Infectious agent: Chlamydia trachomatis
Description of illness: Chlamydia is the most commonly reported STD in the United States. Chlamydia affects both women and men, is most common among people 24 years of age and younger, and is frequently asymptomatic. Chlamydial infection can also exist in a person’s oropharynx or rectum. Effective treatment for chlamydia exists. Without early detection and treatment, chlamydia can cause permanent damage to a woman’s reproductive system, which can lead to pelvic infections, ectopic pregnancy, and even infertility. All sexually active women aged 24 years and younger should be screened for chlamydia annually. Additionally, screening should be considered for men who have sex with men as well as older women with additional risk factors (more than one sex partner, or a sex partner with an STD).