Adult HIV Prevalence Research Articles

Redefining the HIV epidemic in Nigeria

Background:Governments are increasingly recognizing the need to focus limited HIV resources on specific geographic areas and specific populations to have a greater impact. Nigeria, with the second largest HIV epidemic in the world, is an important example of where more localized programming has the potential to improve the efficiency of the HIV response.Methods:Using Spectrum software we modelled the Nigerian HIV epidemic using two methods: First, we created national HIV estimates using trends in urban and rural areas. Second, we created national HIV estimates using trends from each of the 37 states in Nigeria and aggregated these results. In both instances we used HIV surveillance data from antenatal clinics and household surveys and aggregated the trends to determine the national epidemic.Results:The state models showed divergent trends in the 37 states. Comparing the national results calculated from the two methods resulted in different conclusions. In the aggregated state files, adult HIV incidence in Nigeria was stable between 2005 and 2013 (change of −6%), whereas the urban and rural file suggested incidence was decreasing over the same time (change of −50%). This difference was also reflected in the HIV prevalence trends, although the two methods showed similar trends in AIDS-related mortality. The two models had similar adult HIV prevalence in 2013: 3.0% (2.0–4.5%) in the aggregated state files versus 3.2% (3.0–3.5%) in the urban/rural file.Conclusion:The state-level estimates provide insight into the variations of the HIV epidemic in each state and provide useful information for programme managers. However, the reliability of the results is highly dependent on the amount and quality of data available from each sub-national area.

Increasing Risk Awareness and Facilitating Safe Sexual Activity Among Older Adults in Senior Housing

The prevalence of HIV in older adults is rising. This increase can be attributed to inconsistent condom use, low perceived disease susceptibility, and a sexual health knowledge gap found in older adults. Yet, little to no health promotion for older adults focuses on sex education. This study sought to determine the feasibility of a group-based educational program in senior housing settings and consider the utility of a self-efficacy based group education program on knowledge of disease risk and preventive techniques among older adults living in senior housing.

Evaluation of home-based and mobile community HIV testing strategies, linkage to HIV care and treatment initiation in rural Swaziland

Swaziland has an adult HIV prevalence of 31%, yet half of HIV-positive men and a third of all HIV-positive individuals are unaware of their status. In 2012, as part of its focus on treatment as prevention, MSF introduced intensive community-based HIV testing and counselling (HTC) in rural Shiselweni. To reduce transmission rates, individuals who test HIV-positive in the community must be linked to HIV care and initiate antiretroviral therapy (ART) if eligible. In this analysis of routine programme data, we evaluated the feasibility (population reached, costs) and effectiveness (positivity rates, linkage-to-care) of two strategies of communitybased HTC, and traced clients from community HTC to ART initiation.

Adjusting the HIV prevalence for non‐respondents using mortality rates in an open cohort in northwest Tanzania

ObjectiveTo estimate HIV prevalence in adults who have not tested for HIV using age‐specific mortality rates and to adjust the overall population HIV prevalence to include both tested and untested adults.MethodsAn open cohort study was established since 1994 with demographic surveillance system (DSS) and five serological surveys conducted. Deaths from Kisesa DSS were used to estimate mortality rates and 95% confidence intervals by HIV status for 3‐ 5‐year periods (1995–1999, 2000–2004, and 2005–2009). Assuming that mortality rates in individuals who did not test for HIV are similar to those in tested individuals, and dependent on age, sex and HIV status and HIV, prevalence was estimated.ResultsIn 1995–1999, mortality rates (per 1000 person years) were 43.7 (95% CI 35.7–53.4) for HIV positive, 2.6 (95% CI 2.1–3.2) in HIV negative and 16.4 (95% CI 14.4–18.7) in untested. In 2000–2004, mortality rates were 43.3 (95% CI 36.2–51.9) in HIV positive, 3.3 (95% CI 2.8–4.0) in HIV negative and 11.9 (95% CI 10.5–13.6) in untested. In 2005–2009, mortality rates were 30.7 (95% CI 24.8–38.0) in HIV positive, 4.1 (95% CI 3.5–4.9) in HIV negative and 5.7 (95% CI 5.0–6.6) in untested residents. In the three survey periods (1995–1999, 2000–2004, 2005–2009), the adjusted period prevalences of HIV, including the untested, were 13.5%, 11.6% and 7.1%, compared with the observed prevalence in the tested of 6.0%, 6.8 and 8.0%. The estimated prevalence in the untested was 33.4%, 21.6% and 6.1% in the three survey periods.ConclusionThe simple model was able to estimate HIV prevalence where a DSS provided mortality data for untested residents.

