How to Prevent Sexually Transmitted Infections (STIs)

What STIs are

A sexually transmitted infection (STI) is a virus, bacterium, fungus or parasite that people can catch through sexual contact. A sexually transmitted disease (STD) is what develops when an STI leads to symptoms of disease.

How they spread

STIs pass between people through oral, anal and vaginal sex, and through genital skin-to-skin contact.

Risk factors

• anal, vaginal or oral sex without a condom;
• multiple sex partners;
• anonymous sex partners;
• sex under the influence of drugs or alcohol, which can lower inhibitions and lead to riskier sex.

Symptoms

Most STIs cause no signs or symptoms, so you or a partner could be infected without knowing it. The only way to know is to get tested.

Lowering your risk

• Abstinence from vaginal, anal and oral sex is the only way to avoid STIs completely.
• Vaccination against hepatitis B and HPV is recommended for some people.
• Fewer partners lower the risk.
• Regular testing: you and your partner should both be tested and share the results.
• Mutual monogamy with a partner who has been tested and does not have an STI.
• Condoms, used the right way every time.

Testing and treatment

Knowing your STI status is a key step in prevention. Ask your healthcare provider to test you: asking is the only way to be sure you get the right tests, and your partner should ask too. Many STIs are easy to diagnose and treat; if you or your partner has one, you both need treatment at the same time. Find an STI testing centre near you.

Sources

• Centers for Disease Control and Prevention, "How to Prevent STIs." https://www.cdc.gov/sti/prevention/index.html
• A stock photograph is not reproduced here.