Population uptake of HIV testing, treatment, viral suppression, and male circumcision following a community-based intervention in Botswana (Ya Tsie/BCPP): a cluster-randomised trial

Impact of Hepatitis Delta Virus Infection on the Selection of Hepatitis B Surface Antigen Mutations

The interaction of multiple viruses in one host is thought to enhance the development of mutations. However, the impact of hepatitis D virus (HDV) positivity on the development of unique hepatitis B virus (HBV) mutations among people living with human immunodeficiency virus (HIV) (PLWH) remains poorly understood in African countries, including Botswana. We used HBV sequences generated from the Botswana Combination Prevention Project (BCPP), which is the largest pair-matched cluster-randomized HIV trial in Botswana. Only participants with available HBV sequences (n = 55) were included in our study ([HIV/HBV-positive (n = 50) and HIV/HBV/HDV-positive (n = 5)]. Geno2pheno was used to determine HBV genotypes, and HBV surface region sequences (all subgenotype A1) were aligned in AliView for mutational analysis, while the impact of mutations was assessed using Phyre2. Our results identified 182 common mutations between the two groups. In the HIV/HBV/HDV cohort, only three mutations (L95W, W156Q, C221Y) were classified as deleterious, with only L95W being the most frequent. In the HIV/HBV cohort, four mutations (W199R, C221A, C221S, W223G) were also classified as deleterious. Our results demonstrate the presence of unique HBV mutations among the HIV/HBV/HDV-positive cohort. Functional characterization of these mutations is recommended to determine their effect on HDV.

Virological Suppression and its Predictors Among HIV/AIDS Patients on Antiretroviral Therapy in Ethiopia: Systematic Review and Meta-analysis

Background

Achieving viral load suppression is crucial for the prevention of complications and deaths related to HIV infection. Ethiopia has embraced the worldwide 95-95-95 target, but there is no national representative information regarding virological suppression. Therefore, this review aims to determine the pooled virological suppression rate and identify the pooled effect of contributing factors of viral suppression for HIV-positive patients on antiretroviral therapy in Ethiopia.

Methods

We systematically searched websites and databases, including online repositories, to obtain primary studies. Two reviewers assessed the quality of the included articles using the Newcastle-Ottawa Scale appraisal checklist. Publication bias was checked using Egger's regression test, the heterogeneity of the studies was assessed using I2 statistics and Q statistics, and a sensitivity analysis was performed to identify any outlier results in the included studies. The Der Simonian Laird random-effects model was used to estimate the overall proportion of viral suppression, and STATA 17 statistical software was used for all types of analysis.

Results

A total of 21 eligible articles primarily conducted in Ethiopia using HIV program data were used for this quantitative synthesis. The overall pooled virological suppression rate was 71% (95% CI, 64%-77%). The pooled effects of poor adherence to ART (adjusted odds ratio [AOR], 0.33; 95% CI, 0.28-0.40), body mass index (18.5-24.9 kg/m2; AOR, 1.8; 95% CI, 1.37-2.36), disclosure (AOR, 1.41; 95% CI, 1.05-1.89), absence of opportunistic infection (AOR, 1.68; 95% CI, 1.43-1.97), and high baseline viral load count (AOR, 0.65; 95% CI, 0.52-0.81) were identified as significant predictors of viral suppression.

Conclusions

The overall pooled percentage of virological suppression was low compared with the global target of viral suppression and the Ethiopian Public Health Institute report. Poor adherence, normal body mass index, disclosure, absence of opportunistic infection, and high baseline viral load count were factors contributing to viral suppression in Ethiopia. Responsible stakeholders should maximize their efforts to achieve the global target of virological suppression by addressing significant predictors.

High prevalence of hepatitis delta virus among people with hepatitis B virus and HIV coinfection in Botswana

BACKGROUND

Approximately 15-20 million people worldwide are infected with hepatitis delta virus (HDV), which is approximately 5 % of people with chronic hepatitis B virus (HBV). Sub-Saharan Africa has high HDV prevalence, leading to worse clinical outcomes among people who are HIV/HBV/HDV tri-infected. There are limited data on HDV prevalence among people with HIV (PWH) who are HBV-infected and uninfected in Botswana. We, therefore, determined HDV prevalence among PWH in Botswana.

