Does a Mature AIDS Epidemic Threaten Growth?

This paper models the impact on economic growth of HIV/AIDS when the epidemic is in a mature phase, in contrast with previous studies focused on periods of expansion, as in African countries. Simulations for Honduras, the epicenter of the epidemic in Central America, show that AIDS is not likely to threaten economic growth through either labor or capital accumulation channels; impacts are estimated between 0. 007 and 0. 27 percent points of GDP growth annually for the period 2001-10. Likewise, increasing spending on prevention, public treatment subsidies and treatment access will not jeopardize economic growth prospects. Critical factors that slash economic growth in Africa (such as human capital reductions and shifts in relative skills) are not strong in Honduras.

HIV/AIDS, Security and Conflict: New Realities, New Responses

Ten years after the HIV/AIDS epidemic itself was identified as a threat to international peace and security, findings from the three-year AIDS, Security and Conflict Initiative (ASCI)(1) present evidence of the mutually reinforcing dynamics linking HIV/AIDS, conflict and security

A stochastic multi-scale model of HIV-1 transmission for decision-making: application to a MSM population.

BackgroundIn the absence of an effective vaccine against HIV-1, the scientific community is presented with the challenge of developing alternative methods to curb its spread. Due to the complexity of the disease, however, our ability to predict the impact of various prevention and treatment strategies is limited. While ART has been widely accepted as the gold standard of modern care, its timing is debated.ObjectivesTo evaluate the impact of medical interventions at the level of individuals on the spread of infection across the whole population. Specifically, we investigate the impact of ART initiation timing on HIV-1 spread in an MSM (Men who have Sex with Men) population.Design and methodsA stochastic multi-scale model of HIV-1 transmission that integrates within a single framework the in-host cellular dynamics and their outcomes, patient health states, and sexual contact networks. The model captures disease state and progression within individuals, and allows for simulation of therapeutic strategies.ResultsEarly ART initiation may substantially affect disease spread through a population.ConclusionsOur model provides a multi-scale, systems-based approach to evaluate the broader implications of therapeutic strategies

Children Affected by AIDS: A Review of the Literature on Orphaned and Vulnerable Children

This paper presents a systematic review of the literature pertaining to orphans and vulnerable children in sub-Saharan Africa, with a particular focus on research in countries heavily impacted by HIV/AIDS. Despite study and data limitations, the literature provides evidence of growing orphan-based disparities, difficulties within households providing care, and insufficient capacity among social services. Still, additional research is urgently needed, including better OVC surveillance methods, qualitative data than answers persisting questions, the inclusion of more useful indicators in national household surveys, and longitudinal studies to determine the mechanisms by which parental HIV status and death impacts children, caregiving impacts households, and the orphan epidemic impacts communities and social systems

Resurgence of HIV infection among men who have sex with men in Switzerland : mathematical modelling study

New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis. METHODOLOGY/PRINCIPAL FINDINGS: The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995-1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate. CONCLUSIONS/SIGNIFICANCE: The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions

The Macro-Economic and Sectoral Impacts of HIV and AIDS in India

The adverse economic impact of HIV and AIDS occurs at three levels : the individual/household, sector, and national or macro-levels. In the early phase of the epidemic, the impacts at the sector and macro-levels are rather mild and, hence, not easily measurable or quantifiable. So far in India, given the low overall prevalence, the focus has been on the effects at the level of the individual and the household. The enlisted study, by Pradhan, Sundar and Singh (2006)1 also focuses on the impact of HIV and AIDS on affected households, which it finds to be seriously adverse, and, therefore, a matter of acute concern. At the same time, the study underplays the adverse economywide impact of AIDS. Given the current prevalence rate, the extrapolation of the household-level impact to the level of the state or the national economy does not reveal a large macro-economic impact. But, this is because the survey, on which the study is based, captures the snapshot of the economy at a given point of time, while the question of the macroeconomic impact of AIDS is essentially a dynamic one. As the HIV epidemic unfolds, its impacts are bound to be deeply compounded. These impacts cannot be assessed in their totality by a mere extrapolation of the household level impact. Furthermore, in 2005, the number of HIV-infected persons exceeds 5 million, and this number is expected to quintuple to between 20 million and 25 million by 2010. With that kind of a jump in the number of HIV cases in the next 5-10 years, there is bound to be a visible impact on the national economy. At present, little or nothing is known about the potential macro-economic impact of HIV and AIDS on the Indian economy. The rough-and-ready estimates of the macro-economic costs of AIDS that are available are of no help in guiding and accelerating the response of the Government of India to the potential threat to the economy imposed by this epidemic. A quantitative assessment of the macro-economic impact of AIDS on the Indian economy, therefore, needs to be undertaken urgently to assist the policy makers. Keeping this in mind, the study analyses the macro-economic and sectoral impacts of HIV and AIDS in India, using a fivesector computable general equilibrium (CGE) model.HIV, AIDS, macroeconomic impact of AIDS, computable general equilibrium

Impact and Cost-Effectiveness of Point-Of-Care CD4 Testing on the HIV Epidemic in South Africa.

