Yes, You Can Get Herpes From Oral Sex — Here's How

Before I was a certified sex educator, a good friend of mine got genital herpes in high school — from herself. She had a cold sore on her mouth, gave her boyfriend a blow job, and then had intercourse without a condom. She didn’t know (and I didn’t know until she told me what happened) that you can get genital herpes from oral sex. Yup, spoiler alert — you can absolutely get genital herpes from oral sex. But let’s take a look at how, exactly, that happens.

First of all, there are two types of herpes virus: HSV1 and HSV2. HSV1 is the virus that usually causes oral herpes (aka cold sores), while HSV2 usually causes genital herpes. Under a microscope, the two viruses look almost identical. About 50 percent of their DNA is the same, as well as 85 percent of their genetic material. The sores that sometimes show up as a result of an infection by either virus look identical, so the only way to tell which one a person has is by taking a strain-specific blood test. (However, those tests aren't super accurate and the CDC tends to recommend people don't get them, FWIW.)

Practically, there’s one major difference between the two strains of HSV and that’s where it hangs out in your body. HSV1 usually chills in the cells in the base of the neck, which is why it presents itself as a sores around the mouth. HSV2 usually chills in the base of the spine, which is why sores show up around the genitals, anus, upper thighs, and butt.

How Is Herpes Transmitted?

Both HSV1 and HSV2 are spread by skin-to-skin contact. You can get them from touching, kissing, oral sex, vaginal sex, and anal sex with someone who’s infectious.

According to the World Health Organization (WHO), HSV1 is usually transmitted via mouth-to-mouth contact. So, for example, if you kissed someone with HSV1 and they were currently infectious, you could get the virus on your mouth. Same goes for sharing forks and spoons or even just touching skin-to-skin with someone who’s infectious. HSV1 can also be transmitted from mouth to genitals, as my friend found out in high school.

HSV2, on the other hand, is primarily spread from genital-to-genital contact, but it can also be spread orally. This is the one that people are generally referring to when they say “herpes” but, remember — either virus can cause genital herpes.

Both viruses can cause sores — and both can lie completely dormant with no symptoms at all, for years. Some people can spend their entire life with one or both herpes viruses lying dormant and not even know that they’re there. If you don’t show symptoms, the only way to know whether or not the virus is in your body is via a blood test.

How Can You Prevent Herpes Transmission?

So if herpes is just hanging out in some people’s bodies, with no noticeable symptoms, how can you prevent getting or giving it? Well, the only surefire way to never get HSV1 or HSV2 is to never kiss or touch another person. Also, never share utensils or take a bite of someone’s ice cream or borrow their chapstick or stand within spittle distance if they’re someone who tends to spit when they talk. (Seems a little over the top, doesn’t it?)

However, if you think you don’t have either strain of the virus yet (and the chances of that are low — an estimated 90 percent of adults have been exposed to HSV1 at some point in their lives), you can lower your risk of contracting HSV1 by limiting your exposure to other people’s saliva, genital secretions, and skin. In plain English, that means no kissing, no sharing of utensils or chapsticks or ice cream cones. And condoms provide some protection from HSV2 transmission because they cover up the penis, but if the virus is actively shedding on any other part of the genitals, it can still be transmitted from skin-to-skin contact.

If your partner already has a herpes diagnosis, however, they can talk to their doctor about taking antiviral medications that will suppress the virus and keep them from shedding it. That means they won’t be able to spread it.

How Big Of A Deal Is A Herpes Infection?

It’s pretty common to freak out after a diagnosis of genital herpes, but the stigma around the infection has more to do with our cultural attitudes about sex than it has to do with the reality of the illness. Sure, for some people herpes can be terrible. (For example, people with compromised immune systems often have more outbreaks than people whose immune systems are healthy.) But for the majority of people, herpes presents as a minor-to-mid level annoyance. They might have one outbreak and then show no symptoms for years or they might even show no symptoms at all.

And most people know HSV1 as “cold sores” or “fever blisters.” A lot of people contract the virus in childhood, before they can even understand WTF a viral infection is. Because sores from HSV1 usually show up around the mouth and because it’s so common in children, it’s a pretty low-stigma illness. Sure, it doesn’t look very pretty if sores show up. But most people aren’t crippled by a diagnosis of “cold sores.”

But, as you just learned, the two viruses are pretty much the same — and they both can show up on your genitals. You can get genital herpes from having oral sex with someone who is shedding the virus on or near their mouth. If that happens, then the exact same thing that caused the cold sore is causing genital sores.

So if you think cold sores are NBD, it’s worth thinking about your attitudes about genital herpes. Sure, it’s annoying. Outbreaks can be painful and you should avoid sexual contact if you’re having one on your genitals or on your mouth. But human beings spread illnesses and germs all the time. The herpes viruses are just two more ways we do that.