Objective: The potential role of antiretroviral treatment on the infectiousness of HIV-1-infected men was examined by studying the effect of antiviral treatment on the shedding of HIV-1 in semen.
Methods: Forty-four patients enrolled in various treatment protocols were asked to donate a semen sample before they began a new antiviral treatment and at a follow-up visit after 6 to 15 weeks of treatment. Since most patients were on blinded protocols, patients were stratified by response of blood viral load. The effect of each patient's treatment was classified as good (n = 24), fair (n = 8) and marginal (n = 13) by measurement of the HIV RNA reduction in blood plasma (> 1.0 log10; 0.5-1.0 log10 and < 0.5 log10 HIV RNA copies/ml reduction, respectively). The effect of treatment on shedding of HIV-1 in semen was documented by the reduction of HIV RNA concentration in seminal plasma and by quantitative HIV-1 seminal cell culture.
Results: Overall, antiviral treatment resulted in a significant fall in the viral load in semen (RNA and culture) that paralleled the reduction of viral load in blood. More pronounced reductions of HIV RNA in semen were observed as the effectiveness of treatment on blood HIV RNA levels increased (median drop from baseline 0, 0.3 log10 and 0.8 log10 RNA copies/ml in patients with marginal, fair and good treatment effect, respectively). Thirteen patients lost detectable HIV RNA in blood on treatment and all of these had undetectable levels of HIV-1 in semen by culture and RNA analysis at follow-up. In 19 of the 31 patients (62%) who still had HIV RNA in their blood during treatment, semen HIV levels were below detection in semen at follow-up.
Conclusions: Treatment-induced changes of HIV RNA concentration in blood are generally associated with a corresponding change in seminal HIV RNA: If confirmed in larger studies, potent antiretroviral therapy might reduce the spread of HIV-1.