An illness characterized by fever, chills, headache, photophobia, cough, and myalgia
A clinically compatible case that is epidemiologically linked to a confirmed case or that has supportive serology (e.g., C. psittaci titer of greater than or equal to 32 in one or more serum specimens obtained after onset of symptoms)
A clinically compatible case that is laboratory confirmed
The serologic findings by complement fixation (CF) also may occur as a result of infection with Chlamydia pneumoniae or Chlamydia trachomatis. The MIF might be more specific for infection with C. psittaci, but experience with and availability of this newer test are more limited.