Increases in adult life expectancy in rural South Africa: valuing the scale-up of HIV treatment

A decade of HIV-1 drug resistance in the United States: trends and characteristics in a large protease/reverse transcriptase and co-receptor tropism database from 2003 to 2012

BACKGROUND

Drug resistance testing and co-receptor tropism determination are key components of the management of antiretroviral therapy for HIV-1-infected individuals. The purpose of this study was to examine trends of HIV-1 resistance and viral evolution in the past decade by surveying a large commercial patient testing database.

METHODS

Temporal trends of drug resistance, viral fitness and co-receptor usage among samples submitted for routine phenotypic and genotypic resistance testing to protease inhibitors (PIs), nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), as well as for tropism determination were investigated.

RESULTS

Within 62,397 resistant viruses reported from 2003 to 2012, we observed a decreasing trend in the prevalence of three-class resistance (from 25% to 9%) driven by decreased resistance to PIs (43% to 21%) and NRTIs (79% to 57%), while observing a slight increase in NNRTI resistance (68% to 75%). The prevalence of CXCR4-mediated entry among tropism testing samples (n=52,945) declined over time from 47% in 2007 to 40% in 2012. A higher proportion of CXCR4-tropic viruses was observed within samples with three-class resistance (50%) compared with the group with no resistance (36%).

CONCLUSIONS

Decreased prevalence of three-class resistance and increased prevalence of one-class resistance was observed within samples reported between 2003 and 2012. The fraction of CXCR4-tropic viruses has decreased over time; however, CXCR4 usage was more prevalent among multi-class-resistant samples, which may be due to the more advanced disease stage of treatment-experienced patients. These trends have important implications for clinical practice and future drug discovery and development.

Patient satisfaction with HIV and TB treatment in a public programme in rural KwaZulu-Natal: evidence from patient-exit interviews

BACKGROUND

Patient satisfaction is a determinant of treatment uptake, adherence and retention, and an important health systems outcome. Queues, health worker-patient contact time, staff attitudes, and facility cleanliness may affect patient satisfaction. We quantified dimensions of patient satisfaction among HIV and TB patients in a rural sub-district of KwaZulu-Natal, South Africa, and identified underlying satisfaction factors that explained the data.

METHODS

We conducted patient-exit interviews with 300 HIV and 300 TB patients who were randomly selected using a two-stage cluster random sampling approach with primary sampling units (primary healthcare clinics) selected with probability-proportional-to-size sampling. We performed factor analysis to investigate underlying patient satisfaction factors. We compared the satisfaction with HIV and TB services and examined the relationships between patient satisfaction and patients' socio-demographic characteristics in multivariable regression.

RESULTS

Almost all patients (95% HIV, 97% TB) reported to be globally satisfied with the healthcare services received on the day of the interview. However, patient satisfaction with specific concrete aspects of the health services was substantially lower: 52% of HIV and 40% of TB patients agreed that some staff did not treat patients with sufficient respect (p = 0.02 for difference between the two patient groups); 65% of HIV and 40% of TB patients agreed that health worker queues were too long (p < 0.001). Based on factor analysis, we identified five factors underlying the HIV data and the TB data (availability, accommodation, acceptability and communication for HIV and TB patients; health worker preference for HIV patients only; and global satisfaction for TB patients only). The level of satisfaction did not vary significantly with patients' socio-demographic characteristics.

CONCLUSIONS

In this rural area, HIV and TB patients' evaluations of specific aspects of health services delivery revealed substantial dissatisfaction hidden in the global assessments of satisfaction. A wide range of patient satisfaction variables could be reduced to a few underlying factors that align broadly with concepts previously identified in the literature as affecting access to healthcare. Increases in health systems resources for HIV and TB, but also improvements in facility maintenance, staff attitudes and communication, are likely to substantially improve HIV and TB patients' satisfaction with the care they receive in public-sector treatment programmes in rural communities in South Africa.

Reduction in early mortality on antiretroviral therapy for adults in rural South Africa since change in CD4+ cell count eligibility criteria

OBJECTIVE

To explore the impact of expanded eligibility criteria for antiretroviral therapy (ART) on median CD4⁺ cell count at ART initiation and early mortality on ART.

METHODS

Analyses included all adults (≥16 years) initiated on first-line ART between August 2004 and July 2012. CD4⁺ cell count threshold 350 cells per microliter for all adults was implemented in August 2011. Early mortality was defined as any death within 91 days of ART initiation. Trends in baseline CD4⁺ cell count and early mortality were examined by year (August to July) of ART initiation. Competing risks analysis was used to examine early mortality.

RESULTS

A total of 19,080 adults (67.6% female) initiated ART. Median CD4⁺ cell count at ART initiation was 110-120 cells per microliter over the first 6 years, increasing marginally to 145 cells per microliter in 2010-2011 and more significantly to 199 cells per microliter in 2011-2012. Overall, there were 875 deaths within 91 days of ART initiation; early mortality rate was 19.4 per 100 person-years [95% confidence interval (CI) 18.2 to 20.7]. After adjustment for sex, age, baseline CD4⁺ cell count, and concurrent tuberculosis (TB), there was a 46% decrease in early mortality for those who initiated ART in 2011-2012 compared with the reference period 2008-2009 (subhazard ratio, 0.54; 95% CI: 0.41 to 0.71).

