Would you exchange the herpes virus, a variant of which you probably already carry, to erradicate HIV? An experimental vaccine could potentially swap one virus for another - well not really swap, more like use one virus to eradicate HIV.

The vaccine works with Cytomegalovirus (CMV) which is a member of the herpes family, interestingly enough the majority of adults already carry CMV and aren't aware because it remains in a dormant state for most of our lives. With the help of this virus this new vaccine is able to track down HIV throughout the body and wipe it out.

In animal studies, monkey's specifically, those who received the vaccine cleared HIV from their bodies and a year later even the most sensitive tests show no example of the virus in their bodies.

Study leader Dr Louis Picker, from Oregon Health & Science University's Vaccine and Gene Therapy Institute, said: "The next step in vaccine development is to test the vaccine candidate in clinical trials in humans. For a human vaccine, the CMV vector would be weakened sufficiently so that it does not cause illness, but will still protect against HIV."