How do you catch an STI?

It’s simple. You catch an STI by having sex with an infected partner. Some STIs spread when body fluids get passed on during sex. The body fluids include semen, vaginal fluids, saliva, and blood. Other STIs spread by touching infected areas. It doesn’t matter what kind of sex it is. You can catch an STI if sex involves the mouth (oral sex), vagina (vaginal sex), or anus (anal sex). STIs can sometimes be caught by just direct touching or rubbing. The risks of catching an STI are high if:

• You have more than one sex partner 

• Your partner has sex with other people

• You don’t use latex condoms

What can you do?

To prevent problems now—and in the future—decide if it’s the right time to have sex. It’s OK to wait. Not having sex is the only sure way to prevent STIs.

But if you are having sex ...

• Always use a latex condom during sex. Why latex? When used correctly during sexual intercourse, latex condoms work very well compared with other types of condoms. They are better at reducing—but not eliminating—the risk of the transmission of HIV and other viruses and STI germs. Don't use condoms made of lambskin or natural membranes.

• Limit how many sex partners you have. The more people you have sex with, the higher your risk of catching an STI.

• Stay in control. Don't have sex or put yourself in risky situations if you have been drinking or using drugs. These can affect your judgment. This can make it harder to stay safe.

• Get checked if you think you have an STI or could have been exposed to one. Then you can be treated if you do have an STI.

• Protect yourself against HIV. Consider additional ways that you can prevent picking up HIV. Pre-exposure prophylaxis (PrEP) is medicine taken regularly to lower the risk from future contacts. Post-exposure prophylaxis (PEP) is medicine given after a possible exposure. But PEP must be started as soon as possible after sex and no later than 72 hours after to be effective. Contact your healthcare provider, your school nurse, or campus clinic to find out more about these. Or go to your nearest STI or sexual health clinic. Your local health department and the CDC website will have information as well.

• Tell your partners. It’s important to talk with your partner(s) about STIs and testing. But it is important to feel safe to have this talk. If you’re afraid that your partner might hurt you when you talk about testing, send a text, email, or make a phone call instead of talking face-to-face. Ask for help if you’re not safe. It's also important to talk with your partner(s) and to encourage them be treated. Otherwise they can pass the infection back to you or to others.

• Learn about expedited partner therapy (EPT). If you have been diagnosed with an STI, talk with your provider about EPT. With EPT, you may be given a prescription or medicines to give to your partner without your partner needing to be seen by the provider. EPT is available in many states for some STIs (mainly chlamydia and gonorrhea). State laws vary, so talk with your provider.