The science behind U = U (Undetectable = Untransmittable)

undetectable = untransmittable - positive peers

By: Ann Avery, MD, Infectious Disease Physician at MetroHealth Medical Center

“Undetectable = Untransmittable” isn’t something you keep to yourself. It’s something to shout from the rooftops!

What does it mean? It means that scientists are certain that if your viral load is undetectable and has been for six months or more (200 copies/ml or less), you cannot pass on the virus to anyone else.

They’ve studied thousands of couples who had sex all kinds of ways — with and without condoms. Here’s what they found:

Nada. Nothing. Not one single case of a person living with HIV with an undetectable viral load infecting a sex partner. (Get the hard facts here.)

undetectable = untransmittable - positive peers

Why the “U = U” campaign is so important

Worldwide, health experts and activists believe that the undetectable = untransmittable message will turn public opinion around and make HIV stigma a thing of the past.

Why is spreading the word important?

  1. It shows the power of HIV medication — every dose, every day works!
  2. It proves that your meds not only help you live a happy, healthy life, but they can protect your partner and stop the spread of the virus, too!
  3. Education — about U=U, the incredible medications available, and the new reality of living with HIV in 2018 — will help combat the stigma around the disease.

undetectable = untransmittable - positive peers

Let’s talk science, HIV, and transmission

By now you probably understand how HIV gets into the bloodstream (if you want a refresher course, read our blog). And you may understand that HIV hijacks important cells in your immune system and uses them to multiply.

HIV meds work by interrupting this process, thus keeping the virus from hijacking your immune cells and keeping it from replicating.

The trouble with HIV is that we know how to fight it — but we don’t know how to cure it. Our best HIV meds can’t get rid of every last trace of HIV in the body. So, if you go off your meds, HIV starts reproducing again.

But if you take your meds every day as your doctor says, your viral level becomes incredibly small, like undetectable small. 😉


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Why “undetectable” is so crucial

“Undetectable” is a word describing a measurement — like saying “foot” means 12 inches.

When a person living with HIV has a viral load that falls below 200, it goes into the “undetectable” range.

And when your viral load is undetectable, there simply isn’t enough HIV in your body to infect somebody else when you have sex with them.

If you’re living with HIV but not getting treatment, your viral load could be more than a thousand times higher. And with a thousand times more HIV in your blood, you’re much more likely to infect somebody, not to mention feel like crap!

undetectable = untransmittable - positive peers

Is “U = U” a green light for unprotected sex?

Just because you’re not going to spread HIV to bae doesn’t mean you shouldn’t still consider practicing smarter sex. Reducing your number of partners, talking to your partner(s) about sexual health and getting tested, lube, condoms, and other smarter sex tools can protect you against other sexually transmitted infections.

Now, if your partner isn’t living with HIV, they may still feel a bit nervous despite knowing the science of U=U. Fear is a natural human reaction, even if it’s completely unwarranted. If it will help them feel more empowered, you might suggest they consider taking PrEP (pre-exposure prophylaxis). This once-daily pill will give them some peace of mind and, if for some reason your viral load spikes, it will decrease their chance of contracting the virus by 92-99%.

undetectable = untransmittable - positive peers

Another U we didn’t mention: “unequal”

As long as there’s a stigma about having HIV, people living with the virus will deal with unequal treatment.

Lost friendships, bad relations with parents, outdated laws, and an inability to find decent housing or a good job are forms of discrimination that some folks with HIV face because of stigma.

We believe that everything we do today to spread the word on “U = U” will result in better lives for people who are living with HIV and fewer new cases of the virus.

So go ahead, spread the word. It’s undebatable. Unmistakable. U = U!

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