infectious diseases
Chlamydia
Chlamydia psittaci
(See also the Centers for Disease Control and Prevention's [CDC]Psittacosis: For Clinicians and Laboratorians.) C. psittacicauses psittacosis. Strains causing human disease are usually acquired from psittacine birds (eg, parrots), causing a disease characterized by pneumonitis. Patients may have severe headache and abnormal liver blood tests. Psittacosis is a rare infection. Since 2010, typically < 10 cases/year are reported to the CDC (see also the CDC'sPsittacosis). However, psittacosis might be underdiagnosed because mild cases do happen. History of epidemiologic exposure is very important, eg, pet bird owners, veterinarians, and workers in the poultry industry. Outbreaks have occurred among workers who handle turkeys and ducks in poultry processing plants. 