Three years ago, church leaders in Malawi told 15-year-old Maureen Phiri to stop taking the medicine that she needed to control her HIV infection. "Just believe in God," they told her confidently.
Within a year, the teenager was so ill that she was in hospital. Today she is an advocate for those with HIV, often battling with religious or rural leaders who still deny that the virus is a threat. "There's no HIV here," one village chief told her at a meeting. "We argued for hours," she recalls.
Despite dramatic progress in the global fight against HIV and AIDS, massive challenges and misunderstandings still remain, especially in Africa. On the eve of World AIDS Day on Sunday, experts are assessing the fight against the disease – and finding worrisome gaps and weaknesses.
Globally, the number of AIDS-related deaths has dropped by a remarkable 29 per cent since 2005. Access to antiretroviral drugs has expanded more than 40-fold worldwide in the past decade, and the number of new HIV infections has dropped by 33 per cent in the same period.
Yet last year an estimated 1.6 million people died of AIDS-related causes, and most were Africans. Here's a summary of some of the key remaining challenges in the struggle.
Treatment and prevention efforts are increasingly focusing on adolescents such as Ms. Phiri, since they are more vulnerable than most. Since 2005, there has been a 50 per cent rise in AIDS-related deaths in the 10 to 19 age group, the only demographic group with such a huge increase.
One factor is the ignorance, denial and cultural stigma that still surround HIV and AIDS in many parts of the world, as Ms. Phiri has discovered. Schools are often reluctant to distribute condoms or educate children about the virus. In most African countries, children cannot be tested for HIV without the permission of their parents, which discourages many from getting tested.
South Africa, which has the world's largest number of people living with HIV, recently witnessed a political clash over whether to distribute condoms in schools. The health minister wanted a national plan to distribute condoms in schools, but the education minister disagreed with the plan, so it's now left up to individual schools.
In some countries, experts say, there is a growing complacency over the AIDS crisis, partly because people have greater access to antiretroviral drugs. "They don't have the same siege mentality," said Mbulawa Mugabe, a senior UNAIDS director for southern and eastern Africa.
In key countries such as South Africa, the majority of those who get tested or treated for HIV are women. Of those who receive treatment in South Africa, only about 40 per cent are men, and only about 30 per cent of those who get tested are men.
The trend across Africa is similar, studies have found, with men more likely than women to interrupt their treatment or drop out. This could jeopardize wider efforts to prevent HIV, since men who don't know their HIV status are less likely to use condoms and more likely to have multiple sexual partners and become ill or die.
"Too many men are being left out of HIV services," said a statement this week by Bafana Khumalo, co-founder of Sonke Gender Justice Network, a South African organization working on HIV and gender issues.
"In South Africa and globally, we need campaigns that encourage men to value health-seeking, rather than seeing it as a sign of weakness," he said.
In many African countries, there are serious shortages of HIV medicine, despite a huge expansion of supply in the past decade. South Africa today has the world's biggest HIV treatment program, with 2.4 million people on antiretroviral drugs. Yet a new national survey, released this week, found that one-fifth of its health clinics are suffering shortages of the life-saving medicine.
The survey, the largest of its kind ever conducted, suggests that about 420,000 South Africans could be affected by the shortages.
On average, the supply problems last for 30 days, and patients are often sent home without the medicine they need, the survey found.
These kinds of disruptions in HIV treatment "may ultimately lead to more drug resistance, illness and death," said the Treatment Action Campaign, a leading HIV treatment advocacy group in South Africa.
"For hundreds of thousands of people, this is a dangerous waiting game."
Crisis in poorer countries
While countries such as South Africa and Malawi have dramatically improved their HIV treatment programs in the past decade, many other African countries are too poor or disorganized to provide treatment to those who need it.
Some of the worst crises are in Nigeria, Guinea, South Sudan and the Democratic Republic of the Congo. Although their HIV rates are lower than most countries in southern Africa, their governments are failing to provide treatment to most people who have the virus.
It's a tragic echo of the crisis in South Africa before the arrival of antiretroviral drugs a decade ago, experts say. "We feel like we're in a time-warp," said a statement by Médecins Sans Frontières (Doctors Without Borders).
"We often see people arrive at our hospital when they are already critically ill with full-blown AIDS," said Maria Machako, a doctor at an MSF hospital in Kinshasa, the capital of Congo.
"For many people, it's too late and they are literally dying on our doorstep; 25 per cent do not survive," she said.
"Access to testing and treatment is fatally low for those in need, while stigma is high throughout the country."