Validation of a screening tool to identify older children living with HIV in primary care facilities in high HIV prevalence settings

Public health implications of diagnosing and treating acute HIV

PURPOSE OF REVIEW

The earliest months of HIV infection are characterized by high viral loads and elevated transmissibility, particularly during the acute (preseroconversion) phase. Transmission prevention during early HIV requires diagnostic tools that narrow the window between viral acquisition and reactive test, followed by rapid linkage to effective antiretroviral therapy (ART). Here, we review recent advances related to diagnosing and treating persons during early HIV, with a particular focus on acute HIV infection (AHI).

RECENT FINDINGS

Point-of-care (POC) fourth-generation antigen/antibody tests have mixed performance, often dependent on the pretest probability of early infection within the screened population. Risk score algorithms demonstrate the potential for prioritizing resource-intensive tests, such as POC HIV RNA, to those most likely to have AHI, but their predictive performance varies across populations, complicating implementation. Emerging and re-emerging infections, including SARS-CoV-2 and mpox, present opportunities for and challenges to symptom-driven AHI screening. Daily oral ART with standard first-line regimens quickly suppresses viremia during AHI, but long-acting injectable drugs are yet to be explored for this indication.

SUMMARY

Few practice-changing results related to diagnosing or treating persons with early HIV have been released in the last 18 months. Accurate POC HIV RNA tests could leapfrog fourth-generation POC assays, but they remain unavailable for routine use. Implementation science approaches are needed to guide use of evidence-based strategies for early HIV screening, and additional research on same-day ART linkage, including injectable ART, could produce dramatic impacts on forward transmission during this period.

Assessment of a screening tool to aid home-based identification of adolescents (aged 10-14) living with HIV in Zambia and South Africa: HPTN 071 (PopART) study

INTRODUCTION

The HPTN071 (PopART) for Youth (P-ART-Y) study evaluated the acceptability and uptake of a community-level combination HIV prevention package including universal testing and treatment (UTT) among young people in Zambia and South Africa. We determined whether a four-question primary care level screening tool, validated for use in clinical settings, could enhance community (door-to-door) identification of undiagnosed HIV-positive younger adolescents (aged 10-14) who are frequently left out of HIV interventions.

METHOD

Community HIV-care Providers (CHiPs) contacted and consented adolescents in their homes and offered them participation in the PopART intervention. CHiPs used a four question-screening tool, which included: history of hospital admission; recurring skin problems; poor health in last 3 months; and death of at least one parent. A "yes" response to one or more questions was classified as being "at risk" of being HIV-positive. Rapid HIV tests were offered to all children. Data were captured through an electronic data capture device from August 2016 to December 2017. The sensitivity, specificity, positive predictive value and negative predictive value were estimated for the screening tool, using the rapid HIV test result as the gold standard.

RESULTS

In our 14 study sites, 33,710 adolescents aged 10-14 in Zambia and 8,610 in South Africa participated in the study. About 1.3% (427/33,710) and 1.2% (106/8,610) self-reported to be HIV positive. Excluding the self-reported HIV-positive, we classified 11.3% (3,746/33,283) of adolescents in Zambia and 17.5% (1,491/8,504) in South Africa as "at risk". In Zambia the estimated sensitivity was 35.3% (95% CI 27.3%-44.2%) and estimated specificity was 88.9% (88.5%-89.2%). In South Africa the sensitivity was 72.3% (26.8%-94.9%) and specificity was 82.5% (81.6-83.4%).

CONCLUSION

The sensitivity of the screening tool in a community setting in Zambia was low, so this tool should not be considered a substitute for universal testing where that is possible. In South Africa the sensitivity was higher, but with a wide confidence interval. Where universal testing is not possible the tool may help direct resources to adolescents more likely to be living with undiagnosed HIV.

TRIAL REGISTRATION

Clinical Trial Number: NCT01900977.