METHODS

This was a retrospective cross-sectional study utilizing archived plasma samples from PWH with results for HBV markers such as hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), immunoglobulin M antibody to hepatitis B core antigen (IgM anti-HBc) and hepatitis B e antigen (HBeAg). Samples were categorized according to their HBsAg status and screened for anti-HDV antibodies. Total nucleic acid was extracted from samples with a single positive anti-HDV result, and HDV ribonucleic acid (RNA) load was quantified using the Altona Diagnostic RealStar® HDV RT-PCR kit. Statistical analysis was performed using STATA version 14.0 where p-values < 0.05 were considered statistically significant.

RESULTS

The study cohort (n = 478) included both HBsAg positive (44 %) and negative (56 %) participants, with a median age of 42 [IQR; 41-43]. Anti-HDV prevalence of (15/211) [7.1 %, 95 % CI: 4.4 - 11.4] was recorded among HBsAg positive participants, all of whom were IgM anti-HBc negative, while 5/6 participants were HBeAg negative. HDV RNA load was detected in 11/12 (92 %) anti-HDV-positive participants. No HDV prevalence was recorded among participants who were HBsAg negative, therefore, the overall HDV prevalence was (15/478) [3.1 %, 95 % CI: 1.9 - 5.1]. HIV viral load suppression was statistically insignificant, irrespective of HDV status.

CONCLUSIONS

We report high HDV prevalence among HBsAg-positive PWH in Botswana. Most HDV-positive participants had active HDV infection, therefore, we recommend HDV screening in this cohort to guide their clinical care.

Estimating contact network properties by integrating multiple data sources associated with infectious diseases

To effectively mitigate the spread of communicable diseases, it is necessary to understand the interactions that enable disease transmission among individuals in a population; we refer to the set of these interactions as a contact network. The structure of the contact network can have profound effects on both the spread of infectious diseases and the effectiveness of control programs. Therefore, understanding the contact network permits more efficient use of resources. Measuring the structure of the network, however, is a challenging problem. We present a Bayesian approach to integrate multiple data sources associated with the transmission of infectious diseases to more precisely and accurately estimate important properties of the contact network. An important aspect of the approach is the use of the congruence class models for networks. We conduct simulation studies modeling pathogens resembling SARS-CoV-2 and HIV to assess the method; subsequently, we apply our approach to HIV data from the University of California San Diego Primary Infection Resource Consortium. Based on simulation studies, we demonstrate that the integration of epidemiological and viral genetic data with risk behavior survey data can lead to large decreases in mean squared error (MSE) in contact network estimates compared to estimates based strictly on risk behavior information. This decrease in MSE is present even in settings where the risk behavior surveys contain measurement error. Through these simulations, we also highlight certain settings where the approach does not improve MSE.

Prediction of Coreceptor Tropism in HIV-1 Subtype C in Botswana

It remains unknown whether the C-C motif chemokine receptor type 5 (CCR5) coreceptor is still the predominant coreceptor used by Human Immunodeficiency Virus-1 (HIV-1) in Botswana, where the HIV-1 subtype C predominates. We sought to determine HIV-1C tropism in Botswana using genotypic tools, taking into account the effect of antiretroviral treatment (ART) and virologic suppression. HIV-1 gp120 V3 loop sequences from 5602 participants were analyzed for viral tropism using three coreceptor use predicting algorithms/tools: Geno2pheno, HIV-1C Web Position-Specific Score Matrices (WebPSSM) and the 11/25 charge rule. We then compared the demographic and clinical characteristics of people living with HIV (PLWH) harboring R5- versus X4-tropic viruses using χ2 and Wilcoxon rank sum tests for categorical and continuous data analysis, respectively. The three tools congruently predicted 64% of viruses as either R5-tropic or X4-tropic. Geno2pheno and the 11/25 charge rule had the highest concordance at 89%. We observed a significant difference in ART status between participants harboring X4- versus R5-tropic viruses. X4-tropic viruses were more frequent among PLWH receiving ART (χ2 test, p = 0.03). CCR5 is the predominant coreceptor used by HIV-1C strains circulating in Botswana, underlining the strong potential for CCR5 inhibitor use, even in PLWH with drug resistance. We suggest that the tools for coreceptor prediction should be used in combination.

