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Can't Pass It On

People on effective HIV treatment cannot pass on the virus. Fact.

We’ve got an important message to share this summer.

Medical evidence has shown that people on effective HIV treatment can’t pass it on.

If everyone knew this, we could bring an end to stigma around HIV. Not only that, but we could stop HIV transmissions all together.

We’ve launched our Can’t Pass It On campaign, to spread this message far and wide.

The science bit

For the past 20 years, evidence has been building to show that your likelihood of passing on HIV is linked to the amount of the virus in your blood.

Last year, the landmark PARTNER study looked at over 58,000 instances of sex without a condom, where one partner was HIV positive and one was HIV negative. Results found that where the HIV positive partner was on effective treatment (reducing the amount of the virus to ‘undetectable’ levels), there were zero cases of HIV transmission.

This gives us the robust evidence to say, with confidence, that people on effective HIV treatment can’t pass on the virus.

Dr Christian Jessen headshotThe campaign is supported by Dr Christian Jessen, who said:

'Scientific evidence shows that people on effective treatment for HIV are not infectious.

'This is because the treatment will reduce the amount of the virus in their blood to such a low level that it is no longer able to infect someone via the usual routes.

'That’s a really important and remarkable thing for a number of reasons. First of all, it means there should be no new HIV infections. We can stop HIV being passed on by encouraging people to get tested and treated.

'Secondly, it should take away all the stigma, and it really does allow people to have relationships and live normal lives without fear.

'But the reality is so far from what most people’s awareness of HIV is, and there’s still so much work to do before people are up to date with what HIV means today.'

Want to learn more? Dr Michael Brady, our medical director, has answered your questions about what it means to be ‘undetectable’.


Currently, only 9% of the public know that people on effective treatment can’t pass on HIV.

Pass the message on today. Every share will help educate and change lives.

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Join us

Many people living with HIV face unfair judgement and discrimination. Not only does this stigma hurt people living with HIV, it also prevents more people coming forward for testing. Please join us to stop this.

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The Information Standard: Certified member

This article was last reviewed on 26/6/2017 by

Date due for the next review: 26/6/2020

Content Author: Dr Michael Brady

Current Owner: Emily Rosselli

More information:


  • Gray et al Probability of HIV-1 transmission per coital act in monogamous, heterosexual, HIV-1-discordant couples in Rakai, Uganda. The Lancet Volume 357, No. 9263, p1149–1153, 14 April 2001
  • In January 2008 the Swiss National AIDS Commission issued what was subsequently to be known as 'The Swiss Statement' stating that: ‘An HIV-infected person on antiretroviral therapy with completely suppressed viraemia (“effective ART”) for over six months and with no STIs is not sexually infectious, ie, cannot transmit HIV through sexual contact.’
  • Cohen et al Antiretroviral Therapy for the Prevention of HIV-1 Transmission N Engl J Med 2016; 375:830-839
  • Rodger et al for the PARTNER study group. Sexual activity without condoms and risk of HIV transmission in serodifferent couples when the HIV-positive partner is using suppressive antiretroviral therapy. JAMA, 2016;316(2):1-11
  • Partners PrEP Study:
    National Center for Biotechnology Information
    US National Library of Medicine
    HIV Transmission Risk Persists During the First 6 Months of Antiretroviral Therapy.
    Mujugira A, Celum C, Coombs RW, Campbell JD, Ndase P, Ronald A, Were E, Bukusi EA, Mugo N, Kiarie J, Baeten JM; Partners PrEP Study Team
    Aug 15 2016;72(5):579-84. doi: 10.1097/QAI.0000000000001019
  • HPTN 052 Study:
    National Center for Biotechnology Information
    US National Library of Medicine
    HIV treatment as prevention and HPTN 052
    Cohen MS, McCauley M, Gamble TR
Can't pass it on

People on effective treatment can't pass on HIV

If everyone knew this, we could bring an end to stigma and stop HIV transmissions.

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