When Charlie Sheen announced earlier this week on the Today show that he is HIV positive, he added that through antiretroviral treatment, his viral load is now undetectable. “My medical team could only shake their heads as each and every blood test returned levels revealing a state of remission,” he wrote. In going public with his status, Sheen introduced the country at large to the emerging reality of what it means to be HIV positive in 2015.

Dr. Robert Huizenga, Associate Clinical Professor of Medicine, UCLA, who treated Sheen, confirmed Sheen’s statements, and said that Sheen was “absolutely healthy from that vantage.” He added, “Individuals who are optimally treated, who have undetectable viral loads, who responsibly use protection have an incredibly low—it’s incredibly rare to transmit the virus. We can’t say that it’s zero, but it’s a very, very low number.”

Given the amount of ignorance and stigma with which HIV is regarded in our culture, these are big concepts for people to wrap their heads around. Through the years, I’ve written frequently on this topic (starting in 2012, when my thinking was far more fearful, ignorant, and just plain incorrect). Still, I think all of it warrants repeating, and spelling out in the simplest terms possible. Below, I examine what “undetectable” really means, the continuing criminalization of HIV, and what constitutes “safe sex” in 2015.

Is Charlie Sheen, a person living with HIV, really “absolutely healthy?”

If his viral load—the amount of HIV in his blood—is undetectable, then yes.

What does “undetectable” mean?

According to aidsmap: “Undetectable viral load is usually defined as below 50 copies [of HIV’s genetic material]/ml [of blood on one’s system]. Until recently, this was the lowest detectable level for tests most commonly used in routine viral load monitoring. There are now some ultra-sensitive tests that can measure below 20 copies/ml.” What this means, essentially, is that there is such a small amount of HIV in one’s blood that it doesn’t register at all in standard tests.

So he’s cured?

No. He’s treated, and must continue to be so. There is evidence suggesting that the life expectancy of people living with HIV who are treated is almost the same as those who are negative.

What is this treatment?

It’s called antiretroviral therapy, and, to massively simplify things, it essentially staves off the development of AIDS (and all of its ensuing complications like pneumocystis pneumonia and Kaposi’s sarcoma). When the first cocktail of protease inhibitors was introduced in 1996, it effectively transformed AIDS from a death sentence to a chronic condition—deaths from AIDS in the U.S. went from 50,628 in 1995 to 18,851 in 1998.

That sounds like a miracle drug!

Yes. People throw that term around a lot, but if it applies to any treatment therapy, surely it is antiretrovirals. What’s more, gay men, whose population was disproportionately affected by HIV, essentially saved themselves when the U.S. government and drug companies were too sluggish and apathetic to do so. (Of course, they had plenty of help from other queer people and allies who weren’t themselves infected. See David France’s 2012 documentary How To Survive a Plague.) There are lots of miracles to behold.

And maybe the biggest miracle (or at least the most mind-blowing one) is that people with undetectable levels of HIV in their blood are virtually noncontagious.

There is really a drug that makes HIV—probably the most feared infectious disease as far as our culture is concerned—noncontagious?

That’s right. Transmission of HIV from positive-but-undetectable people looks to be nearly impossible.

I don’t believe you.

That’s fine. I accept you. Wrapping your head around this idea requires an unlearning of so much of the past 30 years. Don’t take my word for it, read the numbers.

The PARTNER study surveyed 767 sero-different couples (in which one member was HIV positive and treated with antiretroviral meds and the other was negative and not on PrEP), gay and straight, who, over two years, practiced condomless sex at least some of the time. Over the course of an estimated 44,400 sex acts, the amount of times the virus was transmitted from the positive partner to the negative was zero.

Zero?

Not once. The implications of this, to quote the report referenced above, are:

When asked what the study tells us about the chance of someone with an undetectable viral load transmitting HIV, presenter Alison Rodger said: “Our best estimate is it’s zero.”