Universal Health Coverage for Antiretroviral Treatment: A Review

Universal health coverage is essential for the progress to end threats of the acquired immunodeficiency syndrome epidemic. The current review assesses the publication rate, strategies and barriers for antiretroviral therapy (ART) coverage, equity, quality of care, and financial protection. We searched Web of Science, PubMed, and Google Scholar. Of the available articles, 43.13% were on ART coverage, 40.28% were on financial protection, 10.43% were on quality of care, and 6.16% were on equity. A lack of ART, fear of unwanted disclosure, lack of transportation, unaffordable health care costs, long waiting time to receive care, and poverty were barriers to ART coverage. Catastrophic health care costs were higher among individuals who were living in rural settings, walked greater distances to reach health care institutions, had a lower socioeconomic status, and were immunocompromised. There were challenges to the provision of quality of care, including health care providers' inadequate salary, high workload and inadequate health workforce, inappropriate infrastructure, lack of training opportunities, unclear division of responsibility, and the presence of strict auditing. In conclusion, ART coverage was below the global average, and key populations were disproportionally less covered with ART in most countries. Huge catastrophic health expenditures were observed. UHC contexts of ART will be improved by reaching people with poor socioeconomic status, delivering appropriate services, establishing a proper health workforce and service stewardship.

Achieving the UNAIDS 90-90-90 targets: a comparative analysis of four large community randomised trials delivering universal testing and treatment to reduce HIV transmission in sub-Saharan Africa

BACKGROUND

Four large community-randomized trials examining universal testing and treatment (UTT) to reduce HIV transmission were conducted between 2012-2018 in Botswana, Kenya, Uganda, Zambia and South Africa. In 2014, the UNAIDS 90-90-90 targets were adopted as a useful metric to monitor coverage. We systematically review the approaches used by the trials to measure intervention delivery, and estimate coverage against the 90-90-90 targets. We aim to provide in-depth understanding of the background contexts and complexities that affect estimation of population-level coverage related to the 90-90-90 targets.

METHODS

Estimates were based predominantly on "process" data obtained during delivery of the interventions which included a combination of home-based and community-based services. Cascade coverage data included routine electronic health records, self-reported data, survey data, and active ascertainment of HIV viral load measurements in the field.

RESULTS

The estimated total adult populations of trial intervention communities included in this study ranged from 4,290 (TasP) to 142,250 (Zambian PopART Arm-B). The estimated total numbers of PLHIV ranged from 1,283 (TasP) to 20,541 (Zambian PopART Arm-B). By the end of intervention delivery, the first-90 target (knowledge of HIV status among all PLHIV) was met by all the trials (89.2%-94.0%). Three of the four trials also achieved the second- and third-90 targets, and viral suppression in BCPP and SEARCH exceeded the UNAIDS target of 73%, while viral suppression in the Zambian PopART Arm-A and B communities was within a small margin (~ 3%) of the target.

CONCLUSIONS

All four UTT trials aimed to implement wide-scale testing and treatment for HIV prevention at population level and showed substantial increases in testing and treatment for HIV in the intervention communities. This study has not uncovered any one estimation approach which is superior, rather that several approaches are available and researchers or policy makers seeking to measure coverage should reflect on background contexts and complexities that affect estimation of population-level coverage in their specific settings. All four trials surpassed UNAIDS targets for universal testing in their intervention communities ahead of the 2020 milestone. All but one of the trials also achieved the 90-90 targets for treatment and viral suppression. UTT is a realistic option to achieve 95-95-95 by 2030 and fast-track the end of the HIV epidemic.

