Professor Francoise Barre-Sinoussi who was awarded a Nobel Prize for her work identifying HIV says the Pope should do more to encourage the use of condoms to prevent the spread of the virus that causes Aids.
In 2009, she wrote an open letter to him urging a change of stance by the Catholic Church. The church did slightly relax its line but she says it needs to go further.
Nobel winning Barre-Sinoussi optimistic about HIV cure
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