Messaging About HIV Transmission Risk When Viral Load Is Undetectable: Reactions and Perceived Accuracy Among US Sexual Minority Men.

Background: Scientific evidence indicates that HIV viral suppression to an undetectable level eliminates sexual transmission risk ("Undetectable=Untransmittable" or "U=U"). However, U=U messaging has been met with skepticism among sexual minority men (SMM) and others. In this survey-based experiment, we manipulated messaging about HIV risk and examined reactions and perceived message accuracy among US SMM.