HIV Incidence in Botswana Rural Communities With High Antiretroviral Treatment Coverage: Results From the Botswana Combination Prevention Project, 2013-2017

BACKGROUND AND SETTING

The Botswana Combination Prevention Project demonstrated a 30% reduction in community HIV incidence through expanded HIV testing, enhanced linkage to care, and universal antiretroviral treatment and exceeded the Joint United Nations Programme on HIV/AIDS 90-90-90 targets. We report rates and characteristics of incident HIV infections.

METHODS

The Botswana Combination Prevention Project was a community-randomized controlled trial conducted in 30 rural/periurban Botswana communities from 2013 to 2017. Home-based and mobile HIV-testing campaigns were conducted in 15 intervention communities, with 39% of participants testing at least twice. We assessed the HIV incidence rate [IR; number of new HIV infections per 100 person-years (py) at risk] among repeat testers and risk factors with a Cox proportional hazards regression model.

RESULTS

During 27,517 py, 195 (women: 79%) of 18,597 became HIV-infected (0.71/100 py). Women had a higher IR (1.01/100 py; 95% confidence interval: 0.99 to 1.02) than men (0.34/100 py; 95% confidence interval: 0.33 to 0.35). The highest IRs were among women aged 16-24 years (1.87/100 py) and men aged 25-34 years (0.56/100 py). The lowest IRs were among those aged 35-64 years (women: 0.41/100 py; men: 0.20/100 py). The hazard of incident infection was the highest among women aged 16-24 years (hazard ratio = 7.05). Sex and age were significantly associated with incidence (both P < 0.0001).

CONCLUSIONS

Despite an overall reduction in HIV incidence and approaching the United Nations Programme on HIV/AIDS 95-95-95 targets, high HIV incidence was observed in adolescent girls and young women. These findings highlight the need for additional prevention services (pre-exposure prophylaxis and DREAMS) to achieve epidemic control in this subpopulation and increased efforts with men with undiagnosed HIV.

Achieving the 95 95 95 targets for all: A pathway to ending AIDS

In December 2020, UNAIDS released a new set of ambitious targets calling for 95% of all people living with HIV to know their HIV status, 95% of all people with diagnosed HIV infection to receive sustained antiretroviral therapy, and 95% of all people receiving antiretroviral therapy to have viral suppression by 2025. Adopted by United Nations Member states in June 2021 as part of the new Political Declaration on HIV and AIDS, these targets, combined with ambitious primary prevention targets and focused attention to supporting enablers, aim to bridge inequalities in treatment coverage and outcomes and accelerate HIV incidence reductions by focusing on progress in all sub-populations, age groups and geographic settings. Here we summarise the evidence and decisions underpinning the new global targets.

Health Impact and Cost-Effectiveness of HIV Testing, Linkage, and Early Antiretroviral Treatment in the Botswana Combination Prevention Project

BACKGROUND

The Botswana Combination Prevention Project tested the impact of combination prevention (CP) on HIV incidence in a community-randomized trial. Each trial arm had ∼55,000 people, 26% HIV prevalence, and 72% baseline ART coverage. Results showed intensive testing and linkage campaigns, expanded antiretroviral treatment (ART), and voluntary male medical circumcision referrals increased coverage and decreased incidence over ∼29 months of follow-up. We projected lifetime clinical impact and cost-effectiveness of CP in this population.

SETTING

Rural and periurban communities in Botswana.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications model to estimate lifetime health impact and cost of (1) earlier ART initiation and (2) averting an HIV infection, which we applied to incremental ART initiations and averted infections calculated from trial data. We determined the incremental cost-effectiveness ratio [US$/quality-adjusted life-years (QALY)] for CP vs. standard of care.

RESULTS

In CP, 1418 additional people with HIV initiated ART and an additional 304 infections were averted. For each additional person started on ART, life expectancy increased 0.90 QALYs and care costs increased by $869. For each infection averted, life expectancy increased 2.43 QALYs with $9200 in care costs saved. With CP, an additional $1.7 million were spent on prevention and $1.2 million on earlier treatment. These costs were mostly offset by decreased care costs from averted infections, resulting in an incremental cost-effectiveness ratio of $79 per QALY.

CONCLUSIONS

Enhanced HIV testing, linkage, and early ART initiation improve life expectancy, reduce transmission, and can be cost-effective or cost-saving in settings like Botswana.

