Diagnosis, Treatment, and Prevention
Diagnosis of psittacosis can be difficult. Laboratories use several methods to detect Chlamydia psittaci infection. Some tests are only available in specialized laboratories. See the table below for advantages and disadvantages of different methods for diagnosing psittacosis. Laboratories typically run tests on sputum specimens or swabs of the nasopharynx and oropharynx or serum, depending on the method used. In severe cases, other specimen types may be used. When additional or specialized testing is necessary, local or state public health laboratories may be able to either provide diagnostic support or forward specimens to CDC. See CDC’s Test Directory for additional information.
Advantages and disadvantages of select C. psittaci diagnostic methods
|Serologic test (e.g., complement fixation, microimmunofluorescent antibody test)||
|Real-time polymerase chain reaction (PCR)1||
Chlamydia psittaci are sensitive to both macrolides and tetracyclines. However, tetracyclines are the drugs of choice, unless contraindicated as they are in children, due to reported macrolide failures.
Patient isolation and prophylaxis of contacts are usually not indicated, as person-to-person transmission of C. psittaci is rare.
Most states require clinicians to report cases of psittacosis in humans to the appropriate health authorities. Timely diagnosis and reporting may aid in identifying the source of the infection and controlling the spread of disease.
Educate patients about the importance of handling birds and cleaning bird cages safely. Refer birds suspected as the source of human infection to veterinarians for evaluation and treatment.
- Balsamo G, Maxted AM, Midla JW, et al. Compendium of measures to control Chlamydia psittaci infection among humans (psittacosis) and pet birds (avian chlamydosis), 2017Cdc-pdfExternal. J Avian Med Surg. 2017;31(3):262–82.
- Chlamydophila psittaci: Pathogen safety data sheet — infectious substancesExternal, Public Health Agency of Canada, April 2013.
- Mitchell SL, Wolff BJ, Thacker WL, et al. Genotyping of Chlamydophila psittaci by real-time PCR and high-resolution melt analysisExternal. J Clin Microbiol. 2009;47(1):175–81.
- Wolff BJ, Morrison SS, Pesti D, et al. Chlamydia psittaci comparative genomics reveals intraspecies variations in the putative outer membrane and type III secretion system genesExternal. Microbiology. 2015;161(7):1378–91.
- Case report forms and other resourcesExternal are available from the National Association of State Public Health Veterinarians.
1 The National Notifiable Diseases Surveillance System case definition currently considers an illness with characteristic symptoms and detection of C. psittaci nucleic acid in patient specimen via real-time polymerase chain reaction (PCR) to be a probable, but not confirmed, case.