CONCLUSIONS

Since the expansion of eligibility criteria, there is evidence of earlier access to ART and a significant reduction in early mortality rate in this primary health care programme. These findings provide strong support for national ART policies and highlight the importance of earlier ART initiation for achieving reductions in HIV-related mortality.

Survival on antiretroviral treatment among adult HIV-infected patients in Nepal: a retrospective cohort study in Far-western region, 2006-2011

Background

Though financial and policy level efforts are made to expand antiretroviral treatment (ART) service free of cost, survival outcome of ART program has not been systematically evaluated in Nepal. This study assesses the mortality rates and determinants among adult HIV-infected patients on ART in Far-western region of Nepal.

Methods

This retrospective cohort study included 1024 (51.2% men) HIV-infected patients aged ≥15 years, who started ART between May 15^th 2006 and May 15^th 2011 in five ART sites in the Far-western region, Nepal. Follow-up time was calculated from the date of ART initiation to date of death or censoring (loss to follow-up, transferred out, or 15 November 2011). Mortality rates (per 100 person-years) were calculated. Kaplan-Meier and Cox-regression models were used to estimate survival and explore determinants of mortality.

Results

The median follow-up time was 19.1 months. The crude mortality rate was 6.3 (95% confidence interval (CI) 5.3-7.6) but more than three-times higher in first 3 months after ART initiation (21.9 (95% CI 16.6- 28.8)). About 12% (83% men) of those newly initiated on ART died during follow-up. The independent determinants of mortality were male sex (hazard ratio (HR) 4.55, 95% CI 2.43-8.51), poor baseline performance scale (bedridden <50% of the day during the past month, HR 2.05, 95% CI 1.19-3.52; bedridden >50% of the day during the past month, HR 3.41, 95% CI 1.67-6.98 compared to normal activity), one standard deviation decrease in baseline bodyweight (HR 1.04, 95% CI 1.01-1.07), and poor WHO clinical stage (stage III, HR 2.96, 95% CI 1.31-6.69; stage IV, HR 3.28, 95% CI 1.30-8.29 compared to WHO clinical stage I or II).

Conclusions

High mortality was observed within the first 3 months of ART initiation. Patients with poor baseline clinical characteristics had higher mortality, especially men. Earlier initiation of ART through expanded testing and counselling should be encouraged in HIV-infected patients.

Stigmatization of people living with HIV/AIDS by healthcare workers at a tertiary hospital in KwaZulu-Natal, South Africa: a cross-sectional descriptive study

Background

The issue of stigma is very important in the battle against HIV/AIDS in Africa since it may affect patient attendance at healthcare centres for obtaining antiretroviral (ARV) medications and regular medical check-ups. Stigmatization creates an unnecessary culture of secrecy and silence based on ignorance and fear of victimization. This study was designed to determine if there is external stigmatization of people living with HIV and AIDS (PLWHA) by health care workers (HCWs) at a tertiary hospital in KwaZulu-Natal (KZN) province, South Africa. The study investigated the impact of knowledge of HIV/AIDS by HCWs on treatment of patients, as well as the comfort level and attitude of HCWs when rendering care to PLWHA.

Methods

A descriptive cross sectional study was designed to collect data using an anonymous self-administered structured questionnaire from 334 HCWs. The study was conducted in clinical departments of a large multidisciplinary 922-bed tertiary care teaching hospital in Durban, KZN.

Results

Overall HCWs had an above average knowledge about HIV/AIDS although some gaps in knowledge were identified. Tests of statistical significance showed that there was association between level of education and knowledge of HIV/AIDs (p ≤ 0.001); occupation and knowledge of HIV/AIDS (p ≤ 0.001); and gender and knowledge of HIV/AIDS (p = 0.004). Test for comfort level was only significant for gender, with males showing more comfort and empathy when dealing with PLWHA (p = 0.003). The study also revealed that patients were sometimes tested for HIV without informed consent before surgery, due to fear of being infected, and there was some gossiping about patients' HIV status by HCWs, thereby compromising patient confidentiality. The majority of HCWs showed a willingness to report incidents of stigmatization and discrimination to higher authorities, for better monitoring and control.

Conclusions

Although knowledge, attitude and comfort level of HCWs taking care of PLWHA was above average, enforcement of existing antidiscrimination laws and continuing education in medical ethics and healthcare law, would greatly improve the performance of HCWs taking care of PLWHAs. More psychological support and counselling should be provided to HCWs, to further reduce the impact of stigmatization and discrimination against PLWHA.

Closing the gap: increases in life expectancy among treated HIV-positive individuals in the United States and Canada

BACKGROUND

Combination antiretroviral therapy (ART) has significantly increased survival among HIV-positive adults in the United States (U.S.) and Canada, but gains in life expectancy for this region have not been well characterized. We aim to estimate temporal changes in life expectancy among HIV-positive adults on ART from 2000-2007 in the U.S. and Canada.

