It's a tale of culture, geography, economics, colonial legacies, scientific advances, and now the idea that we have to prevent cases and treat patients one at a time
Sub-Saharan Africa only has 12.5 percent of the world's population but, last year, 70 percent of its new HIV infections (1.9 out of 2.7 million) and 67 percent of its AIDS-related deaths (1.2 out of 1.8 million). Two in three HIV-positive people live in Sub-Saharan African (22.9 out of 34 million). Of the approximately 250,000 children under age 15 who died of AIDS-related causes last year, 90 percent were Sub-Saharan African.
Today, as this year's UN World AIDS Day report emphasizes, the global fight against AIDS focuses overwhelmingly on Sub-Saharan Africa, where it is making real progress. Since 1997 -- the peak of the world AIDS crisis -- the number of new HIV infections has dropped 21 percent worldwide and 26 percent in Sub-Saharan Africa. The number of new HIV infections globally has leveled off in recent years, but the worst afflicted countries are doing better at slowing the virus's spread, which bodes well for reducing infection rates in the future. In the meantime until we get to global zero, we're getting better at treatment: the number of AIDS-related deaths is still dropping as treatment improves in poor or remote communities.
Factors like poverty and education play a role in Africa's AIDS epidemic, but it's more than that. A Sub-Saharan African is still five times as likely to have HIV as likely as someone from the Caribbean, the region with the second highest prevalence rate; 12 times as likely as a Latin American; 17 times as a South or Southeast Asian; and 25 times as a Middle Easterner or North African. The AIDS crisis is global, but it is in many ways an African story. The more people in a given community are infected the more likely than a healthy member of that community will in turn be infected, which is part of what makes Africa's crisis so hard to turn back.
The story of how Africa's AIDS crisis came to be is complicated, controversial, and almost as heavily debated as what to do about it. Since rushing to the continent en masse in the 1990s, researchers have theorized one potential cause after another -- physiology, marriage culture, food practices, poor governance, and on -- all of them backed up by data and many of them convincing. It can be hard to resist the idea that Africa's problem is that it is very unlucky. But there's nothing inherent to Africa that means prevention and treatment can't succeed in rolling back the AIDS crisis, as they already are.
For years, research on Africa's AIDS crisis focused on the behavior of Africans, which has been controversial. Well-meaning scientists, often from the same white European countries that ravaged Africa through colonialism only a century earlier, have struggled to break out of the same stereotypes that enabled and exacerbated the worst colonial practices. Researching AIDS in Africa can be most fraught when it comes to the one human behavior that's perhaps most relevant to the disease but the touchiest to talk about in this or any culture: sex. How, when, and where people have sex can, unsurprisingly, play an enormous role in their exposure to sexually transmitted diseases like HIV. And sexual practices can be enormously cultural.
So it's natural to wonder how or whether African cultural particulars relating to sex might play a role in how AIDS is transmitted there. But that's been a difficult subject for the Westerners who dominate HIV research to bring up in Sub-Saharan Africa. European obsessions with African sexuality persisted right up until the end of the colonial era, which, it's easy to forget, lasted well into many of our grandparents' lifetimes. It wasn't so long ago that Europeans were carving up African genitals for display in museums or lining up for "primitivist" dance performances in black-tie concert halls.
This isn't to say that Western scientists are racist, of course, but it hasn't been easy for them to study African sexual culture without being affected by centuries-old Western stereotypes about Africans. A 2003 paper in Development and Change found, "Western preconceptions regarding African sexuality distorted early research on the social context of AIDS in Africa and limited the scope of preventive policies. Key works cited repeatedly in the social science and policy literature constructed a hypersexualized pan-African culture as the main reason for the high prevalence of HIV in sub-Saharan Africa."
Still, culture influences behavior and behavior influences health. So culture needs to be studied to understand HIV, but as any anthropologist will tell, you can't study someone else's culture without understanding your own and the biases that it gives you. Western AIDS researchers in Africa have a hard job: not only do they have to understand one of the worst health crises since the black plague, they also have to understand how centuries of European-African interactions color their own perception of African culture.
In 1989, the Journal of Health and Social Behavior published a study on how Sub-Saharan Africa's migratory labor economy made it easier for HIV to spread and harder for it to be prevented. African economies' heavy reliance on shifting migrant labor created "long absences, increased family breakdown, and increased numbers of sexual partners." A 1993 New Yorker story focused on the role of truckers in Central Africa, where HIV first spread to humans. Geography and poor governance make Central African infrastructure some of the weakest in the world, which means that truckers are unusually numerous there. Trucking and prostitution typically coincide; the proliferation of the former could likely promote the latter. Because HIV may have spread to humans in Central Africa up to a century before the disease was first studied, it had plenty of time to entrench itself in the group of Africans most likely to transfer the disease.
