HIV discoverer: 'To develop a cure is almost impossible'

Francoise Barre-Sinoussi, at the International AIDS Society Conference, in Vancouver.

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Vancouver She's the woman who co-discovered HIV in 1983, and won a Nobel Prize for her work. But next month, French scientist Francoise Barre-Sinoussi will retire from her lab.

She spoke with CNN at this week's International AIDS Society Conference, in Vancouver, about activism, the future of HIV and why there's still no cure -- as well as answering questions submitted by our readers on Twitter.

At the beginning, the epidemic was in San Francisco in the gay community. How have you seen this change over time?

The epidemic changed in the gay population, for example, because they were very well informed and starting to protect themselves against the infection. However, we are starting again to see the epidemic starting in the gay population -- at least in a proportion of the gay population in Europe, Australia and United States. I am a little bit worried that we'll start to have the same profile of the epidemic that we were having in the early 80s.