Effective HIV prevention requires knowledge of the structure and dynamics of the social networks across which infections are transmitted. These networks are most commonly comprised of chains of sexual relationships. Whereas network data have long been collected during survey interviews, new data sources have become increasingly common in recent years. In this article, we review current and emerging methods for collecting HIV-related network data, as well as modelling frameworks commonly used to infer network parameters and map potential HIV transmission pathways within the network.
We would like to invite you to the Results Showcase for the Sexual Behavior Survey on Friday, 27 March, 2015 from 11am – 3pm at the Blue Hall in Khayelitsha.
Loss to follow-up (LTFU) is a serious problem in most sub-Saharan African ART programmes. If ART is interrupted or reduced, HIV again progresses, and this increases the risk of opportunistic infections and, ultimately, AIDS and death. In addition, the viral load of a patient who interrupts ART will rebound, and the probability of onward transmission increases. If tracing programmes can accelerate the return of lost patients, these patients may be less likely to transmit the virus, since the period of lapsed treatment is shortened. In this study, we created a mathematical model to determine whether tracing patients LTFU from ART programs would lower the rate of HIV transmission.
Young women in relationships with older men are typically at an elevated risk for acquisition of HIV in sub-Saharan Africa. Most qualitative studies have tended to focus on why women are motivated to participate in these relationships, offering little insight into perceived risks of these relationships. Therefore we conducted a qualitative study in three urban communities in Cape Town using thematic content analysis to explore women’s perceived risks of (non-)age-disparate relationships, the benefits of dating older men, and risk perceptions that influence decisions around these relationships.
Population-type models, accounting for phenomena such as population lifetimes, mixing patterns, recruitment patterns, genetic evolution and environmental conditions, can be usefully applied to the biology of HIV infection and viral replication. A simple dynamic model can explore the effect of a vaccine-like stimulus on the mortality and infectiousness, which formally looks like fertility, of invading Read More
The publication in May, with much fanfare, of the results of the HPTN 052 Randomised Control Trial of when to start HIV-positive people on ART was music to SACEMA’s ears. The trial involved HIV discordant couples. In the treatment arm, the HIV positive partner was started immediately on anti-retroviral therapy (ART); in the control arm, people were started on ART when their CD4 cell count fell below 250/µL, as currently advised by the World Health Organization. The study showed that early treatment cut transmission by 96% and the incidence of tuberculosis by 82%. Now that it is beyond dispute that treatment dramatically reduces individual infectiousness, the remaining concerns about Treatment as Prevention are operational, since we now need to determine how such large treatment programs be safely and effectively managed, and cost, since this would require a substantial up-front investment even though it will be cost-saving in the long run.