(Viking, £9.99)
Almost 30 years into the biggest global infectious disease epidemic in history, we still don't know what works practically in Aids prevention. Billions of dollars, pounds, yen and euros have been spent and we now have anti-retroviral therapies for people who have been diagnosed with Aids. But on prevention, we have very little in the armoury.
In early August, the 17th International Aids Conference is being held in Mexico City. If the 2006 Toronto conference is anything to go by, Mexico will attract as many as 30,000 delegates. Serious science and medicine will be interspersed with plenary sessions by star presenters from the worlds of science, politics, the arts and the UN: a mix of seriousness and razzmatazz akin to a US presidential convention.
A world away from this, in early 1995 I was talking with Rajiv, a middle-aged man, on the veranda of a shabby dhaba, owned by his father, on one of the hectic main transport routes running through Rajasthan in northwestern India. Dhabas are refreshment and overnight (and therefore sex) stops for thousands of truckers whose vehicles thunder along India's roads in a cacophony of horns, colour and fumes. We discussed why the free condom dispenser—which sat discreetly on the front wall of the truck stop as part of a local NGO's HIV prevention efforts—was empty, and had obviously been so for a long time. Rajiv was clearly embarrassed to explore this with me, saying I should speak to his father. Adopting a stern expression, the older man explained: "I keep these things in a drawer in my desk; I don't give them to just anyone. I must know they are respectable. I am not wasting India's national wealth on these things." In July 2001, another old man, the then president of Kenya, Daniel arap Moi, made a speech to the Kenyan Pharmaceutical Society. He was, he said, reluctant to spend money on importing condoms to protect Kenyans from contracting HIV, because it was better for Kenyans to refrain from sex, "even for only two years."
These two views about prevention contain more sense than they might at first appear to, according to Helen Epstein, journalist and author of one of the best recent books on the HIV/Aids epidemic (just out in paperback). Her argument is as follows. The extreme forms of heterosexually transmitted HIV epidemics observed in some parts of Africa reflect high levels of concurrent sexual partnering, particularly in the eastern and southern parts of the continent. A newly infected person experiences a flu-like illness within a few weeks of infection, the result of the large viral population in their body and their immune system's attempt to fight the invader. During this period of high viraemia, a person will recover from the initial illness and resume their ordinary life (although in the end, their defences will fail). But because of the elevated viral population, if they have sex at this time they are very likely to infect their partner. If they have more than one partner, the chances of infection are high for each one of those partners and subsequently for others in their extended sexual network. If other sexually transmitted infections are also present, the probability of transmission increases hugely. This is the concurrency problem that forms Epstein's central argument: HIV hyper-epidemics are not about numbers of partners, but about the distinct epidemiological process of concurrent partnering.
The prevention target should therefore be to stop the overlapping relationships which allow people with peaks of viraemia to pass on their infection to several partners within a brief timespan. Epstein and others suggest that this African pattern of behaviour differs from the sexual partnering common in the US and Europe where, while the lifetime number of sexual partners may be quite large, they are more likely to be sequential rather than concurrent. And the underlying causes of this high-risk environment relate to what Epstein calls "the African earthquake," whereby "the Aids epidemic in Africa has been triggered by one of the most rapid social and economic transitions in world history, from an agrarian past to a semi-urbanised present. For millions of African people, an entire way of life, with all its roots and certainties, has been lost in a few generations. The resulting upheavals in social life have generated an earthquake in gender relations that has opened wide channels for the spread of HIV." (There may also be another factor at work in these African hyper-epidemics. Very recent research suggests that some African populations may have a higher susceptibility to HIV as a result of particular cellular evolutionary adaptations developed to resist that 5m-year-old companion of humans: the malaria parasite.)
Why has it been so hard for HIV/Aids policymakers to focus on the problem of concurrency? There are three interlinked reasons. The first is a politically correct over-reliance on the "condom solution"; the second is the transfer of prevention strategies from the gay epidemic in the US to a very different situation in Africa; the third is the way that other concerns, from poverty alleviation to threats to global security, have been hung on the HIV/Aids epidemic as a means of raising funds.