A Single Question on Maternal HIV Status Can Improve Identification of Children Living With HIV in South Africa

INTRODUCTION

Screening tools to improve identification of children living with HIV (CLHIV) have been validated and used in various settings. The aim of our study was to optimize a screening tool for Primary Healthcare Clinics (PHCs) in South Africa (SA).

METHODS

A cross-sectional study was conducted at PHCs in Johannesburg and Mopani Districts, between June 2021 and June 2022. Children 5-14 years of age with HIV negative or unknown status accompanied by their mothers, or appropriate caregivers, were enrolled. Demographic data, responses to the screening tool questions, and HIV test results were captured. Logistic regression modeling was used to optimize an existing 10-item screening tool, and sensitivity, specificity, and number needed to test (NNT) used to choose the final tool.

RESULTS

We enrolled 14,147 children in the study, with 62 children testing HIV positive (HIV positivity of 0.4%). The 10-item tool with a single positive response had a sensitivity of 91.9% and specificity of 43.3%. An optimal combination of 5-items with two positive responses had the lowest NNT of 72, 82.3% sensitivity and 74.2% specificity. Maternal HIV status alone, HIV positive or unknown, had a 95.2% sensitivity, 65.0% specificity and NNT of 84. The 1-item tool only would have missed 5% of CLHIV (N = 3) compared with the 5-item tool that missed 18% (n = 11).

CONCLUSIONS

A 1-item screening tool asking about maternal HIV status can improve efficiency of testing of children in primary healthcare facilities in SA and improve identification of CLHIV who are not on treatment.

Optimizing and validating a pediatric screening tool to more efficiently test and identify children living with HIV

OBJECTIVE

To develop and validate a screening tool to improve testing efficiency and increase case finding of children living with HIV.

DESIGN

Cross-sectional study.

METHODS

Between November 2020 and September 2021, children 18 months to 14 years presenting at outpatient departments in 30 health facilities in Zambia were administered a 14-question pediatric HIV screening tool and then tested for HIV. Data were analyzed using a randomly extracted 'validation' dataset and multivariable logistic regression to determine the highest performing and optimal number of screening questions. The final tool was then evaluated in the 'test' dataset. Sensitivity and specificity were calculated for both datasets. The final tool was then also implemented in 12 additional facilities to determine operational feasibility and uptake.

RESULTS

A total of 9902 children were included in the final analysis. HIV prevalence was 1.3%. Six questions were significantly associated with HIV-positivity. The optimal screening cutoff score was to answer 'yes' to one or more of the six questions; using this cutoff sensitivity was 92.5% [95% confidence interval (CI) 85.7-96.7%] and specificity was 62.9% (95% CI 61.9-64%). In the test dataset, the same tool had a sensitivity of 84.6% (95% CI 65.1-95.6%) and specificity of 64.6% (95% CI 62.4-66.7%). Uptake was 89%.

CONCLUSION

The results of this study show sensitivity and acceptable specificity in a six-question validated HIV screening tool. Implementing this screening tool in settings where universal testing is not feasible should more efficiently accelerate identification of children living with HIV (CLHIV) and their timely initiation onto life-saving drugs.

Acceptability and usability of a paediatric HIV screening tool in high-volume outpatient settings in Malawi, perspectives from caregivers and healthcare workers

BACKGROUND

Using an HIV pretest screening tool to identify children most at risk for HIV infection may be a more efficient and cost-effective approach to identify children living with HIV in resource-limited settings. These tools seek to reduce overtesting of children by increasing the positive predictive value while ensuring a high negative predictive value for those screened for HIV.

METHODS

This qualitative study in Malawi evaluated acceptability and usability of a modified version of the Zimbabwe HIV screening tool to identify children aged 2-14 years most-at-risk. The tool included additional questions about previous hospitalisations due to malaria and prior documented diagnoses. Sixteen interviews were conducted with expert clients (ECs), trained peer-supporters, which administered the screening tool and 12 interviews with biological and non-biological caregivers of screened children. All interviews were audiorecorded, transcribed and translated. Transcripts were analysed manually using a short-answer analysis, compiling responses for each question by study participant group. Summary documents were generated, identifying common and outlier perspectives.

