Psittacosis, parrot fever, is an infectious disease caused by Chlamydophila psittaci, a common pathogen among birds. The clinical course ranges from a mild flu-like illness to severe disease that requires intensive care in humans. We report three cases of severe pneumonia where C. psittaci was unexpectedly detected during routine validation of a new C. psittaci PCR assay. Psittacosis is a notifiable disease in Sweden and national statistics show that 96% of Swedish psittacosis cases were identified in five of the 24 microbiological laboratories available in the country. These five laboratories perform PCR for C. psittaci routinely in panels with other atypical pneumonia agents and/or Legionella, suggesting that psittacosis is an underdiagnosed infection in Sweden.