What is an STI?

An STI, or sexually transmitted infection, is basically any kind of bacterial or viral infection that can be spread through sexual contact.

This doesn't just mean unprotected sex. Some STIs can be passed on through oral sex (kissing, licking or sucking someone's genitals), and some can be passed through sexual touching and skin-to-skin contact.

There are lots of STIs out there and you will probably already have heard of some like chlamydia, gonorrhoea, genital warts, genital herpes, HIV...

Many are on the increase, and all of them can affect anyone. Some don't show up straight after you get infected.

Some can show signs a few days after unprotected sex. Others can go unnoticed for a long period of time. Some don't ever show any symptoms at all.

The good thing about infections is that they're often easy to sort out. But leave them untreated and they may cause serious damage to your long-term health.

Most people talk about STIs (sexually transmitted infections).Others call them STDs (sexually transmitted diseases) or even VD (venereal disease). They're all talking about the same thing - infections that can be caught or passed on during sexual contact with another person.