I am going to put my recommendations first in the hopes that people will read them before they go down to the comments to complain about me encouraging people to have unprotected sex. In short: I think you should get tested regularly for STIs (every six months if you have multiple sexual partners, less often if you’re monogamous). You should use condoms for anal sex and PIV unless you are in a stable long-term relationship with someone and you have both been tested for STIs. If you have an STI, you should get treated immediately, tell anyone you might have exposed, and disclose to your partners as long as you’re at risk of transmitting STIs.

I would also like to state ahead of time that while some people’s attitudes towards STIs are frankly stupid, people are allowed to refuse to have sex for stupid reasons, and nothing in this post should be taken as condemnation of people’s personal sexual decisions. (It can, however, be taken as condemnation of people spreading STI hysteria to others.)

There are four incurable STIs: herpes, hepatitis, HPV, and HIV/AIDS. I assume we are not going to care about the curable STIs; while gonorrhea is a pain in the dick, regular testing and taking your antibiotics as prescribed fix the problem fairly well.

There is a vaccine for HPV and for hepatitis B; the hepatitis B vaccine also protects against hepatitis D, as hepatitis B must be present for hepatitis D to occur. You probably got the hepatitis B vaccine when you were a kid. If you got vaccinated for HPV, preferably before you had multiple sexual partners, there isn’t a huge amount to worry about; however, many people did not, and they are justified in a slightly higher level of concern about HPV. Regardless, you should get your cervical cancer screenings regularly, because while the HPV vaccine protects against the most common forms of HPV it does not protect against all of them.

Hepatitis C is only rarely sexually transmitted; my sense is that if you don’t make a habit of sleeping with people who share needles when they inject drugs, you don’t have a lot to worry about.

Assuming you are not immunosuppressed, currently pregnant, or otherwise going to have abnormally bad outcomes from contracting herpes, herpes is a ridiculous thing to care about getting. You know that whole thing about how most people who have STIs don’t know they have STIs? 87.4% of people with herpes have no idea they have herpes. But herpes does not have silent symptoms. It’s not like chlamydia, where it’s asymptomatic and you don’t get tested and next thing you know you have pelvic inflammatory disease and you’re infertile. The consequence of herpes is that you get sores on your genitals and they hurt, and evidently for nearly ninety percent of the people who have it the sores matter so little that they don’t even realize they’ve contracted the virus.

And then that twelve percent of people who know they have herpes? Includes people who had one or two serious flareups and never had another one. Includes people whose partner had herpes that flared up all the time but who are asymptomatic themselves. Includes, in short, quite a lot of people for whom herpes is no big deal. Having regular herpes flareups sucks (although there is medication that helps), but only a very small fraction of people who get herpes will have regular flareups.

The primary negative consequence of herpes is having to tell people you have herpes. And the best part is that, statistically, a fair number of the people who stigmatize people with herpes? Have herpes themselves.

Finally, there’s HIV. AIDS is legitimately scary and it is good to take steps to reduce the risk of contracting HIV. People without HIV should get tested regularly for HIV (what ‘regularly’ means depends on their risk factors), use condoms unless in a stable fluid-bonded relationship where both they and their partner have been tested, and refrain from having high-risk sex with HIV-positive people. People with HIV should take their medications and disclose to their partners. (And, of course, not everyone is capable of those things– we need to expand access to sexual health care.)

However, even HIV– which is legitimately scary and which people should avoid– has frankly hysterical aversions to it. For one thing, many people suggest the use of barriers in sex between cis women in order to prevent HIV transmission. There has been exactly one recorded case of confirmed cis-woman-to-cis-woman HIV transmission. (There have been several other cases that could also have been caused by sex with other people or sharing needles.) And, frankly, the lesson of that case is “don’t give unprotected cunnilingus to your HIV-positive girlfriend during her period.” It does not mean that cis lesbians as a whole should be using dental dams with each other.

For another, many people suggest that HIV-negative people should never have sex with HIV-positive people. Many sex acts are extremely unlikely to transmit HIV, including manual sex, oral sex (especially if protected), and using sex toys. Furthermore, people who have an undetectable viral load have an approximately zero risk of transmitting HIV. You are far, far more likely to contract HIV from someone who didn’t get tested for HIV in the last year than you are to contract HIV from an HIV-positive person who adheres faithfully to antiretroviral therapy. And yet many people who refuse to have sex with HIV-positive people with an undetectable viral load do not even ask their partners the last time they got tested!

Why is there so much STI hysteria? Partially, I blame shitty sex education. In America, sex education comes in two forms: abstinence-only and comprehensive. Much abstinence-only sex education is medically inaccurate. Even the medically accurate abstinence-only sex education has little incentive to give a balanced assessment of the risks of particular STIs: they’ll mention that herpes is incurable and easily transmitted without mentioning that it’s a complete nonissue for more than ninety percent of the people that have it; they’ll say that chlamydia can make you infertile without mentioning that it’s easily treated with antibiotics.

Comprehensive sex education is not much better: while it at least acknowledges that people might have premarital sex, it treats condoms as a harm-reduction measure for a regrettable mistake people will make. But nonmarital sex is not the same thing as injecting heroin. Comprehensive sex education completely lacks the idea that nonmarital sex is pleasurable, enriching, valuable, or otherwise a legitimately good thing that people should have. And as long as that’s the case, they can’t teach people to rationally assess the risks and benefits of their sexual practices.

The other reason, I think, is that people are willing to accept a lot more risk with regards to anything that is not sex than they are with regards to sex. Compare the treatment of herpes I and herpes II. The only differences between herpes I and herpes II are that herpes I is more common and that herpes II is more likely to be sexually transmitted. Herpes I is a nonissue– cold sores are a routine, if painful, fact of life that elicit sympathy rather than condemnation; no one would refuse to kiss someone because they once had a cold sore. Herpes II, conversely, is tremendously stigmatized and people regularly turn down sex with people with herpes– even when they haven’t had a flareup in years.

Frankly, this is a product of irrational sex-negativity. Sex is dirty. Therefore, diseases that you get from sex must be super extra dirty. It’s not just a disease like the flu or chicken pox; it’s a Slut Stigmata branded on your genitals. Far too many people have transferred their disgust about promiscuous people to disgust about people who happened to be unlucky. We call people without STIs “clean”. Imagine if we called someone who didn’t have the flu “clean”.

Irrational fear of STIs causes tremendous harm. Many people are afraid to get tested because of what they might discover. Many people miss out on good sex or relationships because of irrational fear– either because they refuse sex with a person with an STI, or because they’ve chosen to have fewer sexual partners than they otherwise would. Many people with STIs live with shame, stigma, and fear.