Animal HealthDiseasesChlamydiosis

Avian Chlamydiosis (Psittacosis)

Avian Chlamydiosis is a disease caused by the bacterium Chlamydophila psittaci, formerly known as Chlamydia psittaci.

The disease occurs worldwide. Chlamydial organisms have been isolated from approximately 100 bird species. The organism is most commonly found in psittacine (parrot-type) birds, especially cockatiels and budgerigars, commonly known as parakeets or budgies. Among caged, nonpsittacine birds, infection with Chlamydiaceae organisms occurs most frequently in pigeons and doves. Avian chlamydiosis is less frequently diagnosed in canaries and finches. Poultry (turkeys and ducks) are also involved in transmission to humans.

In humans, the resulting infection is referred to as psittacosis (also known as parrot fever and ornithosis). In birds, C. psittaci infection is referred to as avian chlamydiosis (AC).

ReportFor commercial poultry operations - Avian Chlamydiosis is a voluntary reportable animal disease. Report confirmed cases to: The National Animal Health Reporting System (NAHRS) at 970-494-7000.

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Department of Livestock
Animal Health Bureau
PO Box 202001
Helena, MT 59620-2001
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