Male circumcision uptake during the Botswana Combination Prevention Project

INTRODUCTION

Voluntary medical male circumcision (VMMC) uptake has been slow in some countries, including Botswana. To inform demand creation efforts, we examined sociodemographic characteristics and referral procedures associated with VMMC uptake in the Botswana Combination Prevention Project (BCPP) and examined the effectiveness of referral of men to MC services from HIV testing venues.

DESIGN

BCPP was a community-randomized trial evaluating the impact of a combination HIV prevention package which included VMMC on community HIV incidence. We conducted a sub-analysis of VMMC uptake in intervention communities.

METHODS

During the initial VMMC campaign in 15 intervention communities, baseline male circumcision (MC) status was assessed among men eligible for HIV testing. Uncircumcised male community residents aged 16-49 years with negative/unknown HIV status were mobilized and linked to study VMMC services. Outcomes included MC baseline status and uptake through study services. Univariate and multivariate logistic regressions were performed to identify factors associated with MC uptake.

RESULTS

Of 12,864 men eligible for testing, 50% (n = 6,448) were already circumcised. Among the uncircumcised men (n = 6,416), 10% (n = 635) underwent MC. Of the 5,071 men identified as eligible for MC through HIV testing services, 78% declined referral and less than 1% of those were circumcised. Of those accepting referral (n = 1,107), 16% were circumcised. Younger (16-24 years) (aOR: 1.51; 95%CI:1.22,1.85), unemployed men (aOR:1.34; 95%CI: 1.06,1.69), and those undergoing HIV testing at mobile venues (aOR: 1.88; 95%CI: 1.53,2.31) were more likely to get circumcised. Fear of pain was the most prevalent (27%) reason given for not being circumcised.

CONCLUSION

Younger, unemployed men seeking HIV testing at mobile sites in Botswana were more likely to get VMMC. Addressing unique barriers for employed and older men may be necessary. Given the simplicity of VMMC as an intervention, the HIV testing programs offer a platform for identifying uncircumcised men and offering information and encouragement to access services.

HIV-1 drug resistance mutations among individuals with low-level viraemia while taking combination ART in Botswana

OBJECTIVES

To assess whether a single instance of low-level viraemia (LLV) is associated with the presence of drug resistance mutations (DRMs) and predicts subsequent virological failure (VF) in adults receiving ART in 30 communities participating in the Botswana Combination Prevention Project.

METHODS

A total of 6078 HIV-1 C pol sequences were generated and analysed using the Stanford HIV drug resistance database. LLV was defined as plasma VL = 51-999 copies/mL and VF was defined as plasma VL ≥ 1000 copies/mL.

RESULTS

Among 6078 people with HIV (PWH), 4443 (73%) were on ART for at least 6 months. Of the 332 persons on ART with VL > 50 copies/mL, 175 (4%) had VL ≥ 1000 copies/mL and 157 (4%) had LLV at baseline. The prevalence of any DRM was 57 (36%) and 78 (45%) in persons with LLV and VL ≥ 1000 copies/mL, respectively. Major DRMs were found in 31 (20%) with LLV and 53 (30%) with VL ≥ 1000 copies/mL (P = 0.04). Among the 135 PWH with at least one DRM, 17% had NRTI-, 35% NNRTI-, 6% PI- and 3% INSTI-associated mutations. Among the 3596 participants who were followed up, 1709 (48%) were on ART for ≥6 months at entry and had at least one subsequent VL measurement (median 29 months), 43 (3%) of whom had LLV. The OR of experiencing VF in persons with LLV at entry was 36-fold higher than in the virally suppressed group.

CONCLUSIONS

A single LLV measurement while on ART strongly predicted the risk of future VF, suggesting the use of VL > 50 copies/mL as an indication for more intensive adherence support with more frequent VL monitoring.

Men missing from the HIV care continuum in sub-Saharan Africa: a meta-analysis and meta-synthesis

INTRODUCTION

Men are missing along the HIV care continuum. However, the estimated proportions of men in sub-Saharan Africa meeting the UNAIDS 95-95-95 goals vary substantially between studies. We sought to estimate proportions of men meeting each of the 95-95-95 goals across studies in sub-Saharan Africa, describe heterogeneity, and summarize qualitative evidence on factors influencing care engagement.

