As African countries scale-up couples HIV testing, little is known about sexual behaviors and HIV risk for HIV-uninfected partners in known HIV-serodiscordant relationships.
We conducted a prospective study of 3380 HIV-serodiscordant partnerships from 7 African countries. Self-reported sexual behavior data were collected quarterly from HIV-uninfected partners.
The proportion of HIV-uninfected partners reporting sex with their known primary HIV-infected partner decreased during follow-up (from 93.5% in the prior month at baseline to 73.2% at 24 months, P < 0.001). Simultaneously, an increasing proportion reported sex with an outside partner (from 3.1% to 13.9%, P < 0.001). A small proportion (<5%, stable throughout follow-up) reported sex with the infected partner and an outside partner in the same month (concurrent). Unprotected sex was more common with outside partners than with their primary known HIV-infected partners (risk ratio 4.6; 95% confidence interval: 4.2 to 5.2). HIV incidence was similar for those reporting sex only with their primary HIV-infected partner compared with those who reported an outside partner (2.87 vs. 3.02 per 100 person-years, P = 0.7), although those who had outside partners were more likely to acquire HIV that was virologically distinct from that of their primary partner (P < 0.001).
For uninfected members of HIV-serodiscordant couples, sex with the infected partner declined as sex with outside partners increased, likely reflecting relationship dissolution and risk shifting from a known infected partner. Risk-reduction messages for HIV-uninfected partners in serodiscordant partnerships should include strategies to reduce HIV acquisition from outside partners.
*Department of Global Health, University of Washington, Seattle, WA
†Department of Medicine, University of Washington, Seattle, WA
‡Department of Epidemiology, University of Washington, Seattle, WA
§Statistical Center for HIV/AIDS Research and Prevention, Fred Hutchinson Cancer Research Center, Seattle, WA
‖Department of Medicine, Indiana University, Indianapolis, IN
¶Department of Obstetrics and Gynecology, University of Nairobi and Kenyatta National Hospital, Nairobi, Kenya
#Center for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya
**Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, San Francisco, CA
††Wits Reproductive Health and HIV Institute, University of the Witwatersrand, Johannesburg, South Africa
Correspondence to: Jared M. Baeten, MD, PhD, University of Washington, 325 Ninth Avenue, Box 359927, Seattle, WA 98104 (e-mail: firstname.lastname@example.org).
Supported by The Bill and Melinda Gates Foundation (grant #26469) and the US National Institutes of Health (National Institute of Allergy and Infectious Diseases grant R01 AI083034).
The authors designed and executed the study, had full access to the raw data, performed all analyses, wrote the article, and had final responsibility for the decision to submit for publication.
The authors have no conflicts of interest to disclose.
Partners in Prevention HSV/HIV Study Team members are listed in Appendix I.
Received June 10, 2011
Accepted September 13, 2011