What is U=U?

U=U means Undetectable equals Untransmittable. This is a campaign that is being adopted all over the world to help create awareness about new ways to prevent HIV transmission. A person with a sustained undetectable viral load cannot pass on HIV. You can learn more about the campaign through Pride for Youth or at https://www.preventionaccess.org/.


What does ‘undetectable viral load’ mean?  

Viral load refers to the amount of HIV in a blood sample of a person living with HIV. Generally, the higher the viral load, the more likely a person is to transmit HIV. Conversely, the lower a viral load, the less likely a person is to transmit HIV.   Both “undetectable” and “viral load suppression” are extremely low measurements of HIV that are virtually the same. The terms are often used interchangeably in public health communications. This means someone who is living with HIV but is undetectable or virally suppressed cannot pass on the virus through sex.


What is the science behind this?

There have been multiple studies looking into HIV transmission and an undetectable status. The conclusion of U=U is based on the force of real world and research experience including PARTNER, HPTN 052, Opposites Attract, and the Swiss Statement. In the PARTNER study, there were ZERO transmissions out of 58,000 condomless sex acts between people with HIV with undetectable viral loads and their partners who are HIV negative. In the the most recent study called Opposites Attract, there were no transmissions out of 17,000 condomless sex acts between men.  Since the advent of combination therapy, there have been no confirmed reports of anyone with an undetectable viral load sexually transmitting HIV. To look further into these studies you can click the links at the bottom of this page.


Is the risk zero?

In basic terms, yes, the risk is zero. Theoretically, and based off the science, the amount of risk for transmission is a small fraction close to zero. The challenge of this is that scientific studies can never prove zero risk. However, researchers agree that because the actual HIV transmission risk is either zero or extremely close to zero, a person with HIV with an undetectable viral load is considered “not infectious” to their sexual partners.


What does “Treatment as Prevention” mean?

This statement means that, because of this new U=U message, being on treatment and getting to an undetectable viral load can prevent further spread of HIV. By doing this, essentially, a person who is living with HIV is using their treatment plan as another prevention tool just like PrEP and condoms.


How can I become Undetectable?

Most commonly, if a person living with HIV sees their doctor regularly and is adherent to their medication for a sustained period of time (approximately six months) a person can become undetectable. To maintain this status a person needs to continue this regiment. However, everyone is different and we recommend discussing this issue with a medical professional to find out what will be best for you.


Does U=U apply to transmission through needle sharing? 

U=U does not apply to HIV transmission through needle sharing. There is not yet enough research to draw a conclusion.


Why should this matter to me?

If you are living with HIV this is a very important message about getting healthy and staying healthy. By embracing and understanding U=U it may help with fear or anxiety felt about potentially transmitting the virus.

If you are HIV-negative this message allows you to have more options when looking at your HIV prevention toolkit and can help facilitate healthy conversations about sex between you and your partner.



Information for this FAQ was used in partnership with Prevention Access Campaign. For a more detailed FAQ please follow the link to https://www.preventionaccess.org/faq or http://longislandcrisiscenter.org/prideforyouth.

For more information contact our Community Mobilization Coordinator Scott Petersen at (516) 679-9000 ex. 17 or spetersen@longislandcrisiscenter.org