RESULTS

The HIV paediatric screening tool was generally accepted by caregivers and ECs, with both groups seeing the benefit of the tool and promoting its use. The ECs who were primarily responsible for implementing the tool initially struggled with acceptance of the tool but started to accept it after additional training and mentorship was provided. Overall, caregivers accepted having their children tested for HIV, although non-biological caregivers expressed hesitancy in giving consent for HIV testing. ECs reported challenges with the ability for non-biological caregivers to answer some questions.

CONCLUSION

This study found general acceptance of paediatric screening tools in children in Malawi and identified some minor challenges that raise important considerations for tool implementation. These include the need for a thorough orientation of the tools for the healthcare workers and caregivers, appropriate space at the facility, and adequate staffing and commodities.

Considerations to Improve Pediatric HIV Testing and Close the Treatment Gap in 16 African Countries

BACKGROUND

In 2019, South Africa, Nigeria, Tanzania, Democratic Republic of Congo, Uganda, Mozambique, Zambia, Angola, Cameroon, Zimbabwe, Ghana, Ethiopia, Malawi, Kenya, South Sudan and Côte d'Ivoire accounted for 80% of children living with HIV (CLHIV) not receiving HIV treatment. This manuscript describes pediatric HIV testing to inform case-finding strategies.

METHODS

We analyzed US President's Emergency Plan for AIDS Relief monitoring, evaluation, and reporting data (October 1, 2018 to September 30, 2019) for these 16 countries. Number of HIV tests and positive results were reported by age band, country, treatment coverage and testing modality. The number needed to test (NNT) to identify 1 new CLHIV 1-14 years was measured by testing modality and country. The pediatric testing gap was estimated by multiplying the estimated number of CLHIV unaware of their status by NNT per country.

RESULTS

Among children, 6,961,225 HIV tests were conducted, and 101,762 CLHIV were identified (NNT 68), meeting 17.6% of the pediatric testing need. Index testing accounted for 13.0% of HIV tests (29.7% of positive results, NNT 30), provider-initiated testing and counseling 65.9% of tests (43.6% of positives, NNT 103), and universal testing at sick entry points 5.3% of tests (6.5% of positives, NNT 58).

CONCLUSIONS

As countries near HIV epidemic control for adults, the need to increase pediatric testing continues. Each testing modality - PITC, universal testing at sick entry points, and index testing - offers unique benefits. These results illustrate the comparative advantages of including a strategic mix of testing modalities in national programs to increase pediatric HIV case finding.

Adapting strategies for effective and efficient pediatric HIV case finding in low prevalence countries: risk screening tool for testing children presenting at high-risk entry points in Ethiopia

Background

Implementing effective and efficient case-finding strategies is crucial to increasing pediatric antiretroviral therapy coverage. In Ethiopia, universal HIV testing is conducted for children presenting at high-risk entry points including malnutrition treatment, inpatient wards, tuberculosis (TB) clinics, index testing for children of positive adults, and referral of orphans and vulnerable children (OVC); however, low positivity rates observed at inpatient, malnutrition and OVC entry points warrant re-assessing current case-finding strategies. The aim of this study is to develop HIV risk screening tool applicable for testing children presenting at inpatient, malnutrition and OVC entry points in low-HIV prevalence settings.

Methods

The study was conducted from May 2017–March 2018 at 29 public health facilities in Amhara and Addis Ababa regions of Ethiopia. All children 2–14 years presenting to five high-risk entry points including malnutrition treatment, inpatient wards, tuberculosis (TB) clinics, index testing for children of positive adults, and referral of orphans and vulnerable children (OVC) were enrolled after consent. Data were collected from registers, medical records, and caregiver interviews. Screening tools were constructed using predictors of HIV positivity as screening items by applying both logistic regression and an unweighted method. Sensitivity, specificity and number needed to test (NNT) to identify one new child living with HIV (CLHIV) were estimated for each tool.