METHODS

Participants were from the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD), aged ≥20 years and on ART. Mortality rates were calculated using participants' person-time from January 1, 2000 or ART initiation until death, loss to follow-up, or administrative censoring December 31, 2007. Life expectancy at age 20, defined as the average number of additional years that a person of a specific age will live, provided the current age-specific mortality rates remain constant, was estimated using abridged life tables.

RESULTS

The crude mortality rate was 19.8/1,000 person-years, among 22,937 individuals contributing 82,022 person-years and 1,622 deaths. Life expectancy increased from 36.1 [standard error (SE) 0.5] to 51.4 [SE 0.5] years from 2000-2002 to 2006-2007. Men and women had comparable life expectancies in all periods except the last (2006-2007). Life expectancy was lower for individuals with a history of injection drug use, non-whites, and in patients with baseline CD4 counts <350 cells/mm(3).

CONCLUSIONS

A 20-year-old HIV-positive adult on ART in the U.S. or Canada is expected to live into their early 70 s, a life expectancy approaching that of the general population. Differences by sex, race, HIV transmission risk group, and CD4 count remain.

Population-level associations between antiretroviral therapy scale-up and all-cause mortality in South Africa

Summary

Our aim was to describe the association between increasing access to antiretroviral therapy and all-cause mortality in South Africa from 2005 to 2009. We undertook a longitudinal, population-level study, using antiretroviral monitoring data reported by PEPFAR implementing partners and province-level and national all-cause mortality records from Statistics South Africa (provider of official South African government statistics) to analyse the association between antiretroviral therapy and mortality. Using mixed effects models with a random intercept for province, we estimated the contemporaneous and lagging association between antiretroviral therapy and all-cause mortality in South Africa. We also conducted subgroup analyses and estimated the number of deaths averted. For each 100 HIV-infected individuals on antiretroviral therapy reported by PEPFAR implementing partners in South African treatment programmes, there was an associated 2.9 fewer deaths that year (95% CI: 1.5, 4.2) and 6.3 fewer deaths the following year (95% CI: 4.6, 8.0). The associated decrease in mortality the year after treatment reporting was seen in both adults and children, and men and women. Treatment provided from 2005 to 2008 was associated with 28,305 deaths averted from 2006 to 2009. The scale-up of antiretroviral therapy in South Africa was associated with a significant reduction in national all-cause mortality.

The global HIV epidemic: current status and challenges

Three decades after the first reported cases of AIDS we have within our reach sufficient evidence to substantially alter the HIV epidemic at a country level regardless of mode of transmission of HIV. There are a growing number of countries demonstrating control of the epidemic. Human rights violations and/or legislation relating to sexual orientation, status of minors, injecting drug use and sex work together with stigma and discrimination remain key barriers to knowledge of HIV status and access to appropriate services. The use of anti-retrovirals prophylactically to reduce sexual and vertical transmission and systemically to treat infected infants and adults is central to the optimism in responses to the epidemic. In the current fiscal climate careful thought needs to be given to how to efficiently optimise combinations of what is available to have the biggest impact in the context of limited human and infrastructure resources.

The survival benefits of antiretroviral therapy in South Africa

BACKGROUND

We sought to quantify the survival benefits attributable to antiretroviral therapy (ART) in South Africa since 2004.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications-International model (CEPAC) to simulate 8 cohorts of human immunodeficiency virus (HIV)-infected patients initiating ART each year during 2004-2011. Model inputs included cohort-specific mean CD4(+) T-cell count at ART initiation (112-178 cells/µL), 24-week ART suppressive efficacy (78%), second-line ART availability (2.4% of ART recipients), and cohort-specific 36-month retention rate (55%-71%). CEPAC simulated survival twice for each cohort, once with and once without ART. The sum of the products of per capita survival differences and the total numbers of persons initiating ART for each cohort yielded the total survival benefits.

RESULTS

Lifetime per capita survival benefits ranged from 9.3 to 10.2 life-years across the 8 cohorts. Total estimated population lifetime survival benefit for all persons starting ART during 2004-2011 was 21.7 million life-years, of which 2.8 million life-years (12.7%) had been realized by December 2012. By 2030, benefits reached 17.9 million life-years under current policies, 21.7 million life-years with universal second-line ART, 23.3 million life-years with increased linkage to care of eligible untreated patients, and 28.0 million life-years with both linkage to care and universal second-line ART.

CONCLUSIONS

We found dramatic past and potential future survival benefits attributable to ART, justifying international support of ART rollout in South Africa.

Challenges of biobanking in South Africa to facilitate indigenous research in an environment burdened with human immunodeficiency virus, tuberculosis, and emerging noncommunicable diseases

The high burden of infectious diseases and the growing problem of noncommunicable and metabolic disease syndromes in South Africa (SA) forces a more focused research approach to facilitate cutting-edge scientific growth and public health development. Increased SA research on these diseases and syndromes and the collection of associated biospecimens has ensured a plethora of biobanks created by individuals, albeit without the foresight of prospective and collective use by other local and international researchers. As the need for access to high-quality specimens in statistically relevant numbers has increased, so has the necessity for the development of national human biobanks in SA and across the Continent. The prospects of achieving sustainable centralized biobanks are still an emerging and evolving concept, primarily and recently driven by the launch of the H3Africa consortium, which includes the development of harmonized and standardized biobanking operating procedures. This process is hindered by a myriad of complex societal considerations and ethico-legal challenges. Efforts to consolidate and standardize biological sample collections are further compromised by the lack of full appreciation by national stakeholders of the biological value inherent in these collections, and the availability of high quality human samples with well-annotated data for future scientific research and development. Inadequate or nonexistent legislative structures that specifically regulate the storage, use, dispersal, and disposal of human biological samples are common phenomena and pose further challenges. Furthermore, concerns relating to consent for unspecified future uses, as well as access to information and data protection, are all new paradigms that require further consideration and public engagement. This article reviews important fundamental issues such as governance, ethics, infrastructure, and bioinformatics that are important foundational prerequisites for the establishment and evolution of successful human biobanking in South Africa.

