Viral suppression may translate to safe sex among couple with an HIV positive individual.
A study published in JAMA found that among couples of serodifferent heterosexual and men who have sex with men (MSM), the HIV-positive partner who used suppressive antiretroviral therapy (ART) and engaged in condomless sex had no documented cases of within-couple HIV transmission.
The study was conducted at 75 clinical sites in 14 European countries to evaluate the rate of within-couple HIV transmission (heterosexual and MSM) during periods of sex without condoms, and when the HIV-positive partner had HIV-1 RNA load less than 200 copies/ml.
There were 1166 HIV serodifferent couples enrolled in the study, with the HIV-positive partner taking suppressive ART. Among the enrolled couples, 888 (62% heterosexual; 38% MSM) provided 1238 eligible couple-years of follow-up (median follow-up 1.3 years).
Couples reported condomless sex for a median of 2 years at study entry. Condomless sex with other partners was reported by 108 HIV-negative MSM (33%) and 21 heterosexuals (4%).
During the follow-up, couples reported a median of 37 times per year for condomless sex, while MSM couples had approximately 22,000 condomless sex acts and 36,000 for heterosexuals. The results of the study found that 11 HIV-negative partners did become HIV-positive (10 MSM; 1 heterosexual; 8 condomless sex with other partners), but there were no phylogenetically linked transmissions that occurred over the couple-years of follow-up, resulting in a rate of 0 for within-couple HIV transmission.
“Although these results cannot directly provide an answer to the question of whether it is safe for serodifferent couples to practice condomless sex, this study provides informative data (especially for heterosexuals) for couples to base their personal acceptability of risk on,” the study authors wrote.
The researchers noted that the confidence limits used in the study suggest that with eligible couple-years accrued so far, appreciable levels of risk can’t be excluded, particularly for anal sex, and when considered from the perspective of a cumulative risk of many years. Furthermore, additional longer-term follow-up is required to provide a similar level of confidence for the risk from anal sex compared with vaginal sex.
“For individuals who want to routinely or intermittently not use condoms with an HIV-infected partner, clinicians can indicate that the risk of HIV transmission appears small in the setting of continued viral suppression, emphasizing that the duration the HIV-infected partner needs to be virologically suppressed before achieving optimal protection is unknown, although appears to be for at least 6 months, based on the best available data,” wrote Eric S. Daar, MD, and Katya Corado, MD, in an accompanying editorial.
“Moreover, clinicians need to be clear that even though the overall risk for HIV transmission may be small, the risk is not zero and the actual number is not known, especially for higher-risk groups such as MSM,” Daar and Corado continued. “Although more research is needed with larger numbers of couples and longer follow-up, it is not known if or when such data will emerge. Consequently, for now, clinicians and public health officials must share the data that exist in an honest and understandable way so that serodiscordant couples can be fully informed when individualizing their decision making about sexual practices.”