Expert Commentary

HIV/AIDS in Sub-Saharan Africa: Research roundup

2012 literature review of research studies relating to HIV/AIDS in Africa and its prevention and treatment.

Sub-Saharan Africa remains the region of the world most affected by HIV/AIDS. The World Health Organization reports that HIV/AIDS is not only the leading cause of death in the region, but also those living with AIDS in sub-Saharan Africa make up 70% of the total population of infected individuals. Additionally, the WHO notes that young women in the region contract HIV at three times the rate of their male counterparts.

The news is not all gloomy, though. The United Nations reports that between 2001 and 2009, new infections decreased in sub-Saharan Africa from 2.2 million to 1.8 million. The prevalence rate for those ages 15 to 49 similarly fell from 5.9% in 2001 to 5% in 2009.

Recent research explores a number of dimensions of the HIV/AIDS epidemic in Africa: the relationship between poverty and prevalence; the efficacy of different approaches to reducing transmissions, ranging from antiretroviral therapy to male circumcision; state responses to the epidemic; and the role of social institutions in supporting those living with HIV. The following are a representative sample of recent studies that provide different perspectives on this issue:

 

“The HIV-Poverty Thesis Re-Examined: Poverty, Wealth or Inequality as a Social Determinant of HIV Infection in Sub-Saharan Africa?”

Fox, Ashley M. Journal of Biosocial Science, July 2012. 44 : 459-480. doi: http://dx.doi.org/10.1017/S0021932011000745.

Abstract: “Although health is generally believed to improve with higher wealth, research on HIV in sub-Saharan Africa has shown otherwise. Whereas researchers and advocates have frequently advanced poverty as a social determinant that can help to explain sub-Saharan Africa’s disproportionate burden of HIV infection, recent evidence from population surveys suggests that HIV infection is higher among wealthier individuals. Furthermore, wealthier countries in Africa have experienced the fastest-growing epidemics…. The current study used micro-, meso- and macro-level data from Demographic and Health Surveys (DHS) across 170 regions within sixteen countries in sub-Saharan Africa to test the hypothesis that socioeconomic inequality, adjusted for absolute wealth, is associated with greater risk of HIV infection. These analyses reveal that inequality trumps wealth: Living in a region with greater inequality in wealth was significantly associated with increased individual risk of HIV infection, net of absolute wealth. The findings also reveal a paradox that supports a dynamic interpretation of epidemic trends: In wealthier regions/countries, individuals with less wealth were more likely to be infected with HIV, whereas in poorer regions/countries, individuals with more wealth were more likely to be infected with HIV. These findings add additional nuance to existing literature on the relationship between HIV and socioeconomic status.”

 

“HIV Treatment as Prevention: Modelling the Cost of Antiretroviral Treatment — State of the Art and Future Directions”

Meyer-Rath G.; Over, M. PLoS Medicine, 2012. 9(7): e1001247. doi: 10.1371/journal.pmed.1001247.

Abstract: “Policy discussions about the feasibility of massively scaling up antiretroviral therapy (ART) to reduce HIV transmission and incidence hinge on accurately projecting the cost of such scale-up in comparison to the benefits from reduced HIV incidence and mortality. We review the available literature on modelled estimates of the cost of providing ART to different populations around the world, and suggest alternative methods of characterising cost when modelling several decades into the future. In past economic analyses of ART provision, costs were often assumed to vary by disease stage and treatment regimen, but for treatment as prevention, in particular, most analyses assume a uniform cost per patient. This approach disregards variables that can affect unit cost, such as differences in factor prices (i.e., the prices of supplies and services) and the scale and scope of operations (i.e., the sizes and types of facilities providing ART). We discuss several of these variables, and then present a worked example of a flexible cost function used to determine the effect of scale on the cost of a proposed scale-up of treatment as prevention in South Africa. Adjusting previously estimated costs of universal testing and treatment in South Africa for diseconomies of small scale, i.e., more patients being treated in smaller facilities, adds 42% to the expected future cost of the intervention.”

 

“Creating Social Spaces to Tackle AIDS-Related Stigma: Reviewing the Role of Church Groups in Sub-Saharan Africa”

Campbell, C.; Skovdal, M.; Gibbs, A. AIDS and Behavior, 2011, Vol. 15, No. 6, 1204-1219. doi: 10.1007/s10461-010-9766-0.