Do people with HIV infection have a normal life expectancy in the era of combination antiretroviral therapy?

There is evidence that the life expectancy (LE) of individuals infected with the human immunodeficiency virus (HIV) has increased since the introduction of combination antiretroviral therapy (cART). However, mortality rates in recent years in HIV-positive individuals appear to have remained higher than would be expected based on rates seen in the general population. A low CD4 count, whether due to late HIV diagnosis, late initiation of cART, or incomplete adherence to cART, remains the dominant predictor of LE, and thus the individual's disease stage at initiation of cART (or thereafter) certainly contributes to these higher mortality rates. However, individuals with HIV also tend to exhibit lifestyles and behaviors that place them at increased risk of mortality, particularly from non-AIDS causes. Thus, although mortality rates among the HIV population may indeed remain slightly higher than those seen in the general population, they may be no higher than those seen in a more appropriately matched control group. Thus, further improvements in LE may now only be possible if some of the other underlying issues (for example, modification of lifestyle or behavioral factors) are tackled.

HIV-HBV coinfection in Southern Africa and the effect of lamivudine- versus tenofovir-containing cART on HBV outcomes

BACKGROUND

This study assessed HIV-hepatitis B virus (HBV) coinfection in southern Africa in terms of prevalence, viral characteristics, occult HBV, and the effect of lamivudine- versus tenofovir-containing first-line combination antiretroviral treatment (cART) on HBV-related outcomes.

METHODS

A multicenter prospective cohort of HIV-infected adults in Zambia and South Africa who initiated cART. Outcomes by month 12 on cART were immunological recovery, hepatitis B surface antigen (HBsAg) loss, viral suppression, and drug resistance. We used descriptive statistics, logistic regression, and linear mixed models.

RESULTS

Of the 1087 participants, 92 were HBsAg seropositive, yielding a sample-weighted prevalence of 7.4% (95% confidence interval: 5.6 to 9.2), with 76% genotype HBV-A1. The estimated CD4 recovery on cART was similar between HIV monoinfection and HIV-HBV coinfection groups and between lamivudine- and tenofovir-treated participants. HBsAg loss was documented in 20% (4/20) of lamivudine-treated and 18% (3/17) of tenofovir-treated participants (P = 0.305). Viral suppression (HBV-DNA < 20 IU/mL) was achieved in 61.5% (16/26) of lamivudine-treated and 71.4% (15/21) of tenofovir-treated participants (P = 0.477). HBV pol sequencing demonstrated M204I (n = 3) and N236T (n = 1) resistance-associated mutations in 4 of 8 (50%) lamivudine-treated participants and none in tenofovir-treated participants. Occult HBV infection was present in 13.3% before cART, but by month 12, HBV-DNA was below the limit of detection (<15 IU/mL) in 90.5% (19/21) of lamivudine-treated and 100% (18/18) of tenofovir-treated participants (P = 0.179).

CONCLUSIONS

Tenofovir-containing first-line cART is preferred for HIV-HBV coinfection in Africa because of a superior resistance profile relative to lamivudine monotherapy. Extended follow-up will be needed to determine long-term complications of occult HBV coinfection. Improved access to HBsAg screening and tenofovir is needed.

The end of AIDS: HIV infection as a chronic disease

The success of antiretroviral therapy has led some people to now ask whether the end of AIDS is possible. For patients who are motivated to take therapy and who have access to lifelong treatment, AIDS-related illnesses are no longer the primary threat, but a new set of HIV-associated complications have emerged, resulting in a novel chronic disease that for many will span several decades of life. Treatment does not fully restore immune health; as a result, several inflammation-associated or immunodeficiency complications such as cardiovascular disease and cancer are increasing in importance. Cumulative toxic effects from exposure to antiretroviral drugs for decades can cause clinically-relevant metabolic disturbances and end-organ damage. Concerns are growing that the multimorbidity associated with HIV disease could affect healthy ageing and overwhelm some health-care systems, particularly those in resource-limited regions that have yet to develop a chronic care model fully. In view of the problems inherent in the treatment and care for patients with a chronic disease that might persist for several decades, a global effort to identify a cure is now underway.

Modeling the cost-effectiveness of HIV treatment: how to buy the most 'health' when resources are limited

PURPOSE OF REVIEW

To summarize recent cost-effectiveness analyses (CEAs) that evaluate optimal treatment strategies for persons living with HIV/AIDS (PLWHA).

