Which bacterium causes chlamydia?
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sexually transmitted disease
Scanning electron micrograph of the spirochete Treponema pallidum attached to testicular cell membranes.
The sexually transmitted disease known as chlamydia is caused by the bacterium Chlamydia trachomatis.1
This bacterium is a member of the genus Chlamydia, which consists of parasitic microorganisms that grow only within the tissue cells of an infected host. While C. trachomatis is responsible for the sexually transmitted infection characterized by conditions such as nongonococcal urethritis and pelvic inflammatory disease, different strains of the same species can also cause other conditions, including trachoma and lymphogranuloma venereum.12