Johanna Satekge was pregnant with her first-born when she tested positive for HIV in South Africa's Limpopo province in 2000.
When her son was born, he weighed 3.6 kg. When he died seven months later, he had wasted away to 2 kg.
After three years, Satekge got pregnant again, this time giving birth to a daughter she named Blessing.
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"She was healthy, I breastfed her. Then she got ill and died after seven months," said the 39-year-old, taking out her wallet to show Blessing's photo.
"You can see how painful it was. Losing those children was not easy for me. Seeing those tiny babies die before me was really unbearable," she told the Thomson Reuters Foundation in an interview in London ahead of World Aids Day.
Satekge does not know for sure how she contracted HIV but believes it may have been the result of being raped in her 20's.
She was woken up one night by noises in the tin shack she shared with her family.
"I realised there was someone in the house and when I started to scream, he took out a gun," she said. "He was not alone, there were three. I was raped and they ran away."
After reporting the attack to the police, Satekge was tested for HIV. Her result was negative, but no one urged her to get tested again and she was not given post-exposure prophylaxis (PEP), a course of anti-HIV medication, which, if administered early enough, can prevent infection.
A decade on, Satekge is a mother again, to a son whose name, Lefa, means "wealth" and a daughter, Tiisetso, meaning "courage". Both were born without HIV.
After losing Blessing, Satekge started taking antiretroviral drugs which help prevent HIV being passed on to others. When her viral load – the presence of HIV in the blood – was so low as to be undetectable, her doctor encouraged her to start a family.
Now Satekge advises other HIV-positive women on how to prevent the transmission of the virus that causes Aids to their children.
58 percent of HIV positive in sub-Saharan Africa are women
Women account for 58 percent of those with HIV in sub-Saharan Africa, which is also home to 85 percent of pregnant women with HIV, according to UNAIDS.
Coverage of services to prevent mother-to-child transmission of HIV in sub-Saharan Africa has reached 68 percent from 56 percent in 2011, UNAIDS said this week.
It also noted that the number of children newly infected with HIV in the region fell by 43 percent to 210 000 in 2013 from 370 000 in 2009.
Despite this progress, up to 600 babies are infected with HIV in sub-Saharan Africa every day, most of them acquiring it from their mothers during pregnancy, childbirth and breastfeeding, according to charity mothers2mothers (m2m).
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Without treatment, about half of these children will die before the age of two, it says.
For the past five years, Satekge has worked alongside doctors and nurses as an m2m "mother mentor", offering support and health education to HIV-positive mothers and other women in a bid to reverse the trend.
Similar m2m programmes have been rolled out in Kenya, Lesotho, Malawi, Swaziland and Uganda.
HIV Is not inherited
Satekge says there have been big advances in the almost 15 years since her status was revealed.
"It was hard to be diagnosed at that time. You used to see just images of skeletal people," Satekge said.
"My niece, who I was raising, would sometimes come home from primary school, crying: 'How is mama HIV positive? Is she going to die?'"
Even going to church back then offered little comfort.
Punishment from God
"I used to go to church but I stopped after the pastor said HIV is a punishment from God," Satekge recalled.
Now she receives calls from clergymen requesting that she speak to their congregations about HIV.
"The stigma has reduced," she said.
Mothers whose daughters are pregnant seek out Satekge at the clinic where her team sees more than 300 women a month, asking her to advise them to test for HIV. But many hurdles remain.
Less than half of all adults living with HIV in sub-Saharan Africa know their HIV status. Almost 60 percent of people in South Africa do not have access to antiretroviral therapy, according to UNAIDS.
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Young women and girls are disproportionately affected by HIV. HIV infection rates are on average five times higher among girls than boys and sexual violence is a persistent threat.
Success in the fight against the epidemic depends on people like Satekge, who are seen as role models to many.
"I've got meaning," Satekge said. "Every day I say I'm going to work and save somebody's life. My slogan is 'HIV is not inherited'."
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Image: Stop Aids from Shutterstock