RECENT FINDINGS

Efforts to attain universal coverage of current treatment guidelines (e.g., initiation at CD4 cell count <350 cells/μl) are generally very costeffective. Expansion of access beyond current guidelines will additionally improve clinical outcomes and aversion of new HIV infections; however, cost-effectiveness is more uncertain. Increasing access to antiretroviral therapy (ART) offers greater health benefit than investing the same funds in intensive laboratory monitoring for those on ART, particularly in those settings in which universal coverage has not yet been attained. Recommended ART regimens (e.g., tenofovir) have favorable cost-effectiveness when compared with substitution of newer, more expensive agents (e.g., rilpivirine, darunavir) or substitution of older, cheaper alternatives that are more toxic (e.g., stavudine).

SUMMARY

There is increasing use of CEA to evaluate decisions regarding HIV treatment in order to buy the most 'health' with limited resources. Expansion of ART access provides substantial clinical and preventive benefit and offers favorable cost-effectiveness. Intensive laboratory monitoring may not be the highest priority in settings in which resources are constrained. Further work on the economic impact, clinical effectiveness, and feasibility of ART treatment for all (e.g., no CD4 cell initiation criteria) is needed.

Past, present and future: 30 years of HIV research

This year marks the thirtieth anniversary of the publication of the study that first reported the isolation of HIV-1. In this Timeline article, we provide a historical perspective of some of the major milestones in HIV science, highlighting how translational research has affected treatment and prevention of HIV. Finally, we discuss some of the current research directions and the scientific challenges ahead, in particular in the search for a cure for HIV.

Elimination of HIV in South Africa through expanded access to antiretroviral therapy: a model comparison study

BACKGROUND

Expanded access to antiretroviral therapy (ART) using universal test and treat (UTT) has been suggested as a strategy to eliminate HIV in South Africa within 7 y based on an influential mathematical modeling study. However, the underlying deterministic model was criticized widely, and other modeling studies did not always confirm the study's finding. The objective of our study is to better understand the implications of different model structures and assumptions, so as to arrive at the best possible predictions of the long-term impact of UTT and the possibility of elimination of HIV.

METHODS AND FINDINGS

We developed nine structurally different mathematical models of the South African HIV epidemic in a stepwise approach of increasing complexity and realism. The simplest model resembles the initial deterministic model, while the most comprehensive model is the stochastic microsimulation model STDSIM, which includes sexual networks and HIV stages with different degrees of infectiousness. We defined UTT as annual screening and immediate ART for all HIV-infected adults, starting at 13% in January 2012 and scaled up to 90% coverage by January 2019. All models predict elimination, yet those that capture more processes underlying the HIV transmission dynamics predict elimination at a later point in time, after 20 to 25 y. Importantly, the most comprehensive model predicts that the current strategy of ART at CD4 count ≤350 cells/µl will also lead to elimination, albeit 10 y later compared to UTT. Still, UTT remains cost-effective, as many additional life-years would be saved. The study's major limitations are that elimination was defined as incidence below 1/1,000 person-years rather than 0% prevalence, and drug resistance was not modeled.

CONCLUSIONS

Our results confirm previous predictions that the HIV epidemic in South Africa can be eliminated through universal testing and immediate treatment at 90% coverage. However, more realistic models show that elimination is likely to occur at a much later point in time than the initial model suggested. Also, UTT is a cost-effective intervention, but less cost-effective than previously predicted because the current South African ART treatment policy alone could already drive HIV into elimination. Please see later in the article for the Editors' Summary.

Modelling HIV incidence and survival from age-specific seroprevalence after antiretroviral treatment scale-up in rural South Africa

OBJECTIVE

Our study uses sex-specific and age-specific HIV prevalence data from an ongoing population-based demographic and HIV survey to infer HIV incidence and survival in rural KwaZulu-Natal between 2003 and 2011, a period when antiretroviral treatment (ART) was rolled out on a large scale.

DESIGN

Catalytic mathematical model for estimating HIV incidence and differential survival in HIV-infected persons on multiple rounds of HIV seroprevalence.

METHODS

We evaluate trends of HIV incidence and survival by estimating parameters separately for women and men aged 15-49 years during three calendar periods (2003-2005, 2006-2008, 2009-2011) reflecting increasing ART coverage. We compare model-based estimates of HIV incidence with observed cohort-based estimates from the longitudinal HIV surveillance.

RESULTS

Median survival after HIV infection increased significantly between 2003-2005 and 2009-2011 from 10.0 [95% confidence interval (CI) 8.8-11.2] to 14.2 (95% CI 12.6-15.8) years in women (P < 0.001) and from 10.0 (95% CI 9.2-10.8) to 14.0 (95% CI 10.6-17.4) years in men (P = 0.02). Our model suggests no statistically significant reduction of HIV incidence in the age-group 15-49 years in 2009-2011 compared with 2003-2005. Age-specific and sex-specific model-based HIV incidence estimates were in good agreement with observed cohort-based estimates from the ongoing HIV surveillance.

CONCLUSION

Our catalytic modelling approach using cross-sectional age-specific HIV prevalence data could be useful to monitor trends of HIV incidence and survival in other African settings with a high ART coverage.