Trends in the incidence of cancer in Kampala, Uganda 1991-2010

The Kampala cancer registry is the longest established in Africa. Trends in incidence rates for a 20-year period (1991-2010) for Kyadondo County (Kampala city and a rural hinterland) illustrate the effects of changing lifestyles in urban Africa, and the effects of the epidemic of HIV-AIDS. There has been an overall increase in the risk of cancer during the period in both sexes, with incidence rates of major cancers such as breast and prostate showing particularly marked increases (3.7% and 5.2% annually, respectively). In the 1960s cancer of the oesophagus was the most common cancer of men (and second in women), and incidence in the last 20 years has not declined. Cancer of the cervix, always the most frequent cancer of women, has shown an increase over the period (1.8% per year), although the rates appear to have declined in the last 4 years. HIV prevalence in adults in Uganda fell from a maximum in 1992 to a minimum (about 6%) in 2004, and has risen a little subsequently, while availability of antiretroviral drugs has risen sharply in recent years. Incidence of Kaposi sarcoma in men fell until about 2002, and has been relatively constant since then, while in women there has been a continuing decline since 2000. Other HIV related cancers-non-Hodgkin lymphoma of younger adults, and squamous cell carcinoma of conjunctiva-have shown major increases in incidence, although the former (NHL) has shown a small decline in incidence in the most recent 2 years.

Achieving universal access and moving towards elimination of new HIV infections in Cambodia.

IntroductionIn the mid-1990s, Cambodia faced one of the fastest growing HIV epidemics in Asia. For its achievement in reversing this trend, and achieving universal access to HIV treatment, the country received a United Nations millennium development goal award in 2010. This article reviews Cambodia’s response to HIV over the past two decades and discusses its current efforts towards elimination of new HIV infections.MethodsA literature review of published and unpublished documents, including programme data and presentations, was conducted.Results and discussionCambodia classifies its response to one of the most serious HIV epidemics in Asia into three phases. In Phase I (1991–2000), when adult HIV prevalence peaked at 1.7% and incidence exceeded 20,000 cases, a nationwide HIV prevention programme targeted brothel-based sex work. Voluntary confidential counselling and testing and home-based care were introduced, and peer support groups of people living with HIV emerged. Phase II (2001–2011) observed a steady decline in adult prevalence to 0.8% and incidence to 1600 cases by 2011, and was characterized by: expanding antiretroviral treatment (coverage reaching more than 80%) and continuum of care; linking with tuberculosis and maternal and child health services; accelerated prevention among key populations, including entertainment establishment-based sex workers, men having sex with men, transgender persons, and people who inject drugs; engagement of health workers to deliver quality services; and strengthening health service delivery systems. The third phase (2012–2020) aims to attain zero new infections by 2020 through: sharpening responses to key populations at higher risk; maximizing access to community and facility-based testing and retention in prevention and care; and accelerating the transition from vertical approaches to linked/integrated approaches.ConclusionsCambodia has tailored its prevention strategy to its own epidemic, established systematic linkages across different services and communities, and achieved nearly universal coverage of HIV services nationwide. Still, the programme must continually (re)prioritize the most effective and efficient interventions, strengthen synergies between programmes, contribute to health system strengthening, and increase domestic funding so that the gains of the previous two decades are sustained, and the goal of zero new infections is reached.

Biomedical HIV prevention research and epidemic control in Thailand: two sides of the same coin.

For a country with a moderate adult HIV prevalence of just over 1% in 2012, Thailand is widely perceived as having made some extraordinary contributions to the global management of the HIV/AIDS pandemic. It has been promoted as a model of effective HIV control and applauded for its leadership in providing access to antiretroviral treatment. Thailand has also received international recognition for its contribution to biomedical HIV prevention research, which is generally perceived as exceptional. In this paper, Thailand's global role model function as an example of effective HIV/AIDS control and high-quality biomedical HIV prevention research is re-evaluated against the background of currently available data and more recent insights. The results indicate that Thailand's initial response in raising the level of the political significance of HIV/AIDS was indeed extraordinary, which probably prevented a much larger epidemic from occurring. However, this response transpired in unusual extraconstitutional circumstances and its effectiveness declined once the country returned to political normalcy. Available data confirm the country's more than exceptional contribution to biomedical HIV prevention research. Thailand has made a huge contribution to the global management and control of the HIV/AIDS pandemic.