Results

The screening tools had similar sensitivity of 95%. However, the specificities of tools produced by logistic regression methods (61.4 and 65.6%) which are practically applicable were higher than those achieved by the unweighted method (53.6). Applying these tools could result in 58‒63% reduction in the NNT compared to universal testing approach while maintaining the overall number of CLHIV identified.

Conclusion

The screening tools developed using logistic regression method could significantly improve HIV testing efficiency among children presenting to malnutrition, inpatient, and OVC entry points in Ethiopia while maintaining case identification. These tools are simplified to practically implement and can potentially be validated for use at various entry points. HIV programs in low-prevalence countries can also further investigate and optimize these tools in their settings.

Risk-Based Screening Tools to Optimise HIV Testing Services: a Systematic Review

PURPOSE OF REVIEW

Effective ways to diagnose the remaining people living with HIV who do not know their status are a global priority. We reviewed the use of risk-based tools, a set of criteria to identify individuals who would not otherwise be tested (screen in) or excluded people from testing (screen out).

RECENT FINDINGS

Recent studies suggest that there may be value in risk-based tools to improve testing efficiency (i.e. identifying those who need to be tested). However, there has not been any systematic reviews to synthesize these studies. We identified 18,238 citations, and 71 were included. The risk-based tools identified were most commonly from high-income (51%) and low HIV (<5%) prevalence countries (73%). The majority were for "screening in" (70%), with the highest performance tools related to identifying MSM with acute HIV. Screening in tools may be helpful in settings where it is not feasible or recommended to offer testing routinely. Caution is needed for screening out tools, where there is a trade-off between reducing costs of testing with missing cases of people living with HIV.

Cost-effectiveness of Routine Provider-Initiated Testing and Counseling for Children With Undiagnosed HIV in South Africa

BACKGROUND

We compared the cost-effectiveness of pediatric provider-initiated HIV testing and counseling (PITC) vs no PITC in a range of clinical care settings in South Africa.

METHODS

We used the Cost-Effectiveness of Preventing AIDS Complications Pediatric model to simulate a cohort of children, aged 2-10 years, presenting for care in 4 settings (outpatient, malnutrition, inpatient, tuberculosis clinic) with varying prevalence of undiagnosed HIV (1.0%, 15.0%, 17.5%, 50.0%, respectively). We compared "PITC" (routine testing offered to all patients; 97% acceptance and 71% linkage to care after HIV diagnosis) with no PITC. Model outcomes included life expectancy, lifetime costs, and incremental cost-effectiveness ratios (ICERs) from the health care system perspective and the proportion of children with HIV (CWH) diagnosed, on antiretroviral therapy (ART), and virally suppressed. We assumed a threshold of $3200/year of life saved (YLS) to determine cost-effectiveness. Sensitivity analyses varied the age distribution of children seeking care and costs for PITC, HIV care, and ART.

RESULTS

PITC improved the proportion of CWH diagnosed (45.2% to 83.2%), on ART (40.8% to 80.4%), and virally suppressed (32.6% to 63.7%) at 1 year in all settings. PITC increased life expectancy by 0.1-0.7 years for children seeking care (including those with and without HIV). In all settings, the ICER of PITC vs no PITC was very similar, ranging from $710 to $1240/YLS. PITC remained cost-effective unless undiagnosed HIV prevalence was <0.2%.

CONCLUSIONS

Routine testing improves HIV clinical outcomes and is cost-effective in South Africa if the prevalence of undiagnosed HIV among children exceeds 0.2%. These findings support current recommendations for PITC in outpatient, inpatient, tuberculosis, and malnutrition clinical settings.

