[A family outbreak of Chlamydia psittaci infection].

A family outbreak (3 cases) of Chlamydia psittaci infection was reported. The first case, a 56-year-old man was admitted with fever and general fatigue. Chest X-ray film revealed a consolidation in the right lower lung. One month before admission he had purchased 2 parakeets (chick) and one parakeet died. On learning of his history of contact with the chick, psittacosis was suspected. After administration of fixation (CF) antibody titer against chlamydia rose to 1:128 and IgA titer against Chlamydia psittaci by microimmunofluorescence antibody technique (MAF) rose to 1:128 in 21 days after admission. The second case, the wife of the first, a 53-year-old woman had a fever and a cough about two weeks before the admission of the first case. At the time of her husband was admitted, she attended the outpatient department. The chest CT X-ray film showed a ground glass appearance in both lower lung fields. The third case, the daughter of the first, didn't have any signs. Chest X-ray film was normal. But IgM titer against Chlamydia psittaci by MAF rose to 1:16 and IgA titer against Chlamydia psittaci by MAF rose to 1:128. This case was considered as inapparent infection.