Corrigendum

IntroductionIn the mid‐1990s, Cambodia faced one of the fastest growing HIV epidemics in Asia. For its achievement in reversing this trend, and achieving universal access to HIV treatment, the country received a United Nations millennium development goal award in 2010. This article reviews Cambodia’s response to HIV over the past two decades and discusses its current efforts towards elimination of new HIV infections.MethodsA literature review of published and unpublished documents, including programme data and presentations, was conducted.Results and discussionCambodia classifies its response to one of the most serious HIV epidemics in Asia into three phases. In Phase I (1991–2000), when adult HIV prevalence peaked at 1.7% and incidence exceeded 20,000 cases, a nationwide HIV prevention programme targeted brothel‐based sex work. Voluntary confidential counselling and testing and home‐based care were introduced, and peer support groups of people living with HIV emerged. Phase II (2001–2011) observed a steady decline in adult prevalence to 0.8% and incidence to 1600 cases by 2011, and was characterized by: expanding antiretroviral treatment (coverage reaching more than 80%) and continuum of care; linking with tuberculosis and maternal and child health services; accelerated prevention among key populations, including entertainment establishment‐based sex workers, men having sex with men, transgender persons, and people who inject drugs; engagement of health workers to deliver quality services; and strengthening health service delivery systems. The third phase (2012–2020) aims to attain zero new infections by 2020 through: sharpening responses to key populations at higher risk; maximizing access to community and facility‐based testing and retention in prevention and care; and accelerating the transition from vertical approaches to linked/integrated approaches.ConclusionsCambodia has tailored its prevention strategy to its own epidemic, established systematic linkages across different services and communities, and achieved nearly universal coverage of HIV services nationwide. Still, the programme must continually (re)prioritize the most effective and efficient interventions, strengthen synergies between programmes, contribute to health system strengthening, and increase domestic funding so that the gains of the previous two decades are sustained, and the goal of zero new infections is reached.

A systematic review of heterosexual anal intercourse and its role in the transmission of HIV and other sexually transmitted infections in Papua New Guinea

BackgroundPapua New Guinea (PNG) has a high burden of sexually transmitted infections (STIs) and the highest adult HIV prevalence in the Pacific region. Despite this burden of disease, heterosexual anal intercourse (HAI) has rarely been considered. Given the increasing number of, and interest in, behavioural surveys in PNG and the changing nature of PNG’s HIV epidemic, it is timely to conduct a systematic review of HAI in PNG order to improve sexual health.MethodsWe performed a systematic review of HAI in PNG as reported in peer-reviewed and non-peer-reviewed publications for the period 1950–May 2012. The search strategy identified 475 publications. After screening by geographical location, topic and methodology, we identified 23 publications for full text review, following which 13 publications were included in the final review. Using data from the review, we performed a risk equation analysis to demonstrate the potential impact of HAI on HIV acquisition and incidence in PNG.ResultsThere is a paucity of well-informed behavioural research on HAI in PNG. Inconsistency in key questions on HAI made it impossible to conduct a meta-analysis. The data available on HAI shows that it is practiced in all geographical areas and among all populations. Of those who reported HAI, rates varied from as low as 8% to as high as 77% depending on the recall period and partner type. Condom use during HAI was consistently low. Our risk equation analysis indicates that even if only 20% of females engage in HAI, and only 10% of sex acts involve HAI, the total number of new HIV infections among females would be 40% greater than if vaginal intercourse only occurred.ConclusionsOur findings of indicate that HAI may be an important driver of the HIV epidemic in PNG. In order to improve the sexual health of Papua New Guineans, efforts are required to improve behavioural surveillance of HAI as well as develop national HIV/STI programing and policy to better address the risks associated with unprotected HAI.