Abstract: “An expanding body of literature explores the role of African church groups in facilitating or hindering the support of people living with AIDS and challenging or contributing to HIV/AIDS-related stigma. Treating church groups as social spaces in which HIV/AIDS-related stigma may potentially be challenged, we systematically review this literature, identifying five themes that highlight the complex and contradictory role of the church as a potential agent of health-enhancing social change. In many ways the church perpetuates HIV/AIDS-related stigma through (i) moralistic attitudes and (ii) its reinforcement of conservative gender ideologies. However some churches have managed to move towards action that makes a more positive contribution to HIV/AIDS management through (iii) promoting various forms of social control for HIV prevention, (iv) contributing to the care and support of the AIDS-affected and (v) providing social spaces for challenging stigmatising ideas and practices. We conclude that church groups, including church leadership, can play a key role in facilitating or hindering the creation of supportive social spaces to challenge stigma. Much work remains to be done in developing deeper understandings of the multi-layered factors that enable some churches, but not others, to respond effectively to HIV/AIDS.”

 

“Mortality Risk and Human Capital Investment: The Impact of HIV/AIDS in Sub-Saharan Africa”

Fortson, Jane G. Review of Economics and Statistics, February 2011, 93(1), 1-15.

Abstract: “Over the past several decades, the HIV/AIDS epidemic has dramatically altered patterns of morbidity and mortality in sub-Saharan Africa, with potential consequences for human capital investment and economic growth. Using data from Demographic and Health Surveys for fifteen countries in sub-Saharan Africa, I estimate the relationship between regional HIV prevalence and the change in individual human capital investment over time. Consistent with a simple model of human capital investment incorporating mortality risk, I find that areas with higher levels of HIV experienced relatively larger declines in schooling.”

 

“Concurrent Sexual Partnerships and the HIV Epidemics in Africa: Evidence to Move Forward”

Mah, Timothy L.; Halperin, Daniel T. AIDS and Behavior, 2010, Vol. 14, No. 1, 11-16. doi: 10.1007/s10461-008-9433-x.

Abstract: “The role of concurrent sexual partnerships is increasingly recognized as important for the transmission of sexually transmitted infections, particularly of heterosexual HIV transmission in Africa. Modeling and empirical evidence suggest that concurrent partnerships — compared to serial partnerships — can increase the size of an HIV epidemic, the speed at which it infects a population, and its persistence within a population. This selective review of the published and unpublished literature on concurrent partnerships examines various definitions and strategies for measuring concurrency, the prevalence of concurrency from both empirical and modeling studies, the biological plausibility of concurrency, and the social and cultural underpinnings of concurrency in southern Africa.”

 

“The Effect of Community-Based Support Services on Clinical Efficacy and Health-Related Quality of Life in HIV/AIDS Patients in Resource-Limited Settings in Sub-Saharan Africa”

Kabore, I.; Bloem, J., et al. AIDS Patient Care & STDs, September 2010, 24(9):581-94.

Abstract: “Antiretroviral therapy (ART) for HIV/AIDS in developing countries has been rapidly scaled up through directed public and private resources. Data on the efficacy of ART in developing countries are limited, as are operational research studies to determine the effect of selected nonmedical supportive care services on health outcomes in patients receiving ART. We report here on an investigation of the delivery of medical care combined with community-based supportive services for patients with HIV/AIDS in four resource-limited settings in sub-Saharan Africa, carried out between 2005 and 2007. The clinical and health-related quality of life (HRQOL) efficacy of ART combined with community support services was studied in a cohort of 377 HIV-infected patients followed for 18 months, in community-based clinics through patient interviews, clinical evaluations, and questionnaires. Patients exposed to community-based supportive services experienced a more rapid and greater overall increase in CD4 cell counts than unexposed patients. They also had higher levels of adherence, attributed primarily to exposure to home-based care services. In addition, patients receiving home-based care and/or food support services showed greater improvements in selected health-related QOL indicators. This report discusses the feasibility of effective ART in a large number of patients in resource-limited settings and the added value of concomitant community-based supportive care services.”

 

“The Role of Executive Time Horizons in State Response to AIDS in Africa”

Dionne, Kim Yi. Comparative Political Studies, January 2011, Vol. 44, No. 1, 55-77. doi: 10.1177/0010414010381074.

