Several studies have provided consistent data on the effectiveness of viral suppression on HIV transmission, collectively observing more than 100,000 condomless anal and vaginal sex acts that resulted in zero HIV transmissions within serodiscordant couples including a partner living with HIV whose viral load was durably suppressed (<200 copies/mL). With these findings, awareness and dissemination of treatment as prevention, and movements such as “Undetectable = Untransmittable” (U =U), has grown.

Growing Acceptance of U = U

In two published studies, my colleagues and I have shown that beliefs about the accuracy of the U=U message have been growing. In a study of 12,222 gay, bisexual, and other sexual minority men that collected data over 1 month in the summer of 2017—before the CDC and other US public health officials came out in support of U=U—we found that one-third of HIV-negative men believed that U=U was somewhat or completely accurate, compared with more than two-thirds of men living with HIV.

In a follow-up study, published in the Journal of Acquired Immune Deficiency Syndrome and conducted for 10 months in late 2017 and into 2018, after the CDC’s statements, we found these levels had jumped to more than half of HIV-negative men and more than four in five men living with HIV. When looking only among those who completely agreed, corresponding rates were approximately one-fifth for HIV-negative men and more than half of men living with HIV. Moreover, we found evidence that views were shifting over time, toward increased belief in the U=U message. Both studies also identified higher beliefs in U=U among several groups, including HIV-negative men on PrEP, those who recently engaged in condomless anal sex, and those in serodiscordant relationships.

In a forthcoming set of analyses, we examined the meaning of U=U for men living with HIV. Using data from 30,361 sexual minority men living with HIV collected from 2018 to 2019, we found that 59% said U=U made them feel much better about their HIV status, and another 23% said it made them feel a little better. Similarly, 41% and 38% said it had the potential to make HIV stigma much better or a little better, respectively. These hopeful data come with the caveat that men who reported their most recent viral load test was detectable were less likely to report such positive views—though not causal, these data suggest U=U might provide an opportunity to re-engage patients in care who are struggling with retention, adherence, and suppression.

Incorporating the U = U Messaging

Our data have shown that people are learning more and more about U=U and the science of viral suppression and HIV transmission, as well as that beliefs in the message are on the rise. Importantly, the vast majority of men living with HIV believe in the message. Given behavioral factors that are associated with these beliefs, people may be making HIV prevention decisions with U=U in mind. Most importantly, our data suggest that U=U holds substantial promise for improving the lives of people living with HIV, providing a greater sense of self-esteem and hope for the positive impact it might have on HIV stigma. As such, I strongly urge healthcare professionals (HCPs) to consider routine discussions of viral suppression, HIV transmission, and U=U with their patients.

Discussing U=U and the science behind viral suppression and transmission with patients is now a common recommendation by HIV-related medical and public health organizations. Our data show the majority of our participants had heard of U=U and most were learning about it from apps, websites, sex partners, and friends—not their HCPs. Although some HCPs may have concerns about U=U, open and honest conversations would provide an opportunity to weigh pros and cons with patients and provide an opportunity to correct any misinformation or provide a more nuanced opinion of its applicability to each patient’s unique circumstances.

Several resources exist to learn more about U=U and how to integrate it into practice. The International Association of Providers in AIDS Care has launched an e-course about how to message U=U to patients. The Prevention Access Campaign’s website also contains information and resources that can help.