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

OBJECTIVES

To investigate HIV prevalence trends in a rural South African community after the scale-up of antiretroviral treatment (ART) in 2004.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

High-levels of acquired drug resistance in adult patients failing first-line antiretroviral therapy in a rural HIV treatment programme in KwaZulu-Natal, South Africa

Objective

To determine the frequency and patterns of acquired antiretroviral drug resistance in a rural primary health care programme in South Africa.

Design

Cross-sectional study nested within HIV treatment programme.

Methods

Adult (≥18 years) HIV-infected individuals initially treated with a first-line stavudine- or zidovudine-based antiretroviral therapy (ART) regimen and with evidence of virological failure (one viral load >1000 copies/ml) were enrolled from 17 rural primary health care clinics. Genotypic resistance testing was performed using the in-house SATuRN/Life Technologies system. Sequences were analysed and genotypic susceptibility scores (GSS) for standard second-line regimens were calculated using the Stanford HIVDB 6.0.5 algorithms.

Results

A total of 222 adults were successfully genotyped for HIV drug resistance between December 2010 and March 2012. The most common regimens at time of genotype were stavudine, lamivudine and efavirenz (51%); and stavudine, lamivudine and nevirapine (24%). Median duration of ART was 42 months (interquartile range (IQR) 32–53) and median duration of antiretroviral failure was 27 months (IQR 17–40). One hundred and ninety one (86%) had at least one drug resistance mutation. For 34 individuals (15%), the GSS for the standard second-line regimen was <2, suggesting a significantly compromised regimen. In univariate analysis, individuals with a prior nucleoside reverse-transcriptase inhibitor (NRTI) substitution were more likely to have a GSS <2 than those on the same NRTIs throughout (odds ratio (OR) 5.70, 95% confidence interval (CI) 2.60–12.49).

Conclusions

There are high levels of drug resistance in adults with failure of first-line antiretroviral therapy in this rural primary health care programme. Standard second-line regimens could potentially have had reduced efficacy in about one in seven adults involved.

Can combination prevention strategies reduce HIV transmission in generalized epidemic settings in Africa? The HPTN 071 (PopART) study plan in South Africa and Zambia

The HIV Prevention Trials Network (HPTN) is conducting the HPTN 071 (PopART) study in 21 communities in Zambia and South Africa with support from a consortium of funders. HPTN 071 (PopART) is a community-randomized trial of a combination prevention strategy to reduce HIV incidence in the context of the generalized epidemic of southern Africa. The full PopART intervention strategy is anchored in home-based HIV testing and facilitated linkage of HIV-infected persons to care through community health workers and universal antiretroviral therapy for seropositive persons regardless of CD4+ cell count or HIV viral load. To further reduce the risk of HIV acquisition among uninfected individuals, the study aims to expand voluntary medical male circumcision, diagnosis and treatment of sexually transmitted infections, behavioral counseling, and condom distribution. The full PopART intervention strategy also incorporates promotion of other interventions designed to reduce HIV and tuberculosis transmission, including optimization of the prevention of mother-to-child HIV transmission and enhanced individual and public health tuberculosis services. Success for the PopART strategy depends on the ability to increase coverage for the study interventions whose uptake is a necessary antecedent to a prevention effect. Processes will be measured to assess the degree of penetration of the interventions into the communities. A randomly sampled population cohort from each community will be used to measure the impact of the PopART strategy on HIV incidence over 3 years. We describe the strategy being tested and progress to date in the HPTN 071 (PopART) study.

A side door into care cascade for HIV-infected patients?

HIV Prevention Trials Network studies are testing a number of new technologies for preventing HIV infections and reducing AIDS morbidity and mortality, but strengthening existing antiretroviral therapy (ART) programs may be among the most promising ways to generate greater health benefits using available resources. A cascade to care for HIV-positive patients has been described-HIV testing, retention in pre-ART care, treatment initiation, and sustained suppression on ART-and it has been noted that many patients are lost at each stage. We constructed a detailed representation by combining data from different sources about each stage. We found that, although currently available data were not sufficient to specify several key aspects, the traditional model of the cascade could not fully reconcile trends in HIV testing, linkage to care, retention in pre-ART care, and retention on ART with the large numbers of persons on ART and the large percentage of patients initiating treatment at late stages of infection. We hypothesize that supplementing the traditional linear cascade model with patient health-seeking behaviors that allow patients who are not in pre-ART care to be initiated on ART, is essential to fully characterizing the current functioning of ART programs. We have termed this additional channel to ART as the "side door." Understanding the relative roles of the different channels to care will be important to intervening effectively to improve the cascade to care, and we propose several new types of data that should be collected. With these insights, it may be possible to considerably strengthen the impact of ART programs.

Towards universal voluntary HIV testing and counselling: a systematic review and meta-analysis of community-based approaches

BACKGROUND

Effective national and global HIV responses require a significant expansion of HIV testing and counselling (HTC) to expand access to prevention and care. Facility-based HTC, while essential, is unlikely to meet national and global targets on its own. This article systematically reviews the evidence for community-based HTC.

