How to Prevent STIs

Key points

  • This page includes information about prevention, testing for sexually transmitted infections (STIs) as well as related resources.
  • Safer sex practices can protect you from STIs.
  • Testing is important to prevent the spread of STIs.
a hand blocking the falling of tiles to prevent others from falling - metaphor for prevention


What are STIs?

An STI is a virus, bacteria, fungus, or parasite people can get through sexual contact. Sexually transmitted diseases (STDs) develop as a result of an STI. STD implies that the infection has led to some symptom of disease.

How STIs spread

STIs pass from one person to another through oral, anal, and vaginal sex, as well as genital skin-to-skin contact.

Risk factors

Several behaviors can increase your risk:

  • Having anal, vaginal, or oral sex without a condom
  • Having multiple sex partners
  • Having anonymous sex partners
  • Having sex while under the influence of drugs or alcohol can lower inhibitions and result in greater sexual risk-taking


Most STIs have no signs or symptoms. You or your partner could be positive and not know it. The only way to know your status is to get tested.

Prevention steps and strategies

Steps to reduce your STI exposure:

  • Abstaining from vaginal, anal, or oral sex. This is the only way to completely avoid STIs.
  • Getting vaccinated. Vaccines are recommended for some people to prevent hepatitis B and HPV.
  • Reducing your number of sex partners.
  • Regular testing. You and your partner should get tested and share your results.
  • Being in a mutually monogamous relationship with a partner who has been tested and does not have an STI.

Testing, diagnosis, and treatment

Knowing your STI status is a critical step in prevention. Ask your healthcare provider to test you. Asking is the only way to know if you are receiving the right tests. Make sure your partner asks a healthcare provider about testing as well. Many STIs can be easily diagnosed and treated. If you or your partner have an STI, both of you need treatment at the same time.

Find a STI testing center near you.