Abstract: “In this article the author argues that politicians’ time horizons affect the differing levels of state intervention against AIDS. Using data measuring government spending, AIDS policy, and political constraints, the author tests the presumption that the leader of a country can determine a country’s level of AIDS intervention. She looks at countries in eastern and southern Africa to explore the relationship between political institutions that constrain an executive’s time horizon (i.e., competitive elections) and the level of the state’s efforts in the fight against AIDS. Her primary hypothesis is that an executive with a shorter time horizon is less likely to create policy or devote resources to intervene against AIDS. The author finds that lengthening an executive’s time horizon increases the level of government spending on health but that executives with shorter time horizons tended to have more comprehensive AIDS policy than their counterparts with longer time horizons.”

 

“Tuberculosis and Tuberculosis/HIV/AIDS — Associated Mortality in Africa: The Urgent Need to Expand and Invest in Routine and Research Autopsies”

Zumla, Alimuddin, et al. Journal of Infectious Diseases, 2012, 205 (suppl 2): S340-S346. doi: 10.1093/infdis/jir859.

Abstract: “Frequently quoted statistics that tuberculosis and human immunodeficiency virus (HIV)/AIDS are the most important infectious causes of death in high-burden countries are based on clinical records, death certificates, and verbal autopsy studies. Causes of death ascertained through these methods are known to be grossly inaccurate. Most data from Africa on mortality and causes of death currently used by international agencies have come from verbal autopsy studies, which only provide inaccurate estimates of causes of death…. Autopsy studies could have particular relevance to direct public health interventions, such as vaccination programs or preventive therapy, and could also allow for study of background levels of subclinical tuberculosis disease, Mycobacterium tuberculosis-HIV coinfection, and other infectious and noncommunicable diseases not yet clinically manifest. Autopsies performed soon after death may represent a unique opportunity to understand the pathogenesis of M. tuberculosis and the pathogenesis of early deaths after initiation of antiretroviral therapy. The few autopsies performed so far for research purposes have yielded invaluable information and insights into tuberculosis, HIV/AIDS, and other opportunistic infections. Accurate cause-specific mortality data are essential for prioritization of governmental and donor investments into health services to reduce morbidity and mortality from deadly infectious diseases such as tuberculosis and HIV/AIDS. There is an urgent need for reviving routine and research autopsies in sub-Saharan African countries.”

 

“Predicting Trends in HIV-1 Sexual Transmission in Sub-Saharan Africa Through the Drug Resource Enhancement Against AIDS and Malnutrition Model”

Nielsen-Saines, Karin; et al. Clinical Infectious Diseases, 2012, 55 (2): 268-275. doi: 10.1093/cid/cis380.

Abstract: “The use of antiretrovirals to reduce the incidence of human immunodeficiency virus (HIV) infection has been evaluated in mathematical models as potential strategies for curtailing the epidemic. Cohort data from the Drug Resource Enhancement Against AIDS and Malnutrition (DREAM) Program was used to generate a realistic model for the HIV epidemic in sub-Saharan Africa…. Data from 26,565 patients followed up from January 2002 through July 2009 were analyzed with the model; 63% of patients were female, the median age was 35 years, and the median observation time was 25 months. In the model, a five-fold reduction in infectivity (from 1.6% to 0.3%) occurred within 3 years when triple ART was used. The annual incidence of HIV infection declined from 7% to 2% in 2 years, and the prevalence was halved, from 12% to 6%, in 11 years. Mortality in HIV-infected individuals declined by 50% in five years. A cost analysis demonstrated economic efficiency after 4 years…. Our model, based on patient data, supports the hypothesis that treatment of all infected individuals translates into a drastic reduction in incident HIV infections. A targeted implementation strategy with massive population coverage is feasible in sub-Saharan Africa.”

 

“Distribution of Antiretroviral Treatment Through Self-Forming Groups of Patients in Tete Province, Mozambique

Ford, Nathan; et al. Journal of Acquired Immune Deficiency Syndrome, 2011, 56(2):e39-44.

