Summary:

- Researchers in South Africa have announced a major breakthrough in HIV prevention. They have developed a new vaginal gel that can significantly reduce the risk of HIV transmission in women.

- The gel, called "tenofovir," works by blocking the virus from replicating and infecting healthy cells. When used consistently, the gel has been shown to reduce the risk of HIV infection by up to 39%.

- This is an important development in the fight against HIV/AIDS, as women are disproportionately affected by the virus, especially in sub-Saharan Africa. The availability of this effective prevention method could save many lives and help curb the spread of the disease.