Rapid diagnostic tools have been shown to improve linkage of patients to care. In the context of infectious diseases, assessing the impact and cost-effectiveness of such tools at the population level, accounting for both direct and indirect effects, is key to informing adoption of these tools. Point-of-care (POC) CD4 testing has been shown to be highly effective in increasing the proportion of HIV positive patients who initiate ART. We assess the impact and cost-effectiveness of introducing POC CD4 testing at the population level in South Africa in a range of care contexts, using a dynamic compartmental model of HIV transmission, calibrated to the South African HIV epidemic. We performed a meta-analysis to quantify the differences between POC and laboratory CD4 testing on the proportion linking to care following CD4 testing. Cumulative infections averted and incremental cost-effectiveness ratios (ICERs) were estimated over one and three years. We estimated that POC CD4 testing introduced in the current South African care context can prevent 1.7% (95% CI: 0.4% - 4.3%) of new HIV infections over 1 year. In that context, POC CD4 testing was cost-effective 99.8% of the time after 1 year with a median estimated ICER of US$4,468/DALY averted. In healthcare contexts with expanded HIV testing and improved retention in care, POC CD4 testing only became cost-effective after 3 years. The results were similar when, in addition, ART was offered irrespective of CD4 count, and CD4 testing was used for clinical assessment. Our findings suggest that even if ART is expanded to all HIV positive individuals and HIV testing efforts are increased in the near future, POC CD4 testing is a cost-effective tool, even within a short time horizon. Our study also illustrates the importance of evaluating the potential impact of such diagnostic technologies at the population level, so that indirect benefits and costs can be incorporated into estimations of cost-effectiveness

No. 05: The HIV and Urban Food Security Nexus

Considerable attention has been devoted to the impact of the HIV and AIDS epidemic on small farmers and the food security of the rural poor. Despite the rapid progression of the epidemic in rural areas, it remains an ever-growing challenge in the continent’s rapidly-growing cities where prevalence rates are still higher than in rural areas. This report examines the reciprocal relationship between HIV and urban food security. Much of the research and most of the policy interventions on the HIV-Urban Food Security Nexus focus on the nutritional status of individual People Living With HIV (PLHIV). Other members of households with PLHIV also experience an increase in food insecurity as household purchasing power declines and nutritional needs increase. Urban food insecurity is a complex phenomenon and nutritional research and interventions on the vicious circle of HIV and nutrition need to be reframed within a broader socio-economic perspective that encompasses all of the various aspects of urban food security

Complex Agent Networks explaining the HIV epidemic among homosexual men in Amsterdam

Simulating the evolution of the Human Immunodeficiency Virus (HIV) epidemic requires a detailed description of the population network, especially for small populations in which individuals can be represented in detail and accuracy. In this paper, we introduce the concept of a Complex Agent Network(CAN) to model the HIV epidemics by combining agent-based modelling and complex networks, in which agents represent individuals that have sexual interactions. The applicability of CANs is demonstrated by constructing and executing a detailed HIV epidemic model for men who have sex with men (MSM) in Amsterdam, including a distinction between steady and casual relationships. We focus on MSM contacts because they play an important role in HIV epidemics and have been tracked in Amsterdam for a long time. Our experiments show good correspondence between the historical data of the Amsterdam cohort and the simulation results.Comment: 21 pages, 4 figures, Mathematics and Computers in Simulation, added reference

HIV/Aids epidemic in India and predicting the impact of the national response: mathematical modeling and analysis

After two phases of AIDS control activities in India, the third phase of the National AIDS Control Programme (NACP III) was launched in July 2007. Our focus here is to predict the number of people living with HIV/AIDS (PLHA) in India so that the results can assist the NACP III planning team to determine appropriate targets to be activated during the project period (2007-2012). We have constructed a dynamical model that captures the mixing patterns between susceptibles and infectives in both low-risk and high-risk groups in the population. Our aim is to project the HIV estimates by taking into account general interventions for susceptibles and additional interventions, such as targeted interventions among high risk groups, provision of anti-retroviral therapy, and behavior change among HIV-positive individuals. Continuing the current level of interventions in NACP II, the model estimates there will be 5.06 million PLHA by the end of 2011. If 50 percent of the targets in NACP III are achieved by the end of the above period then about 0.8 million new infections will be averted in that year. The current status of the epidemic appears to be less severe compared to the trend observed in the late 1990s. The projections based on the second phase and the third phase of the NACP indicate prevention programmes which are directed towards the general and high-risk populations, and HIV-positive individuals will determine the decline or stabilization of the epidemic. Model based results are derived separately for the revised HIV estimates released in 2007. We perform a Monte Carlo procedure for sensitivity analysis of parameters and model validation. We also predict a positive role of implementation of anti-retroviral therapy treatment of 90 percent of the eligible people in the country. We present methods for obtaining disease progression parameters using convolution approaches. We also extend our models to age-structured populations