METHODS AND FINDINGS

PubMed was searched on 4 March 2013, clinical trial registries were searched on 3 September 2012, and Embase and the World Health Organization Global Index Medicus were searched on 10 April 2012 for studies including community-based HTC (i.e., HTC outside of health facilities). Randomised controlled trials, and observational studies were eligible if they included a community-based testing approach and reported one or more of the following outcomes: uptake, proportion receiving their first HIV test, CD4 value at diagnosis, linkage to care, HIV positivity rate, HTC coverage, HIV incidence, or cost per person tested (outcomes are defined fully in the text). The following community-based HTC approaches were reviewed: (1) door-to-door testing (systematically offering HTC to homes in a catchment area), (2) mobile testing for the general population (offering HTC via a mobile HTC service), (3) index testing (offering HTC to household members of people with HIV and persons who may have been exposed to HIV), (4) mobile testing for men who have sex with men, (5) mobile testing for people who inject drugs, (6) mobile testing for female sex workers, (7) mobile testing for adolescents, (8) self-testing, (9) workplace HTC, (10) church-based HTC, and (11) school-based HTC. The Newcastle-Ottawa Quality Assessment Scale and the Cochrane Collaboration's "risk of bias" tool were used to assess the risk of bias in studies with a comparator arm included in pooled estimates. 117 studies, including 864,651 participants completing HTC, met the inclusion criteria. The percentage of people offered community-based HTC who accepted HTC was as follows: index testing, 88% of 12,052 participants; self-testing, 87% of 1,839 participants; mobile testing, 87% of 79,475 participants; door-to-door testing, 80% of 555,267 participants; workplace testing, 67% of 62,406 participants; and school-based testing, 62% of 2,593 participants. Mobile HTC uptake among key populations (men who have sex with men, people who inject drugs, female sex workers, and adolescents) ranged from 9% to 100% (among 41,110 participants across studies), with heterogeneity related to how testing was offered. Community-based approaches increased HTC uptake (relative risk [RR] 10.65, 95% confidence interval [CI] 6.27-18.08), the proportion of first-time testers (RR 1.23, 95% CI 1.06-1.42), and the proportion of participants with CD4 counts above 350 cells/µl (RR 1.42, 95% CI 1.16-1.74), and obtained a lower positivity rate (RR 0.59, 95% CI 0.37-0.96), relative to facility-based approaches. 80% (95% CI 75%-85%) of 5,832 community-based HTC participants obtained a CD4 measurement following HIV diagnosis, and 73% (95% CI 61%-85%) of 527 community-based HTC participants initiated antiretroviral therapy following a CD4 measurement indicating eligibility. The data on linking participants without HIV to prevention services were limited. In low- and middle-income countries, the cost per person tested ranged from US$2-US$126. At the population level, community-based HTC increased HTC coverage (RR 7.07, 95% CI 3.52-14.22) and reduced HIV incidence (RR 0.86, 95% CI 0.73-1.02), although the incidence reduction lacked statistical significance. No studies reported any harm arising as a result of having been tested.

CONCLUSIONS

Community-based HTC achieved high rates of HTC uptake, reached people with high CD4 counts, and linked people to care. It also obtained a lower HIV positivity rate relative to facility-based approaches. Further research is needed to further improve acceptability of community-based HTC for key populations. HIV programmes should offer community-based HTC linked to prevention and care, in addition to facility-based HTC, to support increased access to HIV prevention, care, and treatment.

REVIEW REGISTRATION

International Prospective Register of Systematic Reviews CRD42012002554 Please see later in the article for the Editors' Summary.

Evolving uses of oral reverse transcriptase inhibitors in the HIV-1 epidemic: from treatment to prevention

The HIV epidemic continues unabated, with no highly effective vaccine and no cure. Each new infection has significant economic, social and human costs and prevention efforts are now as great a priority as global antiretroviral therapy (ART) scale up. Reverse transcriptase inhibitors, the first licensed class of ART, have been at the forefront of treatment and prevention of mother to child transmission over the past two decades. Now, their use in adult prevention is being extensively investigated. We describe two approaches: treatment as prevention (TasP) - the use of combination ART (2NRTI and 1NNRTI) following HIV diagnosis to limit transmission and pre-exposure prophylaxis (PrEP) –the use of single or dual oral agents prior to sexual exposure. Prevention of mother-to-child transmission using NRTI has been highly successful, though does not involve sustained use of NRTI to limit transmission. Despite theoretical and preliminary support for TasP and PrEP, data thus far indicate that adherence, retention in care and late diagnosis are the major barriers to their successful, sustained implementation. Future advances in drug technologies will be needed to overcome the issue of drug adherence, through development of drugs that involve both less frequent dosing as well as reduced toxicity, possibly through specific targeting of infected cells.