Scaling up of family planning in low-income countries: lessons from Ethiopia

Scaling up of family planning in low-income countries: lessons from Ethiopia

Structural barriers to antiretroviral treatment: a study using population-based CD4 cell count and linked antiretroviral treatment programme data

BackgroundThe promise of an AIDS-free generation rests on treatment as prevention to reduce HIV incidence. Treatment as prevention depends critically on high antiretroviral treatment (ART) coverage. However, even under current national ART guidelines coverage remains far from universal in sub-Saharan Africa. We examined structural barriers to ART access in a community in rural South Africa, which has a very high adult HIV prevalence (28%) and incidence (approximately three new infections per 100 person-years). MethodsWe did a population-based survey of CD4 cell count among 5000 randomly selected participants in the 2010 round of a longitudinal, population-based HIV surveillance study. The study was carried out by the Africa Centre for Health and Population Studies in the Hlabisa subdistrict of KwaZula-Natal. We identified the people needing ART among the HIV-infected surveillance participants as those who were either enrolled in the local ART programme (ie, people needing and receiving ART) or people who were not enrolled in the programme but had a CD4 cell count below a certain threshold (ie, people needing ART but not yet receiving it). We applied two different CD4 cell count thresholds (≤200 and ≤350 cells per μL), leading to two different samples of people needing ART (n=376 and n=610). We then used logistic regression to explore the effect of socioeconomic factors (sex, age, education, wealth, distance to the nearest ART clinic, urban/rural residence, and migration status) on the binary outcome of ART enrolment in relation to ART need. FindingsART coverage was 72% in the 376 individuals who were either on ART or had a CD4 count of 200 cells per μL or fewer, and 45% in the 610 individuals who were either on ART or had a CD4 count of 350 cells per μL or fewer. Women who needed ART were significantly more likely to receive treatment than were men who needed it (48% vs 34%; p=0·003 for the ≤350 cells per μL threshold). The age pattern of ART coverage increased from approximately 20% at age 20 years to 60% at age 45 years, declining to 40% at age 70 years for the 350 cells per μL or fewer threshold. Controlling for other factors, among those needing ART, women were more than twice as likely to be taking ART than were men (adjusted odds ratio 2·43, 95% CI 1·36–4·33; p=0·003) and every additional km distance from the nearest clinic decreased the likelihood of ART used by approximately 20% (adjusted odds ratio 0·79, 95% CI 0·67–0·94; p=0·007). Education, wealth, and migration did not affect ART access. When we separated women into those who had not been pregnant since inception of the ART programme in 2004, and those who had been pregnant, pregnancy was a significant determinant of ART access, but explained only a small fraction (<10%) of the difference in ART access between women and men. When we used the second sample of 610 individuals, the findings remained essentially the same. InterpretationWorking towards universal coverage goals, ART programmes need to improve access for men, young and old people, and remote populations. Interventions improving geographical accessibility of ART programmes, such as subsidised transport or the opening of more ART clinics in remote areas, are likely to help to overcome important structural barriers to access. FundingThe Africa Centre for Health and Population Studies demographic and HIV surveillance is funded by the Wellcome Trust. TB and FT received financial support from the Wellcome Trust and through 1R01-HD058482-01 from the National Institute of Child Health and Human Development, National Institutes of Health.

Addressing the Growing Cancer Burden in the Wake of the AIDS Epidemic in Botswana: A Collaborative Partnership

The majority of cancer cases and nearly three-quarters of cancer deaths occur in resource-limited settings. With an adult HIV prevalence of 24.8 percent, Botswana has experienced a dramatic increase in HIV-related malignancies over the past decade. The availability of free antiretroviral treatment since 2003 has led to a major reduction in AIDS deaths; however the burden of cancer has continued to increase. The leading cancers in Botswana are cervical, non-Hodgkin lymphoma, head and neck, breast and Kaposi's sarcoma. Limited specialized oncologic services are available in two government and two private facilities, including one linear accelerator and one high dose rate brachytherapy source. With basic oncologic infrastructure in place, we sought to establish a longitudinal collaboration with the Botswana oncology community in order to improve cancer care in this nation. We focused our efforts in the following areas: the creation of a multi-disciplinary tumor board, connecting the Botswana oncology community with Massachusetts General Hospital (MGH)/Harvard-based disease site experts, on site training and capacity building in radiation oncology, and long distance learning and development. Activities have been directed through the active participation of representatives from the Botswana Ministry of Health, Botswana Harvard AIDS Institute, Gaborone Private Hospital, University of Botswana, US Embassy in Botswana, Botswana-University of Pennsylvania partnership and the MGH/Harvard oncology community. We have established the first sustainable multidisciplinary tumor board in Botswana, which has been meeting monthly since February 2012. Utilizing an internet-based platform connecting Botswana and MGH/Harvard oncology providers, case histories and pertinent radiology and pathology images are reviewed from recent challenging cases. Cases are followed by focused review of best practice by MGH/Harvard disease site experts. In addition to providing a venue for education and constructive peer review, the conference provides a regular forum for Botswana oncologists, infectious disease physicians, house officers, surgeons, and pathologists to discuss relevant health systems issues. Furthermore, the collaboration has assisted with the introduction of cervical brachytherapy in Botswana, through on site training in manual skills, treatment planning, and ongoing mentorship. A collaborative relationship in oncology care has been established between MGH/Harvard and Botswana, resulting in the introduction of new approaches to treatment and perceived improvements in patient care. The MGH/Harvard-Botswana collaboration provides a model for partnership between academic oncology centers and high burden countries with limited resources.

