Aciclovir, herpes viruses and HIV: a never-ending story

HIV infection continues to be among the leading causes of morbidity and mortality, especially in Africa. The prevalence of herpes simplex virus type 2 (HSV-2) has already reached high seroprevalence of up to 90% in HIV-seropositive individuals, and HSV-2 is now the leading cause of genital ulcer disease in both developing and developed countries. The role of HSV-2 as a biological cofactor in HIV acquisition and transmission may have contributed substantially to HIV diffusion, also facilitating HIV spread among the low-risk population who have stable long-term sexual partnerships. To date, no vaccine to prevent HSV-2 acquisition or reactivation has been developed, although antivirals have been shown to be safe and effective in reducing HSV-2 shedding frequency and the duration of genital ulcer disease. The paper under evaluation confirms the favorable effect of therapies aimed at suppressing HSV-2 reactivation in HIV-seropositive patients on HIV plasma and vaginal load. In this study, aciclovir 400 mg twice daily was able to significantly reduce plasma and genital HIV RNA, the frequency of HIV shedding, genital HSV-2 DNA and the frequency of genital ulcerations. These results suggest that HSV-2 control with low-cost aciclovir can play an important role in reducing HIV spread, mainly in developing countries, where costs limit the use of highly active antiretroviral therapy.