Belief, Covariates, and Impact of the "Undetectable = Untransmittable" Message Among People Living with HIV in Australia

There is effectively no risk of transmission of HIV from an HIV-positive person with consistent undetectable viral load (UDVL) to an HIV-negative person during sex. This has been publicly disseminated by an international health campaign called "undetectable = untransmittable" (U = U). This study extends previous research by examining confidence in the U = U message and potential covariates of confidence in U = U, as well as by assessing the perceived personal risk and sexual outcomes in a sample of people living with HIV (PLWH) in Australia. Between October 2017 and June 2018, 139 adult PLWH were recruited through clinics or community-based strategies. They completed an online questionnaire assessing participant characteristics, general agreement with the U = U message, confidence in U = U as an effective HIV prevention strategy, perceived personal risk of onward transmission, and sexual outcomes. While the majority of participants (70.5%) agreed with the general U = U message, only 48.2% were confident in U = U as an effective HIV transmission prevention strategy across sexual situations. Lack of confidence in U = U was more pronounced in the community subsample, minority group participants, and lower educated participants. A minority of PLWH with self-reported UDVL thought they could pass on HIV and indicated poor sexual outcomes, including sexual inactivity, reduced frequency of sex, and reduced sexual satisfaction. General agreement with the U = U message among PLWH may mask lack of confidence in U = U. Community-based information and education tailored to culturally diverse groups and people with low health literacy are required to promote accurate perception of risk of transmission of HIV with consistent UDVL.