Chlamydia trachomatis is the most commonly reported sexually transmitted infection in the United States; with an estimated 3 to 4 million new infections occurring each year. Almost 80% of chlamydia infections in women and over 50% of chlamydial infections in men are asymptomatic. While the infection can be easily detected and treated, millions of cases go unrecognized.

If left untreated, chlamydia can have severe consequences. In women these infections often result in pelvic inflammatory disease (PID), which can cause infertility, ectopic pregnancy and chronic pelvic pain. Chlamydia can also cause prematurity, eye diseases, and pneumonia in infants born to infected mothers. In men, untreated chlamydia infection can result in urethritis and epididymitis.

It is estimated that up to 40% of women with untreated chlamydial infection will develop PID, and 1 in 5 women with PID become infertile. Moreover, women infected with chlamydia are 3 to 5 times more likely to become infected with HIV, if exposed.

Because of the silent nature of chlamydial infection the key to identifying, treating and controlling the spread of infection is widespread screening of asymptomatic populations at risk for infection.

Gonorrhea

Gonorrhea (Neisseria gonorrheae) is another common sexually transmitted disease; approximately 650,000 new cases of gonorrhea occur in the United States each year.The rates of coinfection for gonorrhea and chlamydia are high (~30-50%). Untreated gonorrhea is a common cause of PID in women and of epididymitis in men. Gonorrhea can also spread to the blood and joints, resulting in a potentially fatal condition. Like chlamydia, gonorrhea is often asymptomatic in women and can only be detected through screening.