Quick Answer

The most common STIs in the U.S. by annual new infections: HPV (~13 million), trichomoniasis (~2 million), chlamydia (~1.6 million reported), herpes (~500,000-720,000), gonorrhea (~600,000 reported), HIV (~31,800 estimated), and syphilis (~210,000). HPV is by far the most common, infecting nearly all sexually active people at some point.

  • HPV: so common that the CDC says 'nearly all sexually active men and women get it at some point.'
  • Herpes: ~1 in 6 adults has HSV-2; ~50%-80% of adults have HSV-1 (oral herpes).
  • Chlamydia: highest rates in women aged 15-24.
  • HIV: ~1.2 million Americans living with HIV; ~31,800 new infections per year.

Context Most Pages Skip

The ranking surprises people because prevalence does not match perceived severity. The most common STIs (HPV, herpes) are the ones people worry about least, while the rarer ones (HIV, syphilis) attract most anxiety.

What common means

If you are sexually active, you have statistically encountered HPV. You have a ~1 in 6 chance of having HSV-2. These are normal, not exceptional. The goal is not to avoid them entirely but to manage them.

⚕️ This page is educational and does not replace advice from a licensed clinician. If you may have been exposed to an STI, get tested — most infections are manageable, and many are fully curable.

Sources & Further Reading

Figures reflect CDC surveillance and WHO estimates; they are population statistics, not personal risk predictions.