(CNN) - At 19 years old she was spotted by a talent agent while engaging in a shouting match with a bank teller in Los Angeles. Since then Charlize Theron has powerfully demonstrated an almost chameleon-like ability to assume the roles she takes on.
Whether it's as a lesbian serial killer in "Monster" or a no-nonsense mission director searching for clues to the origins of mankind in sci-fi hit "Prometheus," Theron has repeatedly proven why she is one of Hollywood's highest-paid women.
But the Academy Award-winning actor has another starring role -- helping prevent the spread of HIV and AIDS in her homeland of South Africa. Despite recent success in combating the disease, around 5.6 million South Africans have HIV.
"We are in a very, very dangerous period right now, because of our successes," says Theron. "South Africa has had a 63 % drop in new infections when it comes to children under the age of 14. It's a huge success to celebrate and we dropped tremendously when it comes to mother-to-child transmission.
"I think a huge misconception is that 60% is ok, and the problem with not having it be 100% and no more new infections, is that the disease will come back rolling again."
Theron recently traveled to the province of Kwazulu Natal as an advocate for The Global Fund, a financing institution that aims to "prevent, treat and care for people with HIV and AIDS, tuberculosis and malaria."
In KwaZulu Natal one in four 15- to 24-year-olds has HIV, according to UNAIDS. Theron believes the key to making a difference lies in empowering African youth at a grassroots level.
"It's festering now in a pivotal group of young girls, between the ages of 15 and 24," she says. "These girls are very, very hard to reach, and if we do not grab that bull by the horns right now ... we're going to see this disease come back and just cause double the devastation that it has."
As part of her work with the Global Fund, the actor attends educational workshops to discuss HIV and the use of antiretrovirals -- the medication used to suppress the disease.
"It's devastating that we can sit today and look at the devastation that this disease is still causing, especially in my country -- in South Africa -- when it's completely preventable," she says.
Born and raised in Benoni, a small town on the outskirts of eastern Johannesburg, Theron relocated to Italy aged 16, then New York a year later, to pursue a modeling career. Much of her time is now spent in the United States but Theron, 38, still identifies herself as an African woman, which she says is where the desire to help comes from.
"(It's) kind of impossible to lose connection to a country where your bones, your skin, your blood, came together. I feel like I am made in this land, no matter where I live or travel."
She adds: "You cannot do this work if it does not come from a personal place or place of passion ... anybody can show up for an event once, but can you come back year after year, can you? I think that kind of investment must come from a deeper place."
The actor -- who is also a U.N. Messenger of Peace -- has consistently used her high profile to push her activism pursuits over the years.
In 2007, she launched the Charlize Theron Africa Outreach Project -- a not-for-profit that has provided mobile health assistance to secondary schools in impoverished areas of South Africa.
"Africans are very proud people in general and have been able to survive on being self-sufficient and innovative and resilient with everything that we had to deal with," she says. "Africans don't just like to look on outside sources to help. We want to be part of the solution."
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