Best Practices

HIV and STI Prevention

Risky sexual behavior can lead to serious health consequences. Risky sexual behavior includes sexual intercourse initiated at an early age, unprotected sexual intercourse, sex with multiple partners, inconsistent or absent contraceptive practices and combining sexual activity with other risk behaviors such as use of alcohol or other drugs. Sexually transmitted infections (STIs) are among the health-compromising results of risky sexual activity.

  • There are more than 25 kinds of STIs.
  • Experts estimate that, annually, one-fourth of all teens (about three million) will contract a sexually transmitted infection. These infections include (not in order of frequency): HIV, human papillomavirus (HPV), hepatitis B virus, chlamydia and gonorrhea.
  • Diagnosed STI cases fail to represent the entire picture. For example, AIDS is the ninth leading cause of death for youth aged 15-25, and given the lag time between infection and onset of symptoms, most infections in this age group were probably the result of unprotected teenage sexual activity.
  • In the United States, rates of HIV and other sexually transmitted infections are disproportionately high among youth of color, particularly young African American and Latina women, when compared to white, non-Hispanic youth.


In Colorado, teens ages 15-19 have some of the highest age-specific rates of gonorrhea and chlamydia.

  • In 2000, the Colorado rate for gonorrhea was 71 per 100,000 persons. For teens ages 15-19 the rate was 230.8 per 100,000, an increase of 11 percent from 1999. The rate for younger teens, though much lower, increased by 16 percent over the same time period.
  • In 2000, female teens ages 15-19 had the second highest actual number of reported chlamydia cases (rate 62.5 per 100,000 persons). The rate for these girls increased by more than 10 percent from 1999, and the rate for younger females ages 10-14 increased by 30 percent during this same time period.


Background Documents


Evidence-Based Programs

Recommended Strategies

Related Colorado Programs