Chlamyia pneumoniae (also suggested as Chlamydophila pneumoniae) is a species of chlamydiae bacteria that infects humans and is a major cause of pneumonia. Chlamydia pneumoniae has a complex life cycle and must infect another cell in order to reproduce and thus is classified as an obligate intracellular pathogen. In addition to its role in pneumonia, there is evidence associating Chlamydia pneumoniae with atherosclerosis and with asthma. The full genome sequence for Chlamydia pneumoniae was published in 1999.