Chlamydia

This illustration is the artist's interpretation of an electron micrograph image showing cells infected with Chlamydia. Chlamydia is a common sexually transmitted disease (STD) caused by the bacterium, Chlamydia trachomatis. Symptoms of chlamydia are usually mild or absent but can result in serious complications that cause irreversible damage, including infertility. Chlamydia can also cause discharge from the penis of an infected man.