METHODS

We systematically searched PubMed and Embase for peer-reviewed articles published between 1 January 2014 and 16 October 2020. We included studies involving men ≥15 years old, with data from 2009 onward, reporting on at least one 95-95-95 goal in sub-Saharan Africa. We estimated pooled proportions of men meeting these goals using DerSimonion-Laird random effects models, stratifying by study population (e.g. studies focusing exclusively on men who have sex with men vs. studies that did not), facility setting (healthcare vs. community site), region (eastern/southern Africa vs. western/central Africa), outcome measurement (e.g. threshold for viral load suppression), median year of data collection (before vs. during or after 2017) and quality criteria. Data from qualitative studies exploring barriers to men's HIV care engagement were summarized using meta-synthesis.

RESULTS AND DISCUSSION

We screened 14,896 studies and included 129 studies in the meta-analysis, compiling data over the data collection period. Forty-seven studies reported data on knowledge of serostatus, 43 studies reported on antiretroviral therapy use and 74 studies reported on viral suppression. Approximately half of men with HIV reported not knowing their status (0.49 [95% CI, 0.41-0.58; range, 0.09-0.97]) or not being on treatment (0.58 [95% CI, 0.51-0.65; range, 0.07-0.97]), while over three-quarters of men achieved viral suppression on treatment (0.79 [95% CI, 0.77-0.81; range, 0.39-0.97]. Heterogeneity was high, with variation in estimates across study populations, settings and outcomes. The meta-synthesis of 40 studies identified three primary domains in which men described risks associated with engagement in HIV care: perceived social norms, health system challenges and poverty.

CONCLUSIONS

Psychosocial and systems-level interventions that change men's perceptions of social norms, improve trust in and accessibility of the health system, and address costs of accessing care are needed to better engage men, especially in HIV testing and treatment.

To achieve 95-95-95 targets we must reach men and youth: High level of knowledge of HIV status, ART coverage, and viral suppression in the Botswana Combination Prevention Project through universal test and treat approach

BACKGROUND

Increasing HIV treatment coverage is crucial to reducing population-level HIV incidence.

METHODS

The Botswana Combination Prevention Project (BCPP) was a community randomized trial examining the impact of multiple prevention interventions on population-level HIV incidence and was conducted from October 2013 through June 2017. Home and mobile campaigns offered HIV testing to all individuals ≥ age 16. All identified HIV-positive persons who were not on antiretroviral therapy (ART) were referred to treatment and tracked to determine linkage to care, ART status, retention in treatment, and viral suppression.

RESULTS

Of an estimated total of 14,270 people living with HIV (PLHIV) residing in the 15 intervention communities, BCPP identified 13,328 HIV-positive persons (93%). At study start, 10,703 (80%) of estimated PLHIV knew their status; 2,625 (20%) learned their status during BCPP, a 25% increase with the greatest increases occurring among men (37%) and youth (77%). At study start, 9,258 (65%) of estimated PLHIV were on ART. An additional 3,001 persons started ART through the study. By study end, 12,259 had initiated and were retained on ART, increasing coverage to 93%. A greater increase in ART coverage was achieved among men (40%) compared to women (29%). Of the 11,954 persons who had viral load (VL) test results, 11,687 (98%) were virally suppressed (HIV-1 RNA ≤400 copies/mL). Overall, 82% had documented VL suppression by study end.

CONCLUSIONS

Knowledge of HIV-positive status and ART coverage increased towards 95-95 targets with universal testing, linkage interventions, and ART. The increases in HIV testing and ART use among men and youth were essential to reaching these targets.

CLINICAL TRIAL NUMBER

NCT01965470.