If I believe this, what this suggests is that having sex with an HIV positive person who’s being treated with meds to make his or her viral load undetectable amounts to safe sex (as far as HIV transmission is concerned), even if it’s condomless sex.

There are a lot of buts to consider there, but the Swiss Federal Commission for HIV / AIDS has been saying as much since 2008.

OK, great. I hate condoms, so I’m going to fuck raw with HIV positive people from now on.

Hold on there, cowboy. This isn’t that simple. Antiretrovirals (which are also taken by negative individuals as PrEP) only treat and prevent HIV, not other STIs, including hep-C, which can be deadly, or at least enormously expensive to treat.

There is also the fact that viral loads sometimes fluctuate. The flu can cause them to rise, as can STIs (you know, the kinds of infections you can get from having sex without condoms). A lapse in treatment can also the affect the viral load. Though a person can be relatively certain of his viral load at any given time, this isn’t something that’s checked daily (generally, such testing is administered every three to six months), thus it’s something that one can never be entirely sure of. In preventing HIV, antiretrovirals are great, but the combination of antiretrovirals and condoms is even better.

Also keep in mind that just because the amount of HIV in one’s blood is undetectable, it doesn’t mean that it’s undetectable in other bodily fluids like semen.

But if Charlie Sheen has an undetectable amount of HIV in his blood, how do his former sex partners who are threatening to sue him have a case?

Some states’ HIV disclosure laws do not take into consideration the gains we’ve made through antiretroviral therapy. Legislation is still stuck in the plague years. According to this U.S. News & World Report piece:

State laws vary dramatically in terms of their requirements, explains Sarah Warbelow, legal director at the Human Rights Campaign. They range from having sex with someone to intentionally infect them, to having sex with someone without telling them a diagnosis, even while wearing a condom and using other protection, and even in cases where a partner does not become infected. Some laws include other sexually transmitted infections, or any communicable disease, though laws against HIV are the most aggressive. Heterosexual men of color are most likely to be prosecuted.

...And intercourse isn’t required to sue using HIV disclosure laws: About a quarter of recent prosecutions are for behaviors like spitting or biting, which pose no measurable risk of HIV transmission.

However,

In California, a felony charge is only applied when a partner has demonstrated that someone willfully tried to infect them, Warbelow says. Sheen may face misdemeanor charges that could result in a fine or up to six months in prison. Warbelow says, however, that because he says he is medicated, it would be difficult for plaintiffs to prove that he even willfully exposed them to the virus, given that his doctor says it is undetectable in his blood.

If AIDS deaths dropped to 18,851 in 1998, why have they remained around that level (per the linked report) since then?

There are several reasons for this. Stigma is a tremendous roadblock. A lot of people don’t know they’re infected and thus aren’t being treated. This is particularly so for young gay men of color, who are disproportionately affected by HIV and disproportionately ignored by the various systems providing the resources to treat it. In all likelihood, Charlie Sheen will be fine, but tens of thousands of men won’t be.

Bryan Kutner, my go-to HIV expert and MPH, MS, doctoral candidate, University of Washington, adds, “Tuesday’s interview reminded me of similar interrogations from the ‘80s and ‘90s. Back then, we knew far less and people could feel justified asking questions that slammed a Scarlet Letter onto anyone who either had HIV or might have it.

“There’s so much to hope for now, so much more science that’s helping to motivate people instead of just frighten them. Maybe now people will be more inclined to correct someone who misspeaks about HIV. Maybe it’ll push people to tell their friends about being on PrEP or using treatment as prevention. That’s what I find so positive about including science in this piece — it not only corrects misinformation from Tuesday, it also might be the small nudge for people to correct misinformation when they hear it tomorrow.”

If you’re looking for more info, the HIV/AIDS site The Body has a full range of coverage regarding Sheen’s disclosure.

Special thanks to Kutner, who advised on this entire post, not just the quote above.