Policy makers, fellow scientists, media reporters and students are more likely to pay attention to epidemiologists who are able to articulate new research findings through a captivating narrative, a vivid mental picture or a striking infographic. Recent software developments have made it easy to produce web applications and reports that dynamically combine text, mathematical expressions, code chunks and the output of complex computations. The result is that researchers can adopt a more engaging, interactive form of storytelling.
Antiretroviral therapy (ART) markedly reduces the risk of sexual transmission of HIV. This inspired the idea of treatment as prevention (TasP) to reduce population HIV incidence, by reducing the infectiousness of HIV-infected individuals. However, increased infectiousness when treated individuals are co-infected with other sexually transmitted infections (STIs) could potentially undercut the effectiveness of TasP programs. As there is limited knowledge about the impact of STI co-infections on HIV shedding from individuals on ART, this study reviewed all published scientific evidence.
As the world embraces immediate treatment for HIV, the game is not over: stigma and discrimination persist; drug procurement, supply and delivery are failing in many countries; ways must be found to ensure adherence with treatment to keep people alive, minimize resistance and stop transmission; thirty million people will need treatment for the next half-century or until a cure is found. This is an auspicious time to review a few of the many studies that have accumulated over the last fifteen years in support of providing treatment for people infected with HIV as early and as soon as possible
HIV testing is critically important to HIV prevention and treatment. Therefore UNAIDS has called for 90% of all HIV-positive individuals to be diagnosed by 2020. However, there are practical challenges associated with measuring progress towards this target. Many countries simply quote the proportion of adults who report having ever been tested for HIV in national household surveys. In a recent study, we attempted to obtain more accurate estimates of rates of HIV testing in South Africa, by combining survey data and routine testing data from health services. The results suggest that there is likely to be significant bias in self-reporting of past HIV testing. The results also show that South Africa has made substantial progress in scaling up access to HIV testing and counselling, with 76% of HIV-positive adults diagnosed by 2012. However, men and older adults appear to have a relatively low rate of HIV testing.
We assess here the potential effect of expanded HIV treatment for the prevention of AIDS-related deaths. We analyzed the available UNAIDS data to describe AIDS-related deaths, ART coverage and new HIV infections in 30 countries with the highest AIDS mortality burden and compared it with data from eight high-income countries. For illustrative purposes, we also explored the potential impact of reaching international treatment expansion targets in South Africa and Nigeria- two countries with the largest HIV epidemics, but with different trends of AIDS-related deaths over time – through the examination of four treatment expansion scenarios.
The relationship between narrative and paradigmatic thinking in science, at least in the world of natural philosophy and natural history, is crucial and yet seldom explicitly stated and rarely understood. Creativity in science lies primarily in the narrative mode of thinking and it is here that new discoveries are made and new ideas are found. While we should find ways to develop narrative thinking when teaching science we must also ensure that our students develop the necessary skills to manipulate the paradigmatic formulations of their theories.
Prof. Emmanuel Lesaffre of the Leuven Biostatistics and Statistical Bioinformatics Centre, Catholic University of Leuven, Belgium, will be presenting an intensive course on Bayesian analysis of longitudinal studies on 26 and 27 November 2015 at Stellenbosch University. The course will be oriented towards an applied audience with a good knowledge of various regression models.
As I write, our annual clinic on the Meaningful Modelling of Epidemiological Data (MMED) is in progress, so is the 7th SA AIDS conference, and I just returned from a meeting in Geneva how best to provide advice to teams planning to estimate HIV incidence from large household surveys. In short, it seems to be a time to reflect, to reconsider what we are trying to do, and whether we are making any useful contributions. We hope these quarterly epidemiological update offerings are food for thought.
Malaria kills between 70,000 and 100,000 children every year in Uganda. In order to apply successful interventions to eradicate malaria, there is a continuous need to understand the epidemiology and risk factors associated with the disease. The Malaria Indicator Survey (MIS) in 2009 was the first nationally representative survey of malaria conducted in Uganda. The aim of the study presented here was to use this MIS to investigate the distribution of malaria infection in children under the age of 5 years old, as well as to investigate the relationship with selected socio-economic, demographic and environmental factors.
Agent-based modelling, also called microsimulation, is a way of modelling epidemics that is growing in popularity. Instead of the traditional way of modelling using differential equations, an agent-based model consists of, perhaps, thousands of agents, each representing a person, and each behaving according to a simple set of rules. Instead of outputs such as infection and mortality rates being derived from equations, they are derived from the interactions of the agents over many iterations. These models are providing rich insights into the HIV epidemic.