Opposites attract study

The Opposites Attract study looked at male HIV serodiscordant couples in Australia, Brazil and Thailand, from May 2014 (Australia) or May 2016 (Brazil/Thailand) to December 2016.

The study recruited 358 serodiscordant couples. Many men in the couples enrolled in our study relied on undetectable viral load to reduce transmission of HIV, along with other strategies such as condom use, PrEP, strategic positioning and withdrawal. Only a very small proportion of anal intercourse acts within the serodiscordant couples in the study were not protected by any strategy. Variation between countries may reflect differences in access to HIV treatment, education, knowledge and attitudes.

Despite the perception of male serodiscordant couples as very high risk, these data suggest that for the most part, HIV transmission risk in these couples was low. Studies have now confirmed that transmission risk is low when HIV-positive partners have undetectable viral load.