What is "undetectable"?


Getting to “undetectable” is often the primary goal of treatment for people living with HIV.

What does it mean?

People say HIV viral load is “undetectable” when the levels of virus in the blood stream are so low that they can't be measured. When a person takes their HIV medications every day as they're prescribed, the HIV medications are able to prevent the virus from replicating (or making copies of itself). When this happens, the amount of HIV in a person's blood stream goes down to a level so low that viral load tests aren't able to detect HIV in the person's blood: so we say the person's viral load is undetectable.

Why is it important?

Getting to undetectable is important for a few reasons.

First, people who reach—and maintain—an undetectable viral load are healthier. Getting on HIV treatment right away and getting to undetectable helps make sure that you don't develop AIDS-related conditions like Kaposi's sarcoma and other serious health events like heart disease.

Getting your viral load down to undetectable also helps prevent new infections. Studies show that people living with HIV who are on treatment and have a suppressed viral load do not transmit HIV to HIV-negative sex partners. In other words, if you are living with HIV and have an undetectable viral load, you don’t have to worry about passing HIV on to your sex partners. For many people, being undetectable offers a renewed sense of freedom, brings less anxiety around sex, and reduces stigma associated with HIV.

Does it mean I'm cured?

No. HIV-negative and undetectable are not the same thing. If you stop taking your HIV-medications (and sometimes for other reasons as well) your viral load will go back up to detectable levels. That's why it's important to continue to take your HIV medications every day in the way your provider has instructed.

How long will it take for me to get to undetectable?

It's different for every person. It depends on how high your viral load was before you started treatment, your CD4 cell count, your general health and also what medications you're taking. Generally, the goal is to get to undetectable after 16 – 24 weeks of treatment.

Have more questions? Read about the research on treatment as prevention—and why we know it work to prevent HIV infections. Also, find out more about why people might not get to undetectable in a Q&A with Dr. Keith Henry.         

San Francisco AIDS Foundation supports the Undetectable = Untransmittable message by Prevention Access Campaign. Read more about the initiative.

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