It’s a question that’s been asked time and time again — can you get an STI from kissing? Despite what many people think, the answer isn’t “no.”

While it’s important to remember that getting an STI is incredibly unlikely, it’s not impossible. But what may surprise you, even more, is the way you can get an STI from kissing. Hint: it’s not through saliva. While saliva is a bodily fluid, not that much of it is passed during even the most intense makeout session.

So in theory, how could one get an STI just through kissing? The answer is usually through open sores.

Herpes

Herpes is the most common STI you can get by kissing because the virus can spread through skin to skin contact. Furthermore, a person doesn’t need to have an open sore for you to catch the virus — though that does increase your chances. Even if someone with herpes doesn’t have any physical signs of the disease at the time of your kiss, it can still be transmitted.

Hepatitis B

Hepatitis B can also be spread through open sores and there have even been a few cases in which it was transmitted via saliva. The most common way to contract hep B is by kissing after sexual activity, particularly activity that involves oral sex.

Syphilis

For syphilis to pass from one person to another, the person not infected with syphilis would have to have an open cut or sore inside their mouth. So long as they don’t have an open wound, you can’t transmit syphilis through saliva alone.

Again, it’s very unlikely that you’ll catch an STI through strictly kissing, but it’s important to be aware of the fact that there is technically a possibility of it happening. Therefore, you should do everything possible to keep yourself and your partner safe!