Can U=U be used to reshape HIV programmes globally?

Image: Campaign materials on the Vietnamese U=U (K=K) website

Research presented to the 23rd International AIDS Conference (AIDS 2020: Virtual) last week on 'Undetectable = Untransmittable' (U=U) indicates varying levels of awareness and acceptance of this powerful message, despite the conclusive finding that people living with HIV who have an undetectable viral cannot infect others.

Launched in mid-2016 by activists and researchers in New York City, the community-led U=U movement has engaged more than 1000 organisations from 100 countries and key populations on every continent. In a plenary presentation, Dayana Hernandez from Transvida, an organisation offering services to transgender women in Costa Rica, emphasised the central role of civil society organisations who work with people living with HIV in spreading the U=U message. However, she also said that governments need to endorse U=U for it to have maximum impact on stigma reduction and as a way of preventing HIV infections.

This has happened in Vietnam. Asia Nguyen, from the US Centers for Disease Prevention and Control in Vietnam, shared how both the Ministry of Health and community leaders there have embraced U=U as a central component of overall HIV prevention efforts, in addition to using it to reduce stigma. This has included challenging misperceptions of HIV and communicating the importance of U=U to people living with HIV, younger men who have sex with men (MSM), reluctant health professionals, and the broader public through tailored advertising campaigns, starting at a community level and progressing to a national campaign.


Undetectable = Untransmittable (U=U)

U=U stands for Undetectable = Untransmittable. It means that when a person living with HIV is on regular treatment that lowers the amount of virus in their body to undetectable levels, there is zero risk of passing on HIV to their partners. The low level of virus is described as an undetectable viral load. 


Social attitudes that suggest that having a particular illness or being in a particular situation is something to be ashamed of. Stigma can be questioned and challenged.

key populations

Groups of people who are disproportionately affected by HIV or who are particularly vulnerable to HIV infection. Depending on the context, may include men who have sex with men, transgender people, sex workers, people who inject drugs, adolescent girls, prisoners and migrants.

virological suppression

Halting of the function or replication of a virus. In HIV, optimal viral suppression is measured as the reduction of viral load (HIV RNA) to undetectable levels and is the goal of antiretroviral therapy.


Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

Vietnam is the first PEPFAR country to achieve viral suppression in over 95% of people on antiretroviral treatment and officially endorse U=U via national guidelines.


Thiago Torres, from the Oswaldo Cruz Foundation (FIOCRUZ), a health research institution in Brazil, presented data showing that beyond groups directly affected by HIV, widespread awareness and acceptance of U=U remains limited in the country.

Adults were recruited via Grindr, Facebook and WhatApp and completed a survey including the question: “With regards to HIV-infected individuals transmitting HIV through sexual contact, how accurate do you believe the slogan U=U (undetectable equals untransmissible) is?” This was the same question used in prior research in the US.

The final sample included responses from 1690 individuals: including 20% from people living with HIV, 46% from MSM with a negative or unknown status while other populations (such as heterosexual men and women) with an HIV-negative or unknown status made up the rest of the sample. MSM were younger (a median age of 33) compared to people living with HIV (a median age of 40) and other populations (a median age of 48). The sample was predominantly white, well-educated and relatively affluent.

While the vast majority of people living with HIV perceived U=U as accurate (90%), only 68% of the HIV-negative MSM viewed it as such. This decreased to 35% of participants belonging to other populations stating that U=U is accurate. Across all groups, those under the age of 35 were more likely to perceive U=U as accurate.

People living with HIV who identified as black were less likely to accept that U=U, while those living with HIV with a steady partner were more likely to do so. MSM from low-income groups were less likely to perceive U=U as accurate.


U=U (or K=K, as it is known in Vietnamese) has been positioned as the central component of Vietnam’s response to their HIV epidemic. This is based on clear scientific evidence that successful ART leads to sustained viral suppression, providing complete protection against the sexual transmission of HIV.

This crucial message has also been used to influence HIV programme planning in Vietnam. Health officials view U=U as a versatile message that is relevant to stigma reduction, engagement with HIV treatment, testing and PrEP.

In terms of starting treatment and maintaining good adherence, the idea of U=U provides a framework to understand the purpose of taking treatment and can also be used a way of measuring treatment success. Understanding of the term ‘viral load’ is central to the U=U message. Education on the importance of viral load monitoring helps to increase the knowledge of both healthcare providers and people living with HIV, while providing a motivation and creating a demand for routine viral load testing.

Nguyen highlighted important factors that contributed to success in Vietnam:

  • Government endorsement of the U=U message: the Ministry of Health was quick to accept evidence supporting U=U in 2017 and the country was one of the first to consider an undetectable viral load (< 200 copies/ml) as an indicator of treatment success. This information was shared on platforms widely accessible to the public, such as talk shows.
  • Community leadership: it was important for government and community agencies to co-ordinate activities, in order to spread the U=U message to those who most needed to hear it, especially key populations such as people living with HIV, people who inject drugs and young MSM. Community organisations have received grants and community leaders have used diverse platforms to engage members, including community discussions, peer outreach and high-profile social events.
  • City campaigns: U=U campaigns were first developed in the country’s two largest cities, to change public perceptions of HIV and to encourage the acceptance of the idea that an undetectable viral load provides complete protection against HIV infection. The provocative campaigns focused on key populations. Success in these cities encouraged broader commitment to the U=U message.
  • Getting healthcare providers onboard: many healthcare providers were reluctant to share the U=U message with their clients. This required messaging aimed at providers, directly addressing their concerns and educating them on U=U. This information was provided in the form of posters and web pages that could be used in clinical settings. The simple, clear visuals and text illustrated the basics of U=U in a way that ensured providers would feel confident sharing this information with their clients.
  • Finding programme ‘champions’: this included highlighting healthcare providers who supported the U=U message and their successes. Healthcare ‘champions’ have helped put U=U into practice in clinical settings by providing training and technical assistance at health facilities.
  • Creating a national campaign: this celebrated U=U as transformative for individuals, couples and communities. This campaign contrasted with the outdated framing of HIV as a death sentence and instead focused on health and longevity resulting from viral suppression. This campaign has been seen everywhere from Facebook to bus stops.
  • Evolution to an antiretroviral prevention framework and status-neutral services: Vietnam’s next step will be moving towards providing status-neutral services by giving individuals, couples and communities the preventative medication required, either in the form of treatment as prevention for those living with HIV or pre-exposure prophylaxis (PrEP) for those who are HIV-negative.


These presentations indicate that multiple steps are necessary for U=U to be implemented as a core component of a country’s overall HIV prevention programming. Widespread awareness and acceptance of U=U are crucial. The study from Brazil represents an important first step in identifying where education is required and how it can be tailored to the needs of specific groups while Vietnam provides an encouraging example of U=U’s potential to reshape national HIV service provision.


Hernandez, D. U=U: global perspectives. Plenary session, 23rd International AIDS Conference, 2020.

Nguyen, A. et al. Undetectable = Untransmittable (U=U) to drive stigma reduction and epidemic control in Vietnam: A global model for political and program innovation. 23rd International AIDS Conference, oral abstract OAF03, 2020.

Torres, T. S. et al. A call to improve understanding of Undetectable equals Untransmissible (U=U) slogan in Brazil. 23rd International AIDS Conference, oral poster discussion, PDD05, 2020.