Health 23 February 2016 Drug-infused vaginal ring shows promising signs in battle against HIV rates Silicone ring containing antiretroviral dapivirine drug could play an important role in preventing HIV infections. STEPHANE DE SAKUTIN/AFP/Getty Sign UpGet the New Statesman's Morning Call email. Sign-up A medicated anti-viral vaginal ring has been found to reduce the rate of HIV infection in women through trials conducted in Africa, where HIV is prevalent. Two separate studies used this experimental form of prevention, which sees women insert the ring containing dapivirine, an antiretroviral drug that hinders HIV, which is slowly released over time. Each silicone ring lasts 30 days and can be replaced with a new one. The first study, funded by NGO International Partnership for Microbicides, found that the risk of HIV infection dropped by 31 per cent among the 1,959 South African and Ugandan participants. The second study included 2,629 women in Sub-Saharan Africa, and found the rate of infection for those using the dapivirine rings decreased by 27 per cent compared with those given placebo rings. However, the prevention rate was higher among women aged over 21, at 61 per cent, as they were more inclined to use the ring more often and return every month to have it replaced. In both studies, the ring offered no significant protection to those under 21. HIV remains one of the great global health challenges. According to WHO, almost 37m are living with the disease, over half of whom are women. Previous trials haven't been as successful, as they involved antiviral pills and vaginal gels, which weren't used as frequently by the women. The silicone ring doesn't require any additional medication or procedures apart from the initial insertion and monthly replacements. As the New York Times notes, a reason why the ring was popular is because it doesn't require the women to have their partner's permission or cooperation to use it. Men can refuse to wear condoms, prevent their partners from taking antiretroviral pills or using vaginal gels, all of which would also reduce rates of HIV infection when used properly. During the trials, dapivirine levels were measured both in the women's blood and silicone ring to see if they had been used as instructed. This is incredibly important as dapivirine was only effective when the ring was used at all times. The researchers said they will investigate why the ring wasn't effective for those under 21, while also looking into potential uses of the ring to carry other forms of treatment, such as contraception. › In defence of the BBC’s revival of Are You Being Served? Emad Ahmed writes about science and gaming. He tweets @ThisIsEmad. Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!