O1-s06.05 Exploring the Potential Impact on Hiv Incidence of a Reduction in Concurrency in Rural Uganda: a Modelling Study

O1-S06.05 Figure 1 The impact of the intervention on HIV incidence in 2020. Conclusions In this setting, interventions against concurrency have the potential to reduce the HIV incidence and may have a higher impact on the incidence of HIV in women than in men. However a large simulated change in behaviour resulted in only a moderate decrease in HIV incidence. This study does not provide strong support for the prioritisation of concurrency as a target for behaviour change interventions. O1-S06.06 PATTERNS AND TRENDS IN CONCURRENCY AND POLYGAMY IN RURAL ZIMBABWE, 1998e2008 doi:10.1136/sextrans-2011-050109.36 F Takavarasha, S Gregson, J Eaton, C Schumacher, P Mushati, G Garnett, C Nyamukapa. Biomedical Research and Training Institute, Zimbabwe Harare, Zimbabwe; School of Public Health, Imperial College London, Harare, UK; Biomedical Research and Training Institute, Harare, Zimbabwe Background It has been suggested that the decline in HIV prevalence in Zimbabwe from the late 1990s may be partly due to reductions in sexual concurrency but little is known about levels and trends in the different forms of concurrency or their association with HIV risk. Methods We use data from four rounds (1998e2000, 2001e03, 2003e05, 2006e08) of a large longitudinal population-based HIV survey to investigate patterns of non-spousal (two or more current sexual partners, at least one of whom is not a spouse) and spousal (multiple spouses but currently no extra-marital sexual partners) concurrency, and associations with prevalent HIV infection in rural east Zimbabwe. Results 15.4% (95% CI 14.4% to 16.5%) of men (17e54 yrs, N1⁄44327) and 1.9% (1.5% to 2.3%) of women (15e44 yrs, N1⁄45148) reported concurrent sexual partners at baseline. 11.7% (10.8% to 12.7%) and 3.7% (3.2% to 4.3%) of men reported non-spousal and spousal concurrency, respectively. Non-spousal concurrency was most common in single (16%) and divorced/widowed (11%) men but was also reported by married men with single (6.5%) and multiple (4%) spouses (Abstract O1-S06.06 figure 1). HIV prevalence is similar in men with (19.2%) and without (19.5%) concurrent partners but is higher in those with concurrent partners after controlling for age (age-adj. OR (aOR), 1.37; p1⁄40.02). However, after excluding non-sexually experienced men, this difference was not statistically significant (aOR, 1.27, p1⁄40.08). Among all men, HIV prevalence was higher for those with non-spousal concurrency (aOR, 1.38; p1⁄40.015) but not for those with spousal concurrency (aOR, 1.26; p1⁄40.2). For women, concurrency (all non-spousal) was 1.9% (95% CI 1.2% to 2.7%) in single women, 0.4% (0.2% to 0.7%) Abstract O1-S06.06 Figure 1 Prevalence of non-spousal concurrency by marital status, Men, 17e54 years.O1-S06.06 Figure 1 Prevalence of non-spousal concurrency by marital status, Men, 17e54 years. Sex Transm Infect July 2011 Vol 87 Suppl 1 A37 Oral Sessions group.bmj.com on October 11, 2017 Published by http://sti.bmj.com/ Downloaded from