Finding Children Living With HIV in Low-prevalence Countries: HIV Prevalence and Testing Yield From 5 Entry Points in Ethiopia

BACKGROUND

Limited data in low HIV prevalence settings such as Ethiopia limit policy development and implementation of optimized pediatric testing approaches to close the treatment gap. This study aimed to determine HIV prevalence, testing yield and factors associated with HIV among children at 5 entry points.

METHODS

We conducted a cross-sectional study from May 2017 to March 2018 in 29 public health facilities in Amhara and Addis Ababa regions in Ethiopia. Children 2-14 years were enrolled through 5 entry points. Data were obtained from registers, medical records and interviews with caregivers. HIV prevalence and testing yields were calculated for each entry point. Mixed-effects logistic regression analysis identified factors associated with undiagnosed HIV.

RESULTS

The study enrolled 2166 children, of whom 94 were HIV positive (40 newly diagnosed). HIV prevalence and testing yield were the highest among children of HIV-positive adults (index testing; 8.2% and 8.2%, respectively) and children presenting to tuberculosis clinics (7.9% and 1.8%) or with severe malnutrition (6.5% and 1.4%). Factors associated with undiagnosed HIV included tuberculosis or index entry point [adjusted odds ratio (aOR), 11.97; 95% CI 5.06-28.36], deceased mother (aOR 4.55; 95% CI 1.30-15.92), recurrent skin problems (aOR 17.71; 95% CI 7.75-40.43), severe malnutrition (aOR 4.56; 95% CI 2.04-10.19) and urban residence (aOR 3.47; 95% CI 1.03-11.66).

CONCLUSIONS

Index testing is a critical strategy for pediatric case finding in Ethiopia. Strategies and resources can prioritize minimizing missed opportunities in implementing universal testing for very sick children (tuberculosis, severe malnutrition) and implementing targeted testing in other entry points through use of factors associated with HIV.

Treatment-adjusted prevalence to assess HIV testing programmes

Scale-up of human immunodeficiency virus (HIV) testing and antiretroviral therapy (ART) for people living with HIV has been increasing in sub-Saharan Africa. As a result, areas with high HIV prevalence are finding a declining proportion of people testing positive in their national testing programmes. In eastern and southern Africa, where there are settings with adult HIV prevalence of 12% and above, the positivity from national HIV testing services has dropped to below 5%. Identifying those in need of ART is therefore becoming more costly for national HIV programmes. Annual target-setting assumes that national testing positivity rates approximate that of population prevalence. This assumption has generated an increased focus on testing approaches which achieve higher rates of HIV positivity. This trend is a departure from the provider-initiated testing and counselling strategy used early in the global HIV response. We discuss a new indicator, treatment-adjusted prevalence, that countries can use as a practical benchmark for estimating the expected adult positivity in a testing programme when accounting for both national HIV prevalence and ART coverage. The indicator is calculated by removing those people receiving ART from the numerator and denominator of HIV prevalence. Treatment-adjusted prevalence can be readily estimated from existing programme data and population estimates, and in 2019, was added to the World Health Organization guidelines for HIV testing and strategic information. Using country examples from Kenya, Malawi, South Sudan and Zimbabwe we illustrate how to apply this indicator and we discuss the potential public health implications of its use from the national to facility level.

Developing and Validating an Effective Pediatric and Adolescent HIV Testing Eligibility Screening Tool for High-Volume Entry Points in Uganda

INTRODUCTION

Because of low pediatric HIV prevalence, more tests are needed to find 1 HIV-positive child compared with adults. In Uganda, the number needed to test (NNT) to find 1 new HIV-positive child was 64 in outpatient departments (OPDs) and 31 through index testing. We aimed to develop and validate a pediatric (1.5-14 years) screening tool to optimize testing approaches.

