Background: The level of evidence for HIV transmission risk through condomless sex in serodifferent gay couples with the HIV-positive partner taking virally suppressive antiretroviral therapy ART is limited compared with the evidence available for transmission risk in heterosexual couples. If a seroconversion occurred in the HIV-negative partner, anonymised phylogenetic analysis was done to compare HIV-1 pol and env sequences in both partners to identify linked transmissions.
Incidence rate of HIV transmission was calculated as the number of phylogenetically linked HIV infections that occurred during eligible couple-years of follow-up divided by eligible couple-years of follow-up. During eligible couple-years of follow-up, couples reported condomless anal sex a total of 76 times.
Interpretation: Our results provide a similar level of evidence on viral suppression and HIV transmission risk for gay men to that previously generated for heterosexual couples and suggest that the risk of HIV transmission in gay couples through condomless sex when HIV viral load is suppressed is effectively zero.
Funding: National Institute for Health Research. Published by Elsevier Ltd. Published by Elsevier Ltd.. All rights reserved. Abstract Background: The level of evidence for HIV transmission risk through condomless sex in serodifferent gay couples with the HIV-positive partner taking virally suppressive antiretroviral therapy ART is limited compared with the evidence available for transmission risk in heterosexual couples.
