Measuring and modelling concurrency

This article explores three critical topics discussed in the recent debate over concurrency (overlapping sexual partnerships): measurement of the prevalence of concurrency, mathematical modelling of concurrency and HIV epidemic dynamics, and measuring the correlation between HIV and concurrency. The focus of the article is the concurrency hypothesis – the proposition that presumed high prevalence of concurrency explains sub-Saharan Africa's exceptionally high HIV prevalence. Recent surveys using improved questionnaire design show reported concurrency ranging from 0.8% to 7.6% in the region. Even after adjusting for plausible levels of reporting errors, appropriately parameterized sexual network models of HIV epidemics do not generate sustainable epidemic trajectories (avoid epidemic extinction) at levels of concurrency found in recent surveys in sub-Saharan Africa. Efforts to support the concurrency hypothesis with a statistical correlation between HIV incidence and concurrency prevalence are not yet successful. Two decades of efforts to find evidence in support of the concurrency hypothesis have failed to build a convincing case

Seasonal PrEP for partners of migrant miners in southern Mozambique: a highly focused PrEP intervention

Introduction: To be used most effectively, pre-exposure prophylaxis (PrEP) should be prioritized to those at high risk of acquisition and would ideally be aligned with time periods of increased exposure. Identifying such time periods is not always straightforward, however. Gaza Province in southern Mozambique is characterized by high levels of HIV transmission and circular labour migration to mines in South Africa. A strong seasonal pattern in births is observable, reflecting an increase in conception in December. Given the potential for increased HIV transmission between miners returning in December and their partners in Gaza Province, PrEP use by the latter would be a useful means of HIV prevention, especially for couples who wish to conceive. Methods: A mathematical model was used to represent population-level adult heterosexual HIV transmission in Gaza Province. Increased HIV acquisition among partners of miners in December, coinciding with the miners’ return from South Africa, is represented. In addition to a PrEP intervention, the scale-up of treatment and recent scale-up of male circumcision that have occurred in Gaza are represented. Results: Providing time-limited PrEP to the partners of migrant miners, as opposed to providing PrEP all year, would improve the cost per infection averted by 7.5-fold. For the cost per infection averted to be below US$3000, at least 85$115 per person per year. Uncertainty regarding incidence of HIV transmission among partners of miners each year in December has a strong influence on estimates of cost per infection averted. Conclusions: Providing time-limited PrEP to partners of migrant miners in Gaza Province during periods of increased exposure would be a novel strategy for providing PrEP. This strategy would allow for a better prioritized intervention, with the potential to improve the efficiency of a PrEP intervention considerably, as well as providing important reproductive health benefits

Gender norms and economic empowerment intervention to reduce intimate partner violence against women in rural Côte d'Ivoire: a randomized controlled pilot study.

BACKGROUND: Gender-based violence against women, including intimate partner violence (IPV), is a pervasive health and human rights concern. However, relatively little intervention research has been conducted on how to reduce IPV in settings impacted by conflict. The current study reports on the evaluation of the incremental impact of adding "gender dialogue groups" to an economic empowerment group savings program on levels of IPV. This study took place in north and northwestern rural Côte d'Ivoire. METHODS: Between 2010 and 2012, we conducted a two-armed, non-blinded randomized-controlled trial (RCT) comparing group savings only (control) to "gender dialogue groups" added to group savings (treatment). The gender dialogue group consisted of eight sessions that targeted women and their male partner. Eligible Ivorian women (18+ years, no prior experience with group savings) were invited to participate. 934 out of 981 (95.2%) partnered women completed baseline and endline data collection. The primary trial outcome measure was an overall measure of past-year physical and/or sexual IPV. Past year physical IPV, sexual IPV, and economic abuse were also separately assessed, as were attitudes towards justification of wife beating and a woman's ability to refuse sex with her husband. RESULTS: Intent to treat analyses revealed that compared to groups savings alone, the addition of gender dialogue groups resulted in a slightly lower odds of reporting past year physical and/or sexual IPV (OR: 0.92; 95% CI: 0.58, 1.47; not statistically significant). Reductions in reporting of physical IPV and sexual IPV were also observed (not statistically significant). Women in the treatment group were significantly less likely to report economic abuse than control group counterparts (OR = 0.39; 95% CI: 0.25, 0.60, p < .0001). Acceptance of wife beating was significantly reduced among the treatment group (β = -0.97; 95% CI: -1.67, -0.28, p = 0.006), while attitudes towards refusal of sex did not significantly change Per protocol analysis suggests that compared to control women, treatment women attending more than 75% of intervention sessions with their male partner were less likely to report physical IPV (a OR: 0.45; 95% CI: 0.21, 0.94; p = .04) and report fewer justifications for wife beating (adjusted β = -1.14; 95% CI: -2.01, -0.28, p = 0.01) ; and both low and high adherent women reported significantly decreased economic abuse (a OR: 0.31; 95% CI: 0.18, 0.52, p < 0.0001; a OR: 0.47; 95% CI: 0.27, 0.81, p = 01, respectively). No significant reductions were observed for physical and/or sexual IPV, or sexual IPV alone. CONCLUSIONS: Results from this pilot RCT suggest the importance of addressing household gender inequities alongside economic programming, because this type of combined intervention has potential to reduce levels of IPV. Additional large-scale intervention research is needed to replicate these findings. TRIAL REGISTRATION: REGISTRATION NUMBER: NCT01629472