Chlamydophila pneumoniae
（重定向自Chlamydia pneumoniae）
![Micrograph ofChlamydophila (Chlamydia) pneumoniae in an epithelial cell in acute bronchitis: 1 – infected epitheliocyte, 2 – uninfected epitheliocytes, 3 – chlamydial inclusion bodies in cell, 4 – cell nuclei](/Images/godic/202501/04/Chlamydia_pneumoniae4131.jpg")
![Life cycle of Chlamydophila pneumoniae. A — Chlamydophila elementary body. B — Lung cell. 2 — Chlamydophila enters the cell. 3—Elementary body becomes a reticulate body. 4 — Replication. 5 — Reticulate bodies become elementary bodies and are released to infect other cells.](/Images/godic/202501/04/Chlamydophila_pneumoniae_lifecycle-it.svg4131.png")
Chlamydophila pneumoniae is a species of Chlamydophila, an obligate intracellular bacterium that infects humans and is a major cause of pneumonia. It was known as the Taiwan acute respiratory agent (TWAR) from the names of the two original isolates – Taiwan (TW-183) and an acute respiratory isolate designated AR-39. Until recently, it was known as Chlamydia pneumoniae, and that name is used as an alternate in some sources. In some cases, to avoid confusion, both names are given.