Lessons to be Learned from Natural Control of HIV - Future Directions, Therapeutic, and Preventive Implications

Accumulating data generated from persons who naturally control HIV without the need for antiretroviral treatment has led to significant insights into the possible mechanisms of durable control of AIDS virus infection. At the center of this control is the HIV-specific CD8 T cell response, and the basis for this CD8-mediated control is gradually being revealed. Genome wide association studies coupled with HLA sequence data implicate the nature of the HLA-viral peptide interaction as the major genetic factor modulating durable control of HIV, but host genetic factors account for only around 20% of the variability in control. Other factors including specific functional characteristics of the TCR clonotypes generated in vivo, targeting of vulnerable regions of the virus that lead to fitness impairing mutations, immune exhaustion, and host restriction factors that limit HIV replication all have been shown to additionally contribute to control. Moreover, emerging data indicate that the CD8⁺ T cell response may be critical for attempts to purge virus infected cells following activation of the latent reservoir, and thus lessons learned from elite controllers (ECs) are likely to impact the eradication agenda. On-going efforts are also needed to understand and address the role of immune activation in disease progression, as it becomes increasingly clear that durable immune control in ECs comes at a cost. Taken together, the research achievements in the attempt to unlock the mechanisms behind natural control of HIV will continue to be an important source of insights and ideas in the continuous search after an effective HIV vaccine, and for the attempts to achieve a sterilizing or functional cure in HIV positive patients with progressive infection.

Disengagement from care in a decentralised primary health care antiretroviral treatment programme: cohort study in rural South Africa

ObjectiveTo determine rates of, and factors associated with, disengagement from care in a decentralised antiretroviral programme.

MethodsAdults (≥16 years) who initiated antiretroviral therapy (ART) in the Hlabisa HIV Treatment and Care Programme August 2004–March 2011 were included. Disengagement from care was defined as no clinic visit for 180 days, after adjustment for mortality. Cumulative incidence functions for disengagement from care, stratified by year of ART initiation, were obtained; competing-risks regression was used to explore factors associated with disengagement from care.

ResultsA total of 4,674 individuals (median age 34 years, 29% male) contributed 13 610 person-years of follow-up. After adjustment for mortality, incidence of disengagement from care was 3.4 per 100 person-years (95% confidence interval (CI) 3.1–3.8). Estimated retention at 5 years was 61%. The risk of disengagement from care increased with each calendar year of ART initiation (P for trend <0.001). There was a strong association between disengagement from care and higher baseline CD4+ cell count (subhazard ratio (SHR) 1.94 (P < 0.001) and 2.35 (P < 0.001) for CD4+ cell count 150–200 cells/μl and >200 cells/μl respectively, compared with CD4 count <50 cells/μl). Of those disengaged from care with known outcomes, the majority (206/303, 68.0%) remained resident within the local community.

ConclusionsIncreasing disengagement from care threatens to limit the population impact of expanded antiretroviral coverage. The influence of both individual and programmatic factors suggests that alternative service delivery strategies will be required to achieve high rates of long-term retention.

Overview of the current state of the epidemic

At the end of 2011, about half of the 34.0 million [31.4-35.9 million] people living with HIV infection knew their HIV status. With large regional variations, an estimated 0.8% of all adults aged 15 to 49 years have HIV infection and HIV subtype diversity is increasing. Although HIV incidence has declined in 39 countries, it is stable or increasing in others. HIV prevalence continues to rise as antiretroviral treatment scale-up results in fewer HIV-related deaths while new infections continue to occur. Increased treatment uptake is likely reducing HIV transmission in countries with large mortality declines. Key populations, including sex workers, men who have sex with men, transgender people, people who inject drugs and young women in high prevalence settings require effective prevention programs urgently. Correcting mismatches in resource allocation and reducing community viral load will accelerate incidence declines and affect future epidemic trends, if concerted action is taken now.

High coverage of ART associated with decline in risk of HIV acquisition in rural KwaZulu-Natal, South Africa

The landmark HIV Prevention Trials Network (HPTN) 052 trial in HIV-discordant couples demonstrated unequivocally that treatment with antiretroviral therapy (ART) substantially lowers the probability of HIV transmission to the HIV-uninfected partner. However, it has been vigorously debated whether substantial population-level reductions in the rate of new HIV infections could be achieved in "real-world" sub-Saharan African settings where stable, cohabiting couples are often not the norm and where considerable operational challenges exist to the successful and sustainable delivery of treatment and care to large numbers of patients. We used data from one of Africa's largest population-based prospective cohort studies (in rural KwaZulu-Natal, South Africa) to follow up a total of 16,667 individuals who were HIV-uninfected at baseline, observing individual HIV seroconversions over the period 2004 to 2011. Holding other key HIV risk factors constant, individual HIV acquisition risk declined significantly with increasing ART coverage in the surrounding local community. For example, an HIV-uninfected individual living in a community with high ART coverage (30 to 40% of all HIV-infected individuals on ART) was 38% less likely to acquire HIV than someone living in a community where ART coverage was low (<10% of all HIV-infected individuals on ART).

[Anti-HIV drugs]

Anti-HIV drugs are fall into the following 5 categories: nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), integrase strand transfer inhibitors (INSTIs), and C-C chemokine receptor type 5 (CCR5) inhibitors. An appropriate combination of anti-HIV drugs, which is called ART (anti-retroviral therapy), can suppress HIV replication for prolonged periods. Since many anti-HIV drugs with relatively few side effects as well as high-potency have been developed recently, early initiation of ART is recommended regardless of the patients' CD4+ T-cell counts. However, ART does not lead to eradication or cure of HIV because of latent infection. Interruption of ART leads to a rapid rebound of viremia, necessitating life-long treatment. Thus, strategies to eradicate HIV from latently infected cells are urgently needed.