METHODS

Phase 1 evaluated the performance of 10 screening questions in 14 OPDs using a variable selection algorithm to evaluate combinations of screening questions. Using logistic regression, we identified the number of screening questions with the best predictive accuracy using the receiver operation characteristic curve. Phase 2 validated the proposed tool in 15 OPDs and 7 orphan and vulnerable children programs. We estimated sensitivity, specificity, and NNT accounting for intercluster correlations.

RESULTS

A total of 3482 children were enrolled. The optimal model included reported HIV-positive maternal status or 2/5 symptoms (sickly in the last 3 months, recurring skin problems, weight loss, not growing well, and history of tuberculosis). The proposed tool had sensitivity of 83.6% [95% confidence interval (CI): 68.1 to 92.4] and specificity of 62.5% (95% CI: 55.0 to 69.4). The tool was validated in a sample of 11,342 children; sensitivity was 87.8% (95% CI: 80.9 to 92.5) and specificity 62.6% (95% CI: 54.8 to 69.7) across OPDs and community sites. In OPDs, sensitivity was 88.1% (95% CI: 80.8 to 92.8) and specificity 69.0% (95% CI: 61.9 to 75.3). The NNT was 43 (95% CI: 28 to 67) across settings and 28 (95% CI: 20 to 38) for OPD.

CONCLUSIONS

This HIV screening tool has high sensitivity and reasonable specificity, increasing testing efficiency and yield for children and adolescents.

Balancing HIV testing efficiency with HIV case-identification among children and adolescents (2-19 years) using an HIV risk screening approach in Tanzania

To optimize HIV testing resources, programs are moving away from universal testing strategies toward a risk-based screening approach to testing children/adolescents, but there is little consensus around what defines an optimal risk screening tool. This study aimed to validate a 12-item risk screening tool among children and adolescents and provide suggested fewer-item tool options for screening both facility out-patient and community populations by age strata (<10 and ≥10 years). Children/adolescents (2–19 years) with unknown HIV status were recruited from a community-based vulnerable children program and health facilities in 5 regions of Tanzania in 2019. Lay workers administered the screening questions to caregivers/adolescents; nurses enrolled those eligible for the study and tested all participants for HIV. For each screening item, we estimated sensitivity, specificity, positive predictive value and negative predictive value and associated 95% confidence intervals (CI). We generated a score based on the count of items with a positive risk response and fit a receiver operating characteristic curve to determine a cut-off score. Sensitivity, specificity, positive predictive value (PPV; yield) and number needed to test to detect an HIV-positive child (NNT) were estimated for various tool options by age group. We enrolled 21,008 children and adolescents. The proportion of undiagnosed HIV-positive children was low (n = 76; 0.36%; CI:0.29,0.45%). A screening algorithm based on reporting at least one or more items on the 10 to 12-item tool had sensitivity 89.2% (CI:79.1,95.6), specificity 37.5% (CI:36.8,38.2), positive predictive value 0.5% (CI:0.4,0.6) and NNT = 211. An algorithm based on at least two or more items resulted in lower sensitivity (64.6%), improved specificity (69.1%), PPV (0.7%) and NNT = 145. A shorter tool derived from the 10 to 12-item screening tool with a score of “1” or more on the following items: relative died, ever hospitalized, cough, family member with HIV, and sexually active if 10–19 years performed optimally with 85.3% (CI:74.6,92.7) sensitivity, 44.2% (CI:43.5,44.9) specificity, 0.5% (CI:0.4,0.7) PPV and NNT = 193. We propose that different short-tool options (3–5 items) can achieve an optimal balance between reduced HIV testing costs (lower NNT) with acceptable sensitivity. In low prevalence settings, changes in yield may be negligible and NNT may remain high even for an effective tool.

HIV risk screening and HIV testing among orphans and vulnerable children in community settings in Tanzania: Acceptability and fidelity to lay-cadre administration of the screening tool

INTRODUCTION

HIV risk screening tool validation studies have not typically included process evaluations to understand tool implementation. The study aim was to assess the fidelity to which an HIV risk screening tool was administered by lay workers and acceptability of delivering home-based screening coupled with HIV testing to beneficiaries in an orphans and vulnerable children (OVC) program.

