In Bustle's Sex IDK column, certified sex educator and writer Emma McGowan answers the questions you still have about sex. No topic is off limits, and there's nothing to be embarrassed about. Think of it as the sex ed you should've had. Today's topic: how the most common STIs transmitted.

If you had sex ed in the United States, part of your brain probably thinks that being in the same room with someone else’s naked genitals is going to give you a sexually transmitted infection (STI). And if anything sexual happens in that room, you’re definitely getting infected. Rubbing up on each other? STI. Blow jobs or cunnilingus? STI. Vaginal intercourse? STI and a baby. Butt sex? Definitely STI.

And if that’s how you think about STI transmission, it’s not your fault. Because so much of our sex ed is fear-based and sex-negative, there’s a lot of misinformation about sex out there, particularly when it comes to STIs. And, unfortunately, that's the only sex ed that so many Americans get. So it's time to set the record straight on STI transmission: How it happens and how likely you are to actually get something from your partner(s).

My name is Emma McGowan, and I’m the new sex columnist here at Bustle. I’m an SFSI-endorsed sex educator, but I’ve been an unofficial sex educator since I was a tween, when my two best friends asked me how to give a blow job. I hadn’t actually given a blow job yet, but I didn’t want to give them bad info. So I went to the library, looked it up in books, and then supplemented that knowledge with some early-internet research.

While I admire 13-year-old me’s impulse to give my friends the facts — and giving fact-based information is a value I still hold dear — these days the advice I’m dispensing is much more informed and accurate than the blow job advice I gave back then. I’ve been writing about sex, sexuality, and gender issues online for seven years. As a sex educator, I believe that everyone deserves access to science-based, non-judgmental sex information to help them integrate sex holistically and healthily into their lives.

So let’s talk about STIs. Fear of STIs is very, very common — and extremely overblown. The photos that most of us were shown in high school sex ed make it seem like every STI is going to engulf your genitals, causing them to rot and fall off in pieces like a Halloween zombie dripping to the floor. We’re warned about herpes and HPV and how they never go away. We’re taught that getting HIV is the end our lives, if not the end of the world.

Here’s the reality: Human beings give each other infections. Sometimes those infections are in our sinuses and sometimes those infections are in our junk. Bacterial infections — including gonorrhea, chlamydia, and syphilis — can be cured with a quick bout of antibiotics, just like a sinus infection. Viral infections — including HPV, herpes, and HIV — can’t be cured, but can be treated and managed. And as long as an STI is caught early, the physical symptoms of most STIs are experienced as a minor inconvenience.

There's one important caveat here, though. Just because most infections are a minor inconvenience doesn’t mean all are. Different people’s bodies react differently to viruses and bacteria, so while one person may have a nearly microscopic blemish when they contract herpes, another might have a flare-up that leaves them with weeping wounds for a week. Additionally, some STIs (including chlamydia, gonorrhea, and syphilis) can cause infertility if not treated. So while our attitudes toward STIs are generally blown out of proportion, it’s still a good idea to use condoms to reduce your risk, get tested regularly, and get treated if you get something.

But the emotional element of contracting an STI? That’s a whole other story. So many people — myself included — have stories of feeling devastated when they got an STI diagnosis. That’s because of that aforementioned misinformation and fear, which also breeds stigma about STIs. When we go through life operating on incorrect info (and drenched in shame about sex), we’re bound to freak out more about an STI diagnosis — in ourselves or in a partner — than we are to freak out about a diagnosis of the flu or a sinus infection.

So how likely are you to actually get an STI? First things first: You can’t get an STI if the person you’re having sex with doesn’t have an STI. And I know that sounds obvious, but it’s important to acknowledge, because a lot of people do think that sex without a condom automatically means you’re going to get an STI. Remember that whole incomprehensive sex ed thing? This is that in action.

Also, having sex with a person who is infected with an STI does not automatically mean you’re going to get that STI. It’s very hard to gather good data on rates of transmission for each act of intercourse, but there's plenty of people who don’t get infected after having sex with someone who has an infection. However, having sex multiple times with a person who has an infection absolutely increases the likelihood that you’ll get an infection, too. Also, transmission rates vary based on the type of sex you're having (anal sex, for example, is generally higher risk because there's a greater chance of tearing). And people are more or less contagious at different points in the life cycle of the STI they have, which can also affect transmission rates.

And finally, before we get into the weeds about each STI, I need to say a little bit about health disparities. Unfortunately, STI rates are not the same for every race, gender, or age. There are many, many factors that contribute to why one group may have higher rates than another group. They include, but are not limited to: the physical sex acts they’re likely to engage in, access to health care, access to barrier methods (like condoms), access to sexual education, likelihood of sexual assault, and likelihood of multiple partners. So when you read that men are more likely than women or African Americans are more likely than Latinx people to have a certain STI, please keep in mind that it’s not a judgment on that group, but actually a combination of very complex social factors.

So, here are some of the most common STIs and how they're transmitted.