Summary:
- A sexually transmitted infection (STI) is an infection that spreads through sexual contact.
- STIs are caused by pathogens, a living thing or virus that causes infection.
- The only way to avoid the risk of STIs is to practice abstinence from sexual activity.
- Only some STIs can be cured with medicine; other STIs cannot be cured.
- Rates of chlamydia among U.S. females in 2006 are shown below.
- Rates were much higher in teens and young women than in other age groups.