Objective  To describe epidemiological characteristics of an epidemic of Chlamydia psittaci pneumonia, and provide reference for research of psittacosis prevention and control.

  Methods  Epidemiological investigation of the case and people with co-exposure were conducted by telephone and field interview. And the samples of people, birds and environment were collected for pathogen detection.

  Results  In this epidemic, 1 case and 2 asymptomatic carriers were detected. A 71-year-old woman was admitted to hospital due to fever and critical condition of chest CT showing double pneumonia. The results of metagenomic next-generation sequencing by using the blood and sputum samples of the case indicated the infection of Chlamydia psittaci. At the same time, the respiratory samples were positive for Chlamydia psittaci nucleic acid and the blood sample was antibody positive. In addition, two family members of the case showed no symptoms, but were tested positive for Chlamydia psittaci antibody. The epidemiological investigation indicated that birds, such as the black parrot and the munia, had been raised in the family for more than two years. Recently, new parrots were introduced into the family, and three birds died later. Also, the birds’ cages and other environmental samples at the case’s home were positive for Chlamydia psittaci nucleic acid.

  Conclusion  Chlamydia psittaci pneumonia can be severe in some populations and cause epidemic in families. It is necessary to strengthen health education about this disease, improve the awareness of clinical characteristics of the disease for the early diagnosis and treatment.