(U-WIRE) LOS ANGELES – AIDS is way hip this summer.

Well, sort of. The public attention focused on the issue by folks like Bono and Angelina Jolie reached an apogee last month when Vanity Fair, arguably the country’s most influential journal of fashion, published its first-ever Africa issue, detailing in full gloss the continent’s challenges with the disease.

This is all splendid. AIDS is horrible, and this action is inspiring. At the same time, however, some key facts are getting lost amid the glitter, specifically those concerning the relationship between poverty and the incidence of HIV infections.

The truth is, in many African countries, you’re less likely to be infected if you’re poor. In fact, there’s evidence to show that increasing people’s incomes in these nations will lead to more HIV infections, not fewer. AIDS, therefore, is not as simple as ending poverty, despite what many awareness campaigns intone.

When you compare HIV infections across countries, it’s easy to draw the conclusion that AIDS is a disease of poverty. Indeed, the latest data from the U.N. AIDS agency show that among the world’s 39.5 million HIV infections, the overwhelming majority are concentrated in the developing world.

Cross-country comparisons do little to explain the dynamics of the AIDS epidemic within countries. Recent nationally representative surveys from Kenya and Tanzania find that HIV incidence actually increases with household wealth. Additionally, among African countries, those with highest incidence rates are also among the richest. Botswana, with its soaring economic growth, is often lauded as an African “miracle;” it had a 24.1 percent incidence of HIV infection among adults in 2005, one of Africa’s highest.

In a particularly puzzling example, Zimbabwe, whose government in the past decade has flown the economy into a recessionary tailspin, has at the same time made massive inroads against AIDS. The country is currently experiencing one of Africa’s only declines in HIV prevalence, despite a depression and the receipt of only one-tenth the foreign aid received by Botswana.

So what’s going on? The answer has to do with concurrency, which is the unique way Africans are likely to carry on sexual relationships. The concept is the subject of a new book, “The Invisible Cure,” by Dr. Helen Epstein. Contrary to the declining myth, Africans are no more promiscuous than Westerners. Epstein presents data showing that Africans have fewer partners over their lifetimes than Americans, and are no more likely to visit sex workers. The problem is that Africans are more likely to carry on multiple long-term relationships at one time. A man has a wife, but also a girlfriend. His wife and girlfriend, in turn, are also likely have their own paramours.

This practice, Epstein argues, is the reason HIV has spread so rapidly in Africa and not in other regions, where monogamous relationships are the norm. Just imagine, that our man above becomes infected with HIV. Without contraception, his two lovers will soon be infected, and they will soon infect their lovers, and so on. If he and his wife were monogamous, the infection would stay confined to the couple, and the disease would spread more slowly.

Concurrency explains the correlation between income and HIV incidence simply: “Having a lot of girlfriends … you’ve got to have a degree of disposable income,” said Godfrey Woelk, an epidemiologist at the University of Zimbabwe, in a recent Washington Post article. “Being poor and being in love does not really work, no matter what the romantics say.” Since the economic downturn, the article says, men there report fewer relationships.

Epstein argues that the key to fighting the spread of AIDS is reducing the number of partners people have. Unfortunately, research shows that increasing incomes may very well do the opposite. If Africa is to get richer, as Bono, Jolie and I urgently want it to, anti-AIDS policy will have to take this finding into account. This is not to be pessimistic.

Community-led prevention campaigns which promote male circumcision – now shown to drastically decrease transmission rates – condom usage, and the “zero grazing” idea of having one partner only, have had successes. We just need to remember that with economic growth, such programs are up against a powerful incentive not to comply.