The National Association of State Public Health Veterinarians (NASPHV) has put together an excellent overview of the diseases caused by infection with Chlamydophila psittaci (formerly Chlamydia psittaci) bacteria.
When humans are infected with C. psittaci, the disease is called psittacosis, parrot fever, or ornithosis, which is often associated with pneumonia or other potentially serious illnesses. People are generally exposed to C. psittaci bacteria through contact with pet birds – typically cockatiels, parakeets, parrots, and macaws, although other species can also be involved.
Psittacosis is not a common disease in people – the Centers for Disease Control reports only 66 cases from 2005 to 2009 – but every bird owner should be aware of it. It is quite likely that many cases of psittacosis are not reported to appropriate regulatory agencies, particularly when the symptoms are mild.
Infections in Birds
C. psittaci bacteria are shed in the feces and nasal secretions of infected birds. The organisms can survive for months in the environment if protected by feces or litter. When birds become sick from a C. psittaci infection (also known as avian chlamydiosis), they can have a variety of clinical signs, including:
- loss of appetite
- ruffled feathers
- discharge from the eyes and nose
- weight loss
However, many infected birds do not develop any symptoms but are still capable of transmitting the disease to other birds or people.
Treatment and Prevention
Doxycycline is the drug of choice for avian chlamydiosis, but treatment can be challenging. Affected birds may not eat or drink well, so orally dosed or injectable pet medications may be necessary at the offset. Once a bird’s appetite improves, doxycycline can be added to its food or drinking water. Unfortunately, standard protocols may not completely eliminate the bacteria, and even if a bird’s overall condition returns to normal, these animals still could pose a risk to the people and birds that interact with them.
For more information about avian chlamydiosis and psittacosis in people, take a look at the NASPHV Compendium. It includes recommendations for treatment options, testing methods, and how to prevent and control the spread of the disease through the use of protective clothing, screening, quarantine, appropriate disinfectants, and proper husbandry.