Preventing HIV transmission: Undetectable = Untransmittable (U=U): Communication tips for health professionals

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Organization: Public Health Agency of Canada

Date published: 2023-12-05

ISBN: 978-0-660-68950-0

What is U=U?

U=U stands for Undetectable = Untransmittable. U=U is a health promotion campaign used to promote the scientific consensus that HIV cannot be sexually transmitted when a person living with HIV is on treatment and maintains a viral load (i.e., the amount of virus in the blood) of less than 200 copies/ml (measured every 4-6 months)Footnote 1Footnote 2Footnote 3Footnote 4Footnote 5Footnote 6.

Health professionals can increase the uptake of treatment, prevent new infections, and reduce HIV-related stigma by fully understanding and communicating the undeniable benefits of HIV treatment to people living with HIV and their sexual partners.

  • Viral Load = Less than 200 copies/ml

What to tell your patients

  • HIV treatment can help ensure you live a long, healthy life.
  • When you take HIV medication consistently, the amount of HIV in your blood lowers, which helps keep the immune system strong and prevents illness. When the amount of HIV in your blood gets very low, which is defined as less than 200 copies/ml, you have achieved what is called viral suppression, or what is often called "undetectable".
  • When you achieve and maintain a very low level of virus in your blood (viral suppression), you cannot pass HIV to others through sex.
  • To keep the amount of virus in your blood very low, it is important to take your medication as prescribed.
  • An undetectable viral load means that the level of HIV in a person's blood is so low that it does not show up in standard tests. Due to ongoing advances in testing, the exact number for "undetectable" may continue to change, but it is important to remember that any test result that shows a number less than 200 copies/ml means that HIV cannot be passed on.

Tips for talking about U=U with patients

1. Communicate U=U to everyone

U=U is a message that is applicable to everyone, whether they live with HIV or not, when it is framed as a part of self-care and overall wellness. By openly discussing the U=U message as part of general sexual health messaging, health professionals can dismantle HIV-related stigma and discrimination, and help normalize and promote sexual health. The further the U=U message is shared, the more positive impact it can have.

2. Be clear and consistent

Use clear, direct, and easy to understand language and avoid phrases that make risk levels difficult to interpret or convey doubt. Acceptance of U=U can take time and repetition, as it is challenging to unlearn decades of fear and misinformation around HIV. Even when language about risk is accurate, cautionary phrases and attitudes can undermine the U=U message.

Do say: Don't say:
  • Can't pass it on
  • No risk of transmission
  • U=U is based on scientific fact
  • Nearly impossible to transmit
  • Essentially no risk
  • I believe U=U, but use a condom just in case

3. Be empathetic and don't use stigmatizing language

Being diagnosed with HIV can be life changing, so it is important that health professionals empathize with their patients and communicate without using stigmatizing language. Building trust with patients is foundational for a positive relationship with the healthcare system, and using empathetic language can foster this trust. For example, instead of saying "U=U means sexual partners cannot catch HIV," say "cannot pass HIV" or "cannot acquire HIV". A person is more than just their medical condition; therefore, it is important to ensure that people living with HIV do not feel like a vector of disease, as that can negatively affect their self-esteem and confidence.

Compassionate communication can support the wellbeing of people living with HIV by establishing a patient-provider relationship built on trust. As a result, patients are empowered to make informed decisions about their health, thus increasing the likelihood of adherence to treatment.

4. Be positive

With a positive approach, patients can feel empowered to have control of their wellbeing and make informed choices about their sexual health. Health professionals should highlight the benefits of medication and emphasize that people living with HIV can lead long, healthy lives.

5. Focus on the basics

U=U does not need to be complicated. To ensure patients understand U=U and what they need to do to achieve viral suppression, keep it simple and encourage patients to do the following:

  • Stay on prescribed treatment and attend regularly scheduled medical appointments.
  • Monitor viral load through regular testing every 4 to 6 months.
  • Communicate any experiences that may disrupt adherence to medication, such as barriers to access medication or negative side effects.

6. Be mindful of diverse life experiences

Some populations experience systemic and structural challenges to achieving and maintaining viral suppression due to inequitable access to medication or quality care. For example, some patients may prioritize buying food or paying rent instead of buying medication. Health professionals should be mindful of the diverse lived realities of their patients and ask them about their current circumstances and their own health priorities.

When needed, health professionals should help connect patients to social or other services that will support them in overcoming barriers and promote other highly effective ways to prevent HIV from being passed during sex. This includes using condoms, and using medicines like pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) for the sexual partner who does not HIV. Everyone living with HIV has the right to full and healthy social and sexual lives.

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Footnote 1

Cohen MS, Chen YQ, McCauley M, Gamble T, Hosseinipour MC, Kumarasamy N, et al. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med. 2011;365(6):493-505.

Return to footnote 1 referrer

Footnote 2

Cohen MS, Chen YQ, McCauley M, Gamble T, Hosseinipour MC, Kumarasamy N, et al. Antiretroviral therapy for the prevention of HIV-1 transmission. N Engl J Med. 2016;375(9):830-839.

Return to footnote 2 referrer

Footnote 3

Rodger AJ, Cambiano V, Bruun T, Vernazza P, Collins S, van Lunzen J, et al. 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):171-181.

Return to footnote 3 referrer

Footnote 4

Rodger AJ, Cambiano V, Bruun T, Vernazza P, Collins S, Degen O, et al. Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): final results of a multicentre, prospective, observational study. Lancet. 2019;393(10189):2428-2438.

Return to footnote 4 referrer

Footnote 5

Bavinton BR, Pinto AN, Phanuphak N, Grinsztejn B, Prestage GP, Zablotska-Manos IB, et al. Viral suppression and HIV transmission in serodiscordant male couples: an international, prospective, observational, cohort study. Lancet HIV. 2018;5(8):e438-e447.

Return to footnote 5 referrer

Footnote 6

LeMessurier, J., Traversy, G., Varsaneux, O., Weekes, M., Avey, M. T., Niragira, O.,... & Rodin, R. (2018). Risk of sexual transmission of human immunodeficiency virus with antiretroviral therapy, suppressed viral load and condom use: a systematic review. Cmaj, 190(46), E1350-E1360.

Return to footnote 6 referrer

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