for humans is 1 to 4 weeks.