Abstract: “As antiretroviral treatment cohorts continue to expand, ensuring patient retention over time is an increasingly important concern. This, together with capacity and human resource constraints, have led to the consideration of out-of-clinic models for the delivery of antiretroviral therapy (ART). In 2008, Médecins Sans Frontières and the Provincial authorities launched a model of ART distribution and adherence monitoring by community groups in Tete Province, Mozambique…. Patients who were stable on ART for six months were informed about the community ART group model and invited to form groups. Group members had four key functions: facilitate monthly ART distribution to other group members in the community, provide adherence and social support, monitor outcomes, and ensure each group member undergoes a clinical consultation at least once every six months. Group members visit the health centre on a rotational basis such that each group member has contact with the health service every six months. Results: Between February 2008 and May 2010, 1,384 members were enrolled into 291 groups. Median follow up time within a group was 12.9 months (8.5-14.1). During this time 83 (6%) were transferred out, and of the 1,301 patients still in community groups, 1,269 (97.5%) were remaining in care, 30 (2%) had died, and 2 (0.2%) were lost to follow-up. Discussion: The Community ART Group model was initiated by patients to improve access, patient retention, and decongest health services. Early outcomes are highly satisfactory in terms of mortality and retention in care, lending support to such out-of-clinic approaches.”

 

“Use of Hormonal Contraceptives and Risk of HIV-1 Transmission: A Prospective Cohort Study”

Baeten, Jared M.; et al. The Lancet Infectious Diseases, January 2012, Vol. 12, Issue 1, 19-26. doi: 10.1016/S1473-3099(11)70247-X.

Abstract: “Hormonal contraceptives are used widely but their effects on HIV-1 risk are unclear. We aimed to assess the association between hormonal contraceptive use and risk of HIV-1 acquisition by women and HIV-1 transmission from HIV-1-infected women to their male partners. In this prospective study, we followed up 3,790 heterosexual HIV-1-serodiscordant couples participating in two longitudinal studies of HIV-1 incidence in seven African countries. Among injectable and oral hormonal contraceptive users and non-users, we compared rates of HIV-1 acquisition by women and HIV-1 transmission from women to men. The primary outcome measure was HIV-1 seroconversion. We used Cox proportional hazards regression and marginal structural modelling to assess the effect of contraceptive use on HIV-1 risk. Among 1,314 couples in which the HIV-1-seronegative partner was female (median follow-up 18·0 [IQR 12·6-24·2] months), rates of HIV-1 acquisition were 6.61 per 100 person-years in women who used hormonal contraception and 3.78 per 100 person-years in those who did not (adjusted hazard ratio 1.98, 95% CI 1.06-3.68, p=0.03). Among 2,476 couples in which the HIV-1-seronegative partner was male (median follow-up 18.7 [IQR 12.8-24.2] months), rates of HIV-1 transmission from women to men were 2.61 per 100 person-years in couples in which women used hormonal contraception and 1.51 per 100 person-years in couples in which women did not use hormonal contraception (adjusted hazard ratio 1.97, 95% CI 1.12-3·45, p=0·02). Marginal structural model analyses generated much the same results to the Cox proportional hazards regression. Women should be counselled about potentially increased risk of HIV-1 acquisition and transmission with hormonal contraception, especially injectable methods, and about the importance of dual protection with condoms to decrease HIV-1 risk. Non-hormonal or low-dose hormonal contraceptive methods should be considered for women with or at-risk for HIV-1.”

 

“Male Circumcision for the Prevention of Acquisition and Transmission of Sexually Transmitted Infections: The Case for Neonatal Circumcision

Tobian, Aaron A. R.; Gray, Ronald H.; Quinn, Thomas C. Archives of Pediatrics & Adolescent Medicine, 2010, 164(1):78-84. doi:10.1001/archpediatrics.2009.232.

Abstract: “The American Academy of Pediatrics (AAP) male circumcision policy states that while there are potential medical benefits of newborn male circumcision, the data are insufficient to recommend routine neonatal circumcision. Since 2005, however, 3 randomized trials have evaluated male circumcision for prevention of sexually transmitted infections. The trials found that circumcision decreases human immunodeficiency virus acquisition by 53% to 60%, herpes simplex virus type 2 acquisition by 28% to 34%, and human papillomavirus prevalence by 32% to 35% in men. Among female partners of circumcised men, bacterial vaginosis was reduced by 40%, and Trichomonas vaginalis infection was reduced by 48%. Genital ulcer disease was also reduced among males and their female partners. These findings are also supported by observational studies conducted in the United States. The AAP policy has a major impact on neonatal circumcision in the United States. This review evaluates the recent data that support revision of the AAP policy to fully reflect the evidence of long-term health benefits of male circumcision.”

 

Tags: HIV/AIDS, research roundup

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