When the human immunodeficiency virus (HIV) is successfully suppressed by medication, people with HIV can't transmit the virus to others, according to a public policy statement from a coalition of community health and HIV/Aids organisations.
Modern drugs for HIV, the virus that causes Aids, can often achieve viral suppression, meaning levels of the virus have been reduced to undetectable levels in the blood. And now, Reuters Health report, the AIDS United Public Policy Committee has issued a statement that said virally suppressed people on treatment can't pass HIV to others, and it recommended that healthcare providers and educators share this message with the public.
"We feel that the science is very strong on this and felt comfortable making that statement," said Ronald Johnson, AIDS United's vice president of policy and advocacy in Washington, DC.
The report says an expert not involved in the coalition said she didn't completely agree – but she did say the risk of transmission in such cases would be "negligible."
People who start treatment for HIV with so-called antiretroviral therapy (ART) can be virally suppressed within 12 to 24 weeks, according to the US Department of Health and Human Services (HHS). Viral suppression can be lifelong if people stay on their medicine.
Over 1.2m people in the US are currently living with HIV, according to the Centres for Disease Control and Prevention. Of those, 86% are aware of their diagnosis, 37% are on treatment to stop the virus from replicating and 30% are virally suppressed.
A study published last year examined the risk of transmission between a person living with well-controlled HIV and their HIV-negative partner. Among 548 opposite-sex and 340 same-sex couples having unprotected sex, only 11 of the HIV-negative partners became positive over about a year and a half of follow up. None of the new infections could be traced back to the partners with HIV.
Those researchers and others, however, did not go so far as to say the risk of transmission is zero. They emphasised that more data is needed – particularly for condomless anal sex. "We felt looking at these studies, there is substantial evidence that we can come to the conclusion that people living with HIV that have sustained and undetectable viral load cannot transmit HIV," Johnson is quoted as saying.
Dr Michelle Cespedes, associate professor of infectious disease at Icahn School of Medicine at Mount Sinai in New York, said it's impossible to say transmission would never occur with condomless sex.
Importance: A key factor in assessing the effectiveness and cost-effectiveness of antiretroviral therapy (ART) as a prevention strategy is the absolute risk of HIV transmission through condomless sex with suppressed HIV-1 RNA viral load for both anal and vaginal sex.
Objective: To evaluate the rate of within-couple HIV transmission (heterosexual and men who have sex with men [MSM]) during periods of sex without condoms and when the HIV-positive partner had HIV-1 RNA load less than 200 copies/mL.
Design, Setting, and Participants The prospective, observational PARTNER (Partners of People on ART—A New Evaluation of the Risks) study was conducted at 75 clinical sites in 14 European countries and enrolled 1166 HIV serodifferent couples (HIV-positive partner taking suppressive ART) who reported condomless sex (September 2010 to May 2014). Eligibility criteria for inclusion of couple-years of follow-up were condomless sex and HIV-1 RNA load less than 200 copies/mL. Anonymized phylogenetic analysis compared couples’ HIV-1 polymerase and envelope sequences if an HIV-negative
if an HIV-negative partner became infected to determine phylogenetically linked transmissions.
Exposures: Condomless sexual activity with an HIV-positive partner taking virally suppressive ART.
Main Outcomes and Measures: Risk of within-couple HIV transmission to the HIV-negative partner
Results: Among 1166 enrolled couples, 888 (mean age, 42 years [IQR, 35-48]; 548 heterosexual [61.7%] and 340 MSM [38.3%]) provided 1238 eligible couple-years of follow-up (median follow-up, 1.3 years [IQR, 0.8-2.0]). At baseline, couples reported condomless sex for a median of 2 years (IQR, 0.5-6.3). Condomless sex with other partners was reported by 108 HIV-negative MSM (33%) and 21 heterosexuals (4%). During follow-up, couples reported condomless sex a median of 37 times per year (IQR, 15-71), with MSM couples reporting approximately 22 000 condomless sex acts and heterosexuals approximately 36 000. Although 11 HIV-negative partners became
HIV-positive (10 MSM; 1 heterosexual; 8 reported condomless sex with other partners), no phylogenetically linked transmissions occurred over eligible couple-years of follow-up, giving a rate of within-couple HIV transmission of zero, with an upper 95% confidence limit of 0.30/100 couple-years of follow-up. The upper 95% confidence limit for condomless anal sex was 0.71 per 100 couple-years of follow-up.
Conclusions and Relevance: Among serodifferent heterosexual and MSM couples in which the HIV-positive partner was using suppressive ART and who reported condomless sex, during median follow-up of 1.3 years per couple, there were no documented cases of within-couple HIV transmission (upper 95% confidence limit, 0.30/100 couple
years of follow-up). Additional longer-term follow-up is necessary to provide more precise estimates of risk.
Valentina Cambiano, Tina Bruun, Pietro Vernazza, Simon Collins, Jan van Lunzen, Giulio Maria Corbelli, Vincente Estrada, Anna Maria Geretti, Apostolos Beloukas, David Asboe, Pompeyo Viciana, Félix Gutiérrez, Bonaventura Clotet, Christian Pradier, Jan Gerstoft, Rainer Weber, Katarina Westling, Gilles Wandeler, Jan M Prins, Armin Rieger, Marcel Stoeckle, Tim Kümmerle, Teresa Bini, Adriana Ammassari, Richard Gilson, Ivanka Krznaric, Antonio Antela, Sris Allan, Andrew N Phillips, Jens Lundgren