What is the most common bacterial sexually transmitted infection in the US?

Chlamydia is recognized as the most common bacterial sexually transmitted infection (STI) in the United States. This infection is caused by the bacterium Chlamydia trachomatis and affects both men and women, often leading to asymptomatic cases, especially in women. As a result, many individuals may be unaware they are infected, which contributes to its high prevalence.

Furthermore, the Centers for Disease Control and Prevention (CDC) routinely reports chlamydia as the STI with the largest number of reported cases annually. Detection and treatment are crucial since untreated chlamydia can lead to serious complications, such as pelvic inflammatory disease (PID) in women, which can cause infertility and other severe reproductive health issues. Regular screenings in sexually active populations, particularly among young women, are vital for controlling the spread of this infection.

In contrast, while gonorrhea is also common and a significant public health concern, its incidence is lower than that of chlamydia. Syphilis and trichomoniasis, although relevant STIs, do not match the prevalence of chlamydia in the population. This establishes chlamydia as the leading bacterial STI in the U.S.