AIDS and COVID: A tale of two pandemics and the role of statisticians

The world has experienced three global pandemics over the last half-century: HIV/AIDS, H1N1, and COVID-19. HIV/AIDS and COVID-19 are still with us and have wrought extensive havoc worldwide. There are many differences between these two infections and their global impacts, but one thing they have in common is the mobilization of scientific resources to both understand the infection and develop ways to combat it. As was the case with HIV, statisticians have been in the forefront of scientists working to understand transmission dynamics and the natural history of infection, determine prognostic factors for severe disease, and develop optimal study designs to assess therapeutics and vaccines.

Dried blood spots for the quantitative evaluation of IgG isotypes and correlation with serum samples in HIV-exposed uninfected (HEU) infants

BACKGROUND

The determination of IgG levels and their subclasses can provide clinically relevant information on the status of the immune system. Here we determined the sensitivity and reproducibility of the quantification of IgG subclasses from Dried Blood Spots (DBS) in Malawian uninfected infants exposed to HIV (HEU).

METHODS

Sixty paired samples of serum and DBS from HEU infants were used. Samples were collected from 1, 6, and 24-month old infants. IgGs concentrations from both serum and DBS were analyzed by BN ProSpec Siemens assay, using a different setting for sample dilutions. The reproducibility of the DBS method was tested on 10 samples run twice, starting from the DBS extraction process. To assess the systematic, proportional, and random differences, we computed the Passing-Bablok regression, and the Bland-Altman analysis to estimate the total mean bias between the two tests.

RESULTS

The IgG isotypes concentrations from serum and DBS showed significant differences in all the comparisons. Generally, the DBS method underestimated IgG subclasses' values showing a recovery range between 51.2% and 77.6%. Passing Bablok regression on age-based groups showed agreement for IgG, IgG1, and IgG2, but not for IgG3 and IgG4. The mean bias obtained with the Bland Altman test varied largely depending on IgG isotypes (-0.02-2.21 g/l) Coefficient of variation <7.0% was found in the repeated tests for IgG, IgG1, IgG3, and IgG4, while it was 12.4% for IgG2.

CONCLUSIONS

Varying degrees of differences were seen in the IgGs measurement in the two different matrices. In IgGs analysis, the DBS method offers promise for population-based research, but the results should be carefully evaluated and considered as a relative value since they are not equivalent to the serum concentrations.

Implementation of Universal HIV Testing and Treatment to Reduce HIV Incidence in Botswana: the Ya Tsie Study

PURPOSE OF REVIEW

Antiretroviral treatment (ART) can dramatically reduce the risk of HIV transmission, but the feasibility of scaling up HIV testing, linkage and treatment to very high population levels, and its impact on population HIV incidence, were unknown. We review key findings from a community-randomized trial in which we evaluated the impact of "universal test and treat" (UTT) on population HIV incidence in Botswana, a resource-constrained country with both high HIV prevalence and high ART coverage before study inception.

RECENT FINDINGS

We conducted a community-randomized trial (the "Ya Tsie" trial or Botswana Combination Prevention Project (BCPP)) in 30 villages in Botswana from 2013 to 2018, with the goal of determining whether a combination of prevention interventions-with a focus on universal HIV testing and treatment-would reduce population-level HIV incidence. The intervention included universal HIV testing (home-based and mobile), active linkage to HIV care and treatment with patient tracing for persons not linking, universal ART coverage, rapid ART start (at the first clinic visit), and enhanced male circumcision services. Botswana had very high HIV diagnosis, treatment, and viral suppression levels (approaching the UNAIDS "90-90-90" targets) prior to intervention roll-out. By study end, we were able to exceed the overall 95-95-95 coverage target of 86%: an estimated 88% of all persons living with HIV were on ART and had viral suppression in the Ya Tsie intervention arm. In addition, annual HIV incidence was 30% lower in the intervention arm as compared with the control arm over a 29-month follow-up period. With universal HIV testing and relatively simple linkage activities, it was possible to achieve one of the highest reported population levels of HIV diagnosis, linkage to care, and viral suppression globally and to reduce population HIV incidence by about one-third over a short period of time (< 3 years). We were able to significantly increase population viral suppression and to decrease HIV incidence even in a resource-constrained setting with pre-existing very high testing and treatment coverage. Universal community-based HIV testing and tracing of individuals through the HIV care cascade were key intervention components.