STI & HIV Basics

What are STIs?

Sexually transmitted infections (STIs) or sexually transmitted diseases (STDs) can be passed from one person to another person when you have any type of sex — including vaginal, oral (mouth) or anal.

There are many kinds of sexually transmitted infections and more than half of all people will get one at some time in their life.

Sexually transmitted infections often do not cause any symptoms, but left untreated they can cause a lot of health problems, including making you very sick and making you unable to have children.

Some common STIs:

10- to 14-year-olds in Philadelphia are 5 times more likely to have Chlamydia than other teens of the same age in the U.S.

15- to 19-year-olds in Philadelphia are 3 times more likely to have Gonorrhea than other teens of the same age in the U.S.

If you have had sex without using a condom even once, then you are at risk of having a sexually transmitted infection.

Getting tested lets you know if you have an STI so you can get the treatment you need.