The Potential Role of Undetectable = Untransmittable (U = U) in Reducing HIV Stigma among Sexual Minority Men in the US.

The Undetectable = Untransmittable (U = U) message and its scientific underpinnings have been widely suggested to reduce HIV stigma. However, misunderstanding and skepticism about U = U may prevent this destigmatizing potential from being fully realized. This cross-sectional study examined associations between U = U belief (belief that someone with a sustained undetectable viral load has zero risk of sexually transmitting HIV) and HIV stigma among US sexual minority men. Differences by serostatus and effects of brief informational messaging were also explored. The survey was completed online by 106 men living with HIV and 351 HIV-negative/status-unknown men (2019-2020). Participants were 18-83 years old (M[SD] = 41[13.0]). Most were non-Hispanic White (70.0%) and gay (82.9%). Although nearly all participants (95.6%) were aware of U = U, only 41.1% believed U = U. A greater percentage of participants living with HIV (66.0%) believed U = U compared with HIV-negative/status-unknown participants (33.6%). Among participants living with HIV, U = U belief was not significantly associated with perceived, internalized, or experienced HIV stigma or with viral load prejudice (prejudice against people who have a detectable HIV viral load). Among HIV-negative/status-unknown participants, U = U belief was associated with less frequently enacted HIV discrimination, more positive feelings toward people with an undetectable viral load, and lower personal endorsement of stigmatizing beliefs. Brief informational messaging about U = U did not affect most stigma dimensions and did not favorably affect any. Interventions are needed to correct commonly held, outdated misconceptions about HIV transmission risk. Such initiatives must not only engage people living with HIV but also engage HIV-negative/status-unknown people to maximize the destigmatizing potential of U = U.