Condoms and HIV: The Facts In the UK today around 25% of people who are living with HIV don’t know that they have the virus and remain untested. How do we know that? Anonymous Surveys FactSheet. With this many people remain untested and unaware that they have HIV and are potentially putting others at risk of contracting the virus. There is no cure for HIV and the treatments that are available can have unpleasant side effects on your body. Always use a condom when having penetrative sex, it is the only way to protect yourself against HIV when having sex. You may want to use a condom when you have oral sex although the risk of HIV transmission is lower. Talking to your partner(s) is the key to good condom use, from the initial chat about using them to putting them on. It doesn’t need to be a separate thing, it should be part of the fun!