Confirmed case of avian chlamydiosis in Snohomish County
One confirmed case of avian chlamydiosis has been found in a bird that had been boarded at “Wings of the World” in Bothell. That bird has died. Another bird in the same home which has also been boarded was exhibiting signs of avian chlamydiosis and was treated. All other birds in that household were treated prophylactically. Notification is being made to all bird owners that have purchased or boarded a bird at that facility since July 2, or attended their recent Customer Appreciation Day on August 12, encouraging them to watch for symptoms in both birds and humans.
Sometimes referred to as psittacosis or “parrot fever,” avian chlamydiosis is typically found in cockatiels, parakeets, parrots and macaws. Healthy looking birds can be infected and shed the bacteria when stressed, causing infection to other species of birds housed in the same environment, like finches, canaries and doves.
Avian chlamydiosis can be transmitted from birds to humans, causing a bacterial infection known as psittacosis. It mimics symptoms of the flu, including fever and chills, headache, muscle pain, and a dry cough. More severe illness can affect pregnant women and the elderly. Person-to-person transmission is possible but thought to be rare. Psittacosis is also rare in Washington, with less than a dozen cases reported over the last 20 years.
If you have patients reporting symptoms similar to influenza or pneumonia, please determine whether a pet bird is kept in the home. Clinical diagnosis and intent-to-treat is based on a compatible clinical syndrome in the context of exposure to a psittacine bird and reasonable exclusion of other etiologies (e.g., influenza, bronchitis, community acquired pneumonia, etc.). Plain chest radiography is abnormal in about 80% of cases. Lobar infiltrates predominate, but multi-lobar or migrating abnormalities have been reported. Pleural effusions can occur, but are rare. CT scanning often shows nodular airspace disease and ground glass opacities. Laboratory confirmation is typically via serology, submitting paired specimens collected two weeks apart and looking for a four-fold rise in titer. Complement fixation is the most widely available serologic method but microimmunofluorescence is preferred where available. DNA testing is still being researched and culture is discouraged due to the high risk of transmission to laboratory personnel for C. psittaci isolates. Empiric treatment should not await laboratory confirmation, especially if the patient is ill.
The recommended treatment for adults is doxycycline 100mg po bid continuing for 10-14 days after initial improvement. Toxic appearing patients should be hospitalized and treated with intravenous doxycycline until improvement occurs. In children (and in adults with contraindications to doxycyline), macrolides (e.g., azithromycin) are the preferred agent. Alternatives for patients with contraindications to these agents include rifampin, chloramphenicol, or fluoroquinolones; seek infectious diseases consultation in these circumstances.
For additional reporting information, please visit www.doh.wa.gov/ForPublicHealthandHealthcareProviders/NotifiableConditions/Psittacosis
Dr Christopher Spitters, MD
Interim Health Officer, Snohomish Health District