Dramatic increase in HIV prevalence after scale-up of antiretroviral treatment

To investigate HIV prevalence trends in a rural South African community after the scale-up of antiretroviral treatment (ART) in 2004. We estimated adult HIV prevalence (ages 15-49 years) using data from a large, longitudinal, population-based HIV surveillance in rural KwaZulu-Natal, South Africa, over the period from 2004 (the year when the public-sector ART scale-up started) to 2011. We control for selection effects due to surveillance nonparticipation using multiple imputation. We further linked the surveillance data to patient records from the local HIV treatment program to estimate ART coverage. ART coverage of all HIV-infected people in this community increased from 0% in 2004 to 31% in 2011. Over the same observation period adult HIV prevalence increased steadily from 21 to 29%. The change in overall HIV prevalence is nearly completely explained by an increase of HIV-infected people receiving ART, and it is largely driven by increases in HIV prevalence in women and men older than 24 years. The observed dramatic increase in adult HIV prevalence can most likely be explained by increased survival of HIV-infected people due to ART. Future studies should decompose HIV prevalence trends into HIV incidence and HIV-specific mortality changes to further improve the causal attribution of prevalence increases to treatment success rather than prevention failure.

Role of Fiscal Policy in Tackling the HIV/AIDS Epidemic in Southern Africa

Three countries in southern Africa have the highest adult HIV prevalence in the world: Swaziland (25.9 per cent), Botswana (24.8 per cent), and Lesotho (23.6 per cent). Fiscal policy is crucial for addressing this HIV/AIDS crisis. Utilizing a calibrated model, this paper investigates the impact of fiscal policy on reducing the HIV/AIDS incidence rates in these countries. In particular, we studied the welfare impact of different taxation and debt paths in these countries in reducing the HIV/AIDS prevalence rates. This is particularly important given the current concerns about dwindling foreign aid (especially the global AIDS fund), and the fiscal deterioration and sustainability in these countries. Our results show that, acting optimally has not only a positive societal welfare effect but also positive fiscal effects. For example, it will alleviate the debt burden by 5 per cent, 1 per cent and 13 per cent of the GDP, respectively for Botswana, Lesotho and Swaziland by the year 2020. Thus, at a time of fiscal crisis in developed countries and dwindling international HIV/AIDS resources, the future of effective and efficient HIV/AIDS intervention in Africa is clearly domestic.

Increasing Adolescent HIV Prevalence in Eastern Zimbabwe – Evidence of Long-Term Survivors of Mother-to-Child Transmission?

Recent data from the Manicaland HIV/STD Prevention Project, a general-population open HIV cohort study, suggested that between 2004 and 2007 HIV prevalence amongst males aged 15–17 years in eastern Zimbabwe increased from 1.20% to 2.23%, and in females remained unchanged at 2.23% to 2.39%, while prevalence continued to decline in the rest of the adult population. We assess whether the more likely source of the increase in adolescent HIV prevalence is recent sexual HIV acquisition, or the aging of long-term survivors of perinatal HIV acquisition that occurred during the early growth of the epidemic. Using data collected between August 2006 and November 2008, we investigated associations between adolescent HIV and (1) maternal orphanhood and maternal HIV status, (2) reported sexual behaviour, and (3) reporting recurring sickness or chronic illness, suggesting infected adolescents might be in a late stage of HIV infection. HIV-infected adolescent males were more likely to be maternal orphans (RR = 2.97, p<0.001) and both HIV-infected adolescent males and females were more likely to be maternal orphans or have an HIV-infected mother (male RR = 1.83, p<0.001; female RR = 16.6, p<0.001). None of 22 HIV-infected adolescent males and only three of 23 HIV-infected females reported ever having had sex. HIV-infected adolescents were 60% more likely to report illness than HIV-infected young adults. Taken together, all three hypotheses suggest that recent increases in adolescent HIV prevalence in eastern Zimbabwe are more likely attributable to long-term survival of mother-to-child transmission rather than increases in risky sexual behaviour. HIV prevalence in adolescents and young adults cannot be used as a surrogate for recent HIV incidence, and health systems should prepare for increasing numbers of long-term infected adolescents.

