What are sexually transmitted infections? 

— Sexually transmitted infections, often called STIs, are infections you can catch during sex. They are also called sexually transmitted diseases, or STDs. Some STIs are caused by bacteria, and others are caused by viruses.

The most common STIs include:

Many of these infections can be transmitted through any type of sex. That includes not just penis-in-vagina or penis-in-anus sex, but also oral sex and other types of sex play. HIV and hepatitis can be transmitted in other ways, too, such as exposure to body fluids.

What is STI screening?

STI screening includes a series of tests that doctors use to find out if a person has any STIs. STIs often don't cause any symptoms. People can have STIs and not know it. That's what makes screening so important.

Doctors recommend that people who are at risk for STIs be screened even if they have no symptoms and feel fine. For example, you could be at risk for Chlamydia if you had unprotected sex with a new partner. Screening for Chlamydia will alert your doctor that you have this infection. Treatment will prevent the infection from getting worse and keep you from infecting other people.

There are different types of tests that screen for different infections. Many STIs can be found through a blood or urine test. If you decide to be screened for STIs, your doctor or nurse can work with you to figure out which specific tests you need.

What symptoms should I watch for? 

In general, watch out for any genital itching, burning, sores, or discharge. But be aware that many STIs do not cause any symptoms. The best way to know for sure if you have an STI is to be screened.

What if I have an STI? 

If you have an STI, you will need treatment. The right treatment will depend on the type of STI you have. Treatment might include antibiotics or medicines called antivirals, which fight viruses. Treatment will cure your infection or keep it from getting worse. It will also reduce the chances that you spread your infection to others. 

If you do have an infection, you might need to tell the people you could have infected. Your doctor or nurse can help you figure out which partners you need to tell based on when you last had sex with them.