It is hard to remember when AIDS was just a simple epidemic disease. Long ago it exploded into a global rallying cry for ideologues of every stripe, politicizing the science and the social science alike. A small army of academics and consultants now stake careers - and millions of international aid dollars - on specific and often conflicting theories of how to reduce behavioral risks for acquiring and transmitting HIV.
Amid the partisan babble, Helen Epstein has for years generated some of the most sensible commentary around, posting dispatches from AIDS-afflicted countries in Africa to The New York Review of Books and other publications. As a scientist morphed into a journalist, Epstein combines an understanding of the biology of AIDS with a coolly impartial view of the political and social landscape of Africa. She has assembled more than a decade's worth of reporting into an enlightening and troubling book.
It is a testament to the book's strength that the one scientific goof she makes actually matters relatively little. AIDS drugs, Epstein says, will never prove the salvation of infected Africans, as they have Westerners, because "HIV mutates and soon becomes resistant to one or all of the cocktail drugs. Therefore, patients must eventually switch to a new cocktail" - and the second-line drugs for this purpose are likely to be unavailable in Africa for years.
Her statement about drug resistance is incorrect. Although resistance does occur and may turn out to be a particular problem in Africa, it is by no means an inevitable outcome of treatment. Studies indicate that antiretroviral drug combinations, used correctly, work about as well in Africa as anywhere else and are just as likely to induce a permanent remission.
That said, however, Epstein's basic point is quite true: the drugs alone will never save Africa. Prevalence and transmission rates are too high, the health care infrastructure is too weak, there are too many other threatening diseases, and the costs are impossible. Instead, experts agree that hope lies in a still-distant vaccine, and in the "invisible cure" of Epstein's title: dramatic behavioral changes to prevent new infections.
But the problem lies in achieving those changes in cities where almost half the adult population is infected, where rampant poverty turns sex into a form of currency, and children orphaned by AIDS grow up in a chaos that may render them particularly vulnerable to becoming infected as adults.
Interrupting this perfect storm requires a clear understanding of its origins, and we still cannot fully explain why heterosexually transmitted HIV exploded in Africa while remaining confined to very specific communities in the West. Theories abound, and Epstein does a nice job of reviewing them.
The fiction that Africans are more "promiscuous" than Westerners has been disproved; studies have found that Africans often have fewer sexual partners during their lifetime than Westerners do.
But accepted patterns of sexual activity seem to have ignited the tinderbox in Africa. Sex there crosses social boundaries more often than in the West, and the habit of having concurrent partners - simultaneous long-term relationships in which friendship and trust may thwart routine condom use - means a single person's infection may spread rapidly through a group.