HIV Testing and Epidemiology in a Hospital‐Based Surgical Cohort in Malawi

Despite the high prevalence of HIV in adults (11 %) in Malawi, testing among surgical patients is not routine. We examined the feasibility of universal opt-out HIV testing and counseling (HTC) on the surgical wards of Kamuzu Central Hospital in Lilongwe, Malawi, and sought to further delineate the role of HIV in surgical presentation and outcome. We reviewed HTC and surgical admission records from May to October 2011 and compared these data to data collected prospectively on patients admitted from November 2011 through April 2012, after universal HTC implementation. Prior to universal HTC, 270 of the 2,606 (10.4 %) surgical admissions were tested; 13 % were HIV-infected. After universal HTC implementation, HTC counselors reviewed 1,961 of the 2,488 admissions (79 %): 310 (16 %) had known status (157 seropositive, 153 seronegative) and 1,651 had unknown status (81 %). Among those with unknown status, 97 % (1,598, of 64 % of all admissions) accepted testing, of whom 9 % were found to be HIV-infected. Patients with longer lengths of stay (LOS) (mean = 11 vs. 5 days, p < 0.01) and those who underwent surgical intervention (odds ratio [OR] 2.5; confidence interval [CI] 2.0-3.1) were more likely to have a known status on discharge. HIV was more prevalence in patients with infection and genital/anal warts or ulcers and lower in trauma patients. HIV-positive patients received less surgical intervention (OR 0.69; CI 0.52-0.90), but there was no association between HIV status and length of stay or mortality. Universal opt-out HTC on the surgical wards was well accepted and increased the proportion of patients tested. High HIV prevalence in this setting merits implementation of universal HTC.

Impact of Antiretroviral Therapy on Adult HIV Prevalence in a Low-Income Rural Setting in Uganda

To estimate the contribution to HIV prevalence of lives saved due to the introduction of antiretroviral therapy (ART) in rural Uganda in 2004. Open population-based cohort study. An open general population cohort with annual demographic and HIV serostatus data is used to estimate annual HIV prevalence, HIV incidence, and mortality from 2000 to 2010. We calculated standardized mortality rates among HIV-positive adults and the expected number of deaths in the cohort if ART had not been available during 2004-2010, based on the average mortality rate in the 4 years (2000-2003) before ART introduction. During 2004-2010, the estimated prevalence increased by 29% from 6.9% to 8.9%. HIV incidence was 5.6 cases per 1000 person-years in 2004, falling to 3.9 cases per 1000 person-years in 2006, and slightly rising to 5.1 in 2010. There was an increase of 182 in the number of HIV-positive participants during that period, cumulatively 228 lives were saved due to ART. Expected lives saved due to ART accounted for an increasing proportion of the estimated HIV prevalence from 4.0% in 2004 to 29.4% in 2010. Expected lives saved due to ART largely accounted for the increased estimated HIV prevalence from 2004 to 2010. Because HIV prevalence survey results are important for planning, programming, and policy, their interpretation requires consideration of the increasing impact of ART in decreasing mortality.

Ten Year Trends in Community HIV Viral Load in Barbados: Implications for Treatment as Prevention