Studies have also cited higher rates of formal and informal polygamy in Africa, although this idea may be falling out of favor. And non-sexual behavior could play a role. Central Africa's geography can make large-scale agriculture difficult but, in some places, provides a ready source of protein in wild game, including primates. But bush meat, as it's often called, can spread HIV and may have even been its original source. The African AIDS crisis's worst years also came during a period when African governments were at their weakest, most abusive, and most prone to destabilizing internal conflicts, all of which made prevention and treatment much worse.
Over the past decade or so, advances in genetics have led researchers to shift some of their focus away from the AIDS crisis's possible behavioral causes to its physiological causes. In 2008, a paper published in Cell Host & Microbe found that a genetic variation particular to Africans could make them both more susceptible to HIV and slower to show its symptoms, meaning that they are more likely to unknowingly transmit the disease. The genetic variation, the paper suggests, may have developed as a resistance to malaria, the other Africa-ravaging disease. (If the researchers are right, it would be another piece of evidence suggesting it may have been not culture but geography -- Sub-Saharan Africa's wetlands, floodplains, and tropical climates are a paradise for malaria-spreading mosquitoes; African geography also promotes trucking and bush meat, for example -- that made Africa so susceptible to HIV.)
So it's difficult, maybe impossible, to narrow the African AIDS crisis down to a single root cause. For years, this frustrated researchers who wanted to find that one thing -- governance, sexual norms such as number of partners, education about how HIV spreads -- that would fix everything else. One of the big breakthroughs that has so advanced the fight against AIDS in Africa was when everyone seemed to realize that perhaps the best approach, even if it's frustrating and complicated and difficult, is piecemeal. It might not be very satisfying or exciting to launch a thousand tiny programs, but it's what's worked.
The one-at-a-time approach in Africa might be best exemplified by the circumcision programs cropping up in southern Africa over the past few years. Circumcision makes HIV 60 percent less likely to be transmitted during heterosexual sex. It's the kind of program that, during the first years of the crisis, aid agencies and African governments didn't find very exciting: it doesn't prevent infection, it doesn't prevent HIV from turning into AIDS, and it doesn't keep AIDS patients alive. It doesn't solve any problems, but it does manage them. It's the kind of program that aid agencies and African governments -- even the normally dysfunctional Zimbabwean regime -- are now pushing aggressively, because it saves lives.
This is how the world fights AIDS in Africa today: prevent one case at a time, treat one patient at a time. Hand out condoms to sex workers. Simplify drug cocktails. Put posters in schools explaining safe sex and in pre-natal clinics explaining treatment options. Give out more preventative drugs (antiretroviral coverage in Africa increased 20 percent last year alone). In addition to funding research for a cure, agencies have also put a lot of resources into making treatments cheaper: it used to cost $10,000 a year to live with HIV and now it costs $100. Over the past ten years, the prevalence of HIV has declined in 21 of the 24 worst afflicted countries; it's declined by more than 25 percent in five of Africa's worst affected states. In Zimbabwe, the rate of new HIV infections has fallen to one fifth of what it was in 1991.
Bringing together so many regional, national, and local projects has been something of a small revolution in governance for Sub-Saharan Africa, which not long ago was one of the least-governed places in the world. States were frequently at war, both internally and with their neighbors, in a way that would have made today's cooperation on HIV impossible. The United Nations, particularly the UNAIDS mission it launched in 1996, often makes one of the most banal but important contributions: putting African government officials, African civil society leaders, aid agencies, and pharma reps together in a room to coordinate HIV programs big and small.
Still, these small-scale advances do not add up to a cure. But excitement around their accomplishments is leading some AIDS experts to advocate for what they call "treatment as prevention" -- the idea that enough condoms, circumcisions, and education programs could win the war on AIDS. While this one-by-one approach has saved tens of thousands of lives annually in Africa, it's hard to imagine that it could really push the number of HIV cases down to zero. And some critics warn that, by focusing on managing HIV's spread rather than stopping it outright, the world would be giving up on the bigger mission of stamping out AIDS altogether. The debate over "treatment as prevention" can get heated, but it's not the first controversy in the battle against AIDS in Africa, and it won't be the last.
Lois Farrow Parshley contributed research