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HIV Prevention Knowledge Base

A Collection of Research and Tools to Help You Find What Works in Prevention

Combination Approaches: HIV Prevention for Serodiscordant Couples

I. Definition of the Prevention Area

HIV-serodiscordant couples, in which one partner is HIV-positive and the other is HIV-negative, are now recognized as a priority for HIV prevention interventions.

II. Epidemiological Justification for the Prevention Area

Although there is considerable variation across countries, recent studies in sub-Saharan Africa with mature epidemics show that up to two-thirds of infected couples are discordant. These studies seek to assess the extent to which HIV transmission within marriages was spurred by high infection rates in sub-Saharan Africa due to heterosexual transmission. One analysis estimated that 55 to 92 percent of new, heterosexually acquired HIV infections among adults occurred within serodiscordant marital or cohabiting relationships. Additionally, among discordant couples, only the female partner is infected in 30 to 40 percent of cases, dispelling a common misperception that only men, not women, are the HIV-positive partner.

According to a research review, the following factors make it more likely that a person living with HIV will transmit the virus to his or her partner: the presence of other sexually transmitted infections, particularly genital ulcerative diseases; high viral load; failure to use condoms correctly and consistently; and specific sexual practices such as a high number of sexual partners and higher frequency of sexual contact. Concurrent sexual partnership may also contribute to risk. The risk of transmission is especially high during early infection, when it is estimated to be 26 times more infectious than during later stages of infection. This makes it especially important to identify HIV infection during the acute stage.

Prevention responses also need to take into account the progress of the epidemic. One hypothesis is that in early epidemics, most discordant couples arise due to HIV infection of one partner from a preexisting relationship, whereas in more mature epidemics, a greater proportion of discordant couples initiate relationships with a new partner who is already infected.

III. Core Programmatic Components

HIV prevention programs among discordant couples are traditionally based on three types of interventions: 1) couples HIV voluntary counseling and testingvia both community-based outreach and in antenatal clinics, 2) group-based workshops with serodiscordant couples, and 3) integrated antiretroviral therapy and HIV prevention programs. These programs often include risk reduction counseling, referrals to treatment, counseling on family planning, and an avenue to further care and support services.

Couples HIV counseling and testing is the cornerstone of many discordant couple interventions; it remains the only way to identify couples in which one partner is HIV-positive and one is HIV-negative. New and innovative methods are being developed to increase uptake of couples counseling and testing as many individuals and couples do not know their status. To increase HIV testing among couples, couples testing programs will likely require integration with broader HIV programs including care, treatment, and support services; mother-to-child-transmission programs; male circumcision; condom promotion; partner reduction; and other behavior change interventions.

Effective prevention programming is necessary for serodiscordant couples, targeted both to the couple and to the individuals. One study showed that the HIV-negative partner increased their number of outside sexual partners after learning the HIV-positive status of their partner. Campbell et al. confirms this result, showing that about 27 percent of seroconverters in serodiscordant couples in the study were infected by an outside partner.

New advances in the biomedical field have demonstrated success in reducing HIV transmission among discordant couples, namely pre-exposure prophylaxis and antiretroviral therapy as prevention. These prevention methods are still under development, and their real-life applicability is currently being reviewed, but they could prove to be valuable prevention methods in the future.

IV. Current Status of Implementation Experience

Programs in developing countries aimed at reducing transmission of HIV in discordant couples are too new to evaluate for effectiveness. To date, interventions have largely been conducted within structured research protocols, so it is still uncertain whether the efficacy of such interventions will work in real-life settings, and whether such interventions can be scaled up to achieve sufficient reach to reduce overall rates of HIV transmission.