BackgroundTreatment as prevention is a paradigm in HIV medicine which describes the public health benefit of antiretroviral therapy (ART). It is based on research showing substantial reductions in the risk of HIV transmission in persons with optimally suppressed HIV-1 Viral Loads (VL). The present study describes ten year VL trends at the national HIV treatment unit and estimates VL suppression at a population level in Barbados, a Caribbean island with a population of 277,000, an estimated adult HIV prevalence of 1.2%, and served by a single treatment unit.MethodsThe national HIV treatment centre of the Barbados Ministry of Health has a client VL database extending back to inception of the clinic in 2002 (n = 1,462 clients, n = 17,067 VL measurements). Optimal VL suppression was defined at a threshold value of ≤200 viral copies/mL.ResultsAnalysis of VL trends showed a statistically significant improvement in VL suppression between 2002 to 2011, from 33.6% of clients achieving the 200 copies/mL threshold in 2002 to 70.3% in 2011 (P<0.001). Taking into account the proportion of clients alive and in care and on ART, the known diagnosed HIV population in Barbados, and estimates of unknown HIV infections, this translates into an estimated 26.2% VL suppression at a population level at the end of 2010.ConclusionsWe have demonstrated a significant trend towards optimal VL suppression in clients utilizing the services of the national HIV treatment program in Barbados over a 10-year period. Estimates of VL suppression at a population level are similar to reports in developed countries that applied similar methodologies and this could suggest a public health benefit of ART in minimizing the risk of sexual transmission of HIV. Continued efforts are warranted to extend HIV testing to hidden populations in Barbados and linking infected persons to care earlier in their disease.

Control of (Multi)Drug Resistance and Tuberculosis Incidence over 23 Years in the Context of a Well-Supported Tuberculosis Programme in Rural Malawi

BackgroundThe rise in tuberculosis (TB) incidence following generalized HIV epidemics can overwhelm TB control programmes in resource-limited settings, sometimes accompanied by rising rates of drug resistance. This has led to claims that DOTS-based TB control has failed in such settings. However, few studies have described the effect of a sustained and well-supported DOTS programme on TB incidence and drug resistance over a long period. We present long-term trends in incidence and drug resistance in rural Malawi.MethodsKaronga District in northern Malawi has an adult HIV prevalence of ∼10%. A research group, the Karonga Prevention Study, collaborates with the National Tuberculosis Programme to support core TB control activities. Bacteriological, demographic and clinical (including HIV status) information from all patients starting TB treatment in the District have been recorded since 1988. During that period isolates from each culture-positive TB patient were exported for drug sensitivity testing. Antiretroviral therapy (ART) has been widely available since 2005.ResultsIncidence of new smear-positive adult TB peaked at 124/100,000/year in the mid-90s, but has since fallen to 87/100,000/year. Drug sensitivity information was available for 95% (3132/3307) of all culture-positive cases. Initial resistance to isoniazid was around 6% with no evidence of an increase. Fewer than 1% of episodes involved a multi-drug resistant strain.DiscussionIn this setting with a generalised HIV epidemic and medium TB burden, a well-supported DOTS programme enhanced by routine culture and drug sensitivity testing may well have reduced TB incidence and maintained drug resistance at low levels.

Understanding the Potential Impact of a Combination HIV Prevention Intervention in a Hyper-Endemic Community

ObjectivesDespite demonstrating only partial efficacy in preventing new infections, available HIV prevention interventions could offer a powerful strategy when combined. In anticipation of combination HIV prevention programs and research studies we estimated the population-level impact of combining effective scalable interventions at high population coverage, determined the factors that influence this impact, and estimated the synergy between the components.MethodsWe used a mathematical model to investigate the effect on HIV incidence of a combination HIV prevention intervention comprised of high coverage of HIV testing and counselling, risk reduction following HIV diagnosis, male circumcision for HIV-uninfected men, and antiretroviral therapy (ART) for HIV-infected persons. The model was calibrated to data for KwaZulu-Natal, South Africa, where adult HIV prevalence is approximately 23%.ResultsCompared to current levels of HIV testing, circumcision, and ART, the combined intervention with ART initiation according to current guidelines could reduce HIV incidence by 47%, from 2.3 new infections per 100 person-years (pyar) to 1.2 per 100 pyar within 4 years and by almost 60%, to 1 per 100 pyar, after 25 years. Short-term impact is driven primarily by uptake of testing and reductions in risk behaviour following testing while long-term effects are driven by periodic HIV testing and retention in ART programs. If the combination prevention program incorporated HIV treatment upon diagnosis, incidence could be reduced by 63% after 4 years and by 76% (to about 0.5 per 100 pyar) after 15 years. The full impact of the combination interventions accrues over 10–15 years. Synergy is demonstrated between the intervention components.ConclusionHigh coverage combination of evidence-based strategies could generate substantial reductions in population HIV incidence in an African generalized HIV epidemic setting. The full impact could be underestimated by the short assessment duration of typical evaluations.