First, the fallacy of the condom. It is obvious that a barrier method prevents transfer of the virus. Condoms have been very important in reducing transmission in heterosexual and homosexual epidemics in rich countries. Of other countries to have reduced the spread of HIV, only Thailand's success can be clearly attributed to widespread condom use—and this required high-level government support. Even so, as of 2007 Thailand had an estimated cumulative total of 1.1m infected people since the beginning of its epidemic.
Despite the resources devoted to condom distribution in Africa over the last 28 years, there have never been enough of the things, and people have been very reluctant to use them. (Vatican opposition has also been a factor.) UNAids estimates that 13bn condoms per year are needed to help halt the spread of HIV and other sexually transmitted infections. Actual distribution has never come near to meeting this target. In 2004, some 2.1bn condoms were provided by various donors. In that year, sub-Saharan Africa received about ten condoms per man of reproductive age (15-59). And while some large countries like Brazil, China and India are self-sufficient in condoms, for many poor countries, the gap between condom needs and donor support means paying for imported condoms with funds diverted from medicine and other necessities.
The first identified outbreaks of HIV were among gay men in the US and western Europe in the early 1980s. In this highly motivated group, condoms were a key component of an effective response. Men who have sex with men were familiar with the technology, they had few moral or ideological scruples about using condoms, and, if they were to continue with the "bath-house" culture of the 1970s, condoms were clearly the way to go.
Family planning for poor countries was also big business at that time, and it seemed sensible to transfer the condom strategies and targets of the numerous family planning groups into HIV prevention. It also helped keep these organisations in business. But UNAids estimates there are now around 22.5m people living with HIV/Aids in sub-Saharan Africa, accounting for almost a third of all new global HIV infections and Aids-related deaths. In 2005, HIV prevalence exceeded 15 per cent among women aged 15 to 49 attending ante-natal clinics in Botswana, Lesotho, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe. In some countries, prevalence nudges or even exceeds 30 per cent of this age group.
So condoms have not worked in Africa. Other strategies which could have been tried have remained underfunded. These include the development of vaginal microbicides, which could be controlled by women, and male circumcision—which seems to offer protection of at least 60 per cent efficacy. Men are now reportedly queuing for circumcision in parts of southern Africa. In some clinics in Swaziland, demand has reportedly increased a hundredfold in a few months.
You need spend only a short period in poor rural and urban communities in Africa to understand some of the reasons condoms did not work well for heterosexual people there: crowded living accommodation shared with children, embarrassment about sex and, perhaps above all, the problem of buying condoms in small, close-knit communities where the local shop proprietor may be your uncle—or even your lover's husband. There is also a disposal problem when flushing toilets are rare and goats and other domestic animals may choke on a casually discarded condom. Other reasons people don't like them include beliefs about the nature of sexual pleasure, the role of semen in sorcery and the importance of fecundity. In other words, what worked for men in San Francisco or Brentwood did not work for men and women in Harare, Johannesburg, Gaborone or Nairobi.
But there are other reasons HIV prevention strategies have failed in Africa, centring on the politically correct consensus that nothing specifically "African" can be singled out for criticism. Talk about aspects of African sexual behaviours, and you run the risk of being labelled a racist. Humble people have been ignored because what they said appeared to endorse conservatives' agendas in the US, where the so-called "culture wars" led to worries about stigma and an emphasis on individual human rights—concerns inappropriate to African conditions and rocketing levels of infections. Many of those raising money for prevention in the west have also felt obliged to peg their fundraising to "appropriate" explanations for the disease and fears of its consequences. So HIV epidemics are variously said to be caused by poverty, spread by military forces, and a threat to US national security. The evidence for any of these is at best ambiguous.
HIV/Aids has irrevocably altered the history of parts of Africa. And Epstein shows us how the spread of the disease has been made worse because of the fallout from a cultural conflict thousands of miles from the sites of the suffering. Rapid travel, urbanisation and ever-increasing population-mixing across the globe all have profound implications for infectious diseases in general, whether human or animal, new, emergent or resurgent. Recent examples include BSE and blue-tongue in Britain, West Nile fever on the eastern US seaboard, Legionnaires' disease, avian influenza and the threat of a human influenza pandemic. The lesson of Epstein's book is more generally relevant in these times. It is: ideology and political correctness are bad for public health.