Oct 2, 2006, Damien de Walque
|New research findings on discordant couples—where only one of the two partners is infected with HIV/AIDS—is challenging pervasive assumptions about the determinants of HIV/AIDS transmission to the general population in Burkina Faso, Cameroon, Ghana, Kenya, and Tanzania.|
Recent research on discordant couples (where only one of two partners is HIV+) in five African countries—Burkina Faso, Cameroon, Ghana, Kenya and Tanzania—presents two surprising findings that challenge conventional notions about HIV transmission: first, that in at least two-thirds of HIV-infected couples, only one partner is infected, and second, that in many such couples, only the woman is positive. These findings have very important implications for HIV prevention policies.
The pervasive, if unstated belief in the HIV/AIDS community is that males, by and large, are primarily responsible for spreading the infection among married and cohabiting couples. In 2004, a U.N. report entitled Women and HIV/AIDS: Confronting the Crisis reported : “Nearly universally, cultural expectations have encouraged men to have multiple partners, while women are expected to abstain or be faithful.” and “Faithfulness offers little protection to wives whose husbands have several partners or were infected before they were married.”
HIV prevention policies should now take into account the fact that partners who are not yet infected are an important target group, and also that women are almost as likely to transmit the infection to their uninfected male partners as men to their uninfected women partners.
The first finding - in two-thirds of HIV-infected couples only one partner is infected
The proportion of concordant positive couples (both HIV-positive) for these five countries is less than one-third (the second column for each country in table 1). This finding suggests that expanding prevention efforts to include partners of HIV-positive individuals may prove helpful in preventing further transmission—for example, by promoting joint voluntary counseling and testing among couples.
The second finding - in a sizeable proportion of HIV-infected couples the woman is the only infected partner
In the five countries studied the fraction of infected couples where only females are infected is between 30 and 40 percent (table 1). These findings challenge the notion that males are the primary channel for HIV transmission from high-risk groups to the general population, and also contradict self-reports of sexual behavior by females.
Self-reported sexual intercourse outside the union among women in cohabiting couples during the last 12 months ranges from 0.7 percent in Burkina Faso to 4.1 percent in Tanzania, and among cohabiting males from 8.7 percent in Burkina Faso to 25.9 percent in Cameroon. Substantial reporting biases in self-reported sexual behavior among men and women have also been reported in earlier studies.[4,5]
This study explores, at great length, potential explanations for the sizeable share of discordant couples where only the woman is infected, including polygyny (marriage to several wives), a bias in the coverage of the HIV testing in the survey, and earlier unions or infections before the current union. These explanations for the most part do not explain the data in these five countries.
In a sample limited to couples where the woman has been in only one union for 10 years or more —which should exclude most case of infections prior to the current union—the proportion of discordant female couples decreases, but only slightly, except in Ghana and Tanzania (table 2). The proportion of discordant female couples in Burkina Faso, Cameroon, and Kenya is still around a sizeable 30 percent of HIV-infected couples.
The percentage of discordant female couples in Ghana and Tanzania decreases to 19.5 and 21.9 percent, respectively, which suggests that infection before marriage might explain some, but not all, of the cases of couples where only the woman is infected.
Certainly for the three other countries, and to a large extent for Ghana and Tanzania, HIV infection before marriage or the union does not explain the sizeable share of discordant female couples. That share is difficult to explain unless women are also sexually active outside the marriage (or cohabiting union).
Sexual intercourse among women outside the marriage (or cohabiting union) may be more common than reported. Or, even if infrequent, women may be more vulnerable to infection during these encounters, for example, because they are less likely to use condoms than single women and married men.
The point of this explanation is not to “blame” cohabiting women or suggest they are as “guilty” as cohabiting men in transmitting HIV/AIDS. The fact that sexual intercourse can, in many cases, be forced on women, should certainly be kept in mind.
Whatever its causes, sexual intercourse outside the union among women increases their vulnerability to HIV/AIDS. Designing prevention efforts for this population of women will not be an easy task given the culture of silence around women’s sexuality in many African countries and the stigma attached to those, and women in particular, with HIV/AIDS.
But to ignore the role that female sexual activity outside the union plays, among the other channels, in the transmission of the epidemic, would be a disservice to women.
This study is based on a very simple analysis using results from HIV tests
The standard approach for analyzing the determinants of the HIV/AIDS epidemic uses aggregate measures at the country or local level, or more recently, individual-level data. The study described here uses individual-level data to analyze determinants of HIV infection among discordant couples, where only one of the two partners is infected.
The analysis—which documents both the contradiction between self-reported female behavior and the proportion of discordant female couples and other examples of discordance in couples about their reported behaviors—suggests that self-reported behaviors are likely to be biased, and that this data must be weighed carefully when designing prevention policies.
It recommends that, whenever possible, prevention efforts be informed by objective measures of HIV status. Fortunately, similar data from upcoming Demographic and Health Surveys in other African countries will further support a closer analysis of discordant couples and the best prevention efforts to help them.
The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the view of the World Bank, its Executive Directors, or the countries they represent.
DAMIEN DE WALQUE is an Economist in the Development Research Group (Human Development and Public Services Team). His research interests include health and education and the interactions between them, and the analysis of the long-term consequences of mortality crises. He is working on evaluating the impact of HIV/AIDS interventions and policies in several African countries. Email c/o: firstname.lastname@example.org
 Damien de Walque, “Discordant Couples : HIV Infection among Couples in Burkina Faso, Cameroon, Ghana, Kenya and Tanzania,” Policy Research Working Paper 3956, World Bank, Washington, D.C., 2006.
 UNAIDS, UNFPA, and UNIFEM, Women and HIV/AIDS: Confronting the Crisis, Geneva, Switzerland and New-York, USA: UNAIDS, UNFPA and UNIFEM, 2004, p. 7 and 16. [http://www.unfpa.org/hiv/women/]
 Susan Allen, Jareen Meinzen-Derr, Michele Kautzman, Isaac Zulu, Stanley Trask, Ulgen Fideli, Rosemary Musonda, Francis Kasolo, Fen Gao, and Alan Haworth, “Sexual Behavior of HIV discordant couples after HIV counseling and testing,” AIDS 17: 733-740, 2003.
 Mark Gersovitz, “The HIV Epidemic in Four African Countries Seen Through the Demographic and Health Surveys,” The Journal of African Economies 14: 191-246, 2005.
 Mark Gersovitz, Hanan G. Jacoby, F. Seri Dedy, and A. Gozé Tapé, “The Balance of Self-Reported Heterosexual Activity in KAP Surveys and the AIDS Epidemic in Africa,” Journal of the American Statistical Association 93: 875-883, 1998.
 Damien de Walque, “Who Gets AIDS and How? The determinants of HIV infection and sexual behaviors in Burkina Faso, Cameroon, Ghana, Kenya and Tanzania,” Policy Research Working Paper3844, World Bank, Washington, D.C., 2006.