METHODS

This cross-sectional study was conducted March-April 2019 in two regions of Tanzania. Community case workers (CCW) were observed conducting screenings with OVC 2-19 years and participated in focus group discussions. Research staff used structured observation checklists to capture if screening questions were asked or reworded by CCW. In-depth interviews were conducted with older adolescents and caregivers in their homes following screening and testing. A composite score was developed for the checklist. Qualitative data were thematically analyzed to address screening and testing perceptions and experiences.

RESULTS

CCW (n = 32) participated in 166 observations. Commonly skipped items were malnutrition (34% of all observed screenings) and sexual activity and pregnancy (20% and 45% of screenings for adolescents only). Items frequently re-worded included child abuse (22%) and malnutrition (15%). CCW had an average composite observation score of 42/50. CCW in focus groups (n = 34) found the screening process acceptable. However, they described rewording some questions viewed as harsh or socially inappropriate to ask. Overall, adolescent beneficiaries (n = 17) and caregivers (n = 25) were satisfied with home-based screening and testing and reported no negative consequences. Learning one's HIV negative status was seen as an opportunity to discuss or recommit to healthy behaviors. While respondents identified multiple benefits of home testing, they noted the potential for privacy breaches in household settings.

CONCLUSIONS

We found sub-optimal fidelity to the administration of the screening tool by CCW in home environments to children and adolescents enrolled in an OVC program. Improvements to questions and their delivery and ongoing mentorship could strengthen tool performance and HIV case finding using a targeted testing approach. Overall, home-based HIV risk screening and testing were acceptable to beneficiaries and CCW, could improve testing uptake, and serve as a platform to promote healthy behaviors for those with limited health system interactions.

Comparison of index-linked HIV testing for children and adolescents in health facility and community settings in Zimbabwe: findings from the interventional B-GAP study

BACKGROUND

Index-linked HIV testing, whereby children of individuals with HIV are targeted for testing, increases HIV yield but relies on uptake. Community-based testing might address barriers to testing access. In the Bridging the Gap in HIV testing and care for children in Zimbabwe (B-GAP) study, we investigated the uptake and yield of index-linked testing in children and the uptake of community-based vs facility-based HIV testing in Zimbabwe.

METHODS

B-GAP was an interventional study done in the city of Bulawayo and the province of Matabeleland South between Jan 29 and Dec 12, 2018. All HIV-positive attendees (index patients) at six urban and three rural primary health-care clinics were offered facility-based or community-based HIV testing for children (age 2-18 years) living in their households who had never been tested or had tested as HIV-negative more than 6 months ago. Community-based options involved testing in the home by either a trained lay worker with a blood-based rapid diagnostic test (used in facility-based testing), or by the child's caregiver with an oral HIV test. Among consenting individuals, the primary outcome was testing uptake in terms of the proportion of eligible children tested. Secondary outcomes were uptake of the different HIV testing methods, HIV yield (proportion of eligible children who tested positive), and HIV prevalence (proportion of HIV-positive children among those tested). Logistic regression adjusting for within-index clustering was used to investigate index patient and child characteristics associated with testing uptake, and the uptake of community-based versus facility-based testing.

FINDINGS

Overall, 2870 index patients were linked with 6062 eligible children (3115 [51·4%] girls [sex unknown in seven], median age 8 years [IQR 5-13]). Testing was accepted by index patients for 5326 (87·9%) children, and 3638 were tested with a known test outcome, giving an overall testing uptake among 6062 eligible children of 60·0%. 39 children tested positive for HIV, giving an HIV prevalence among the 3638 children of 1·1% and an HIV yield among 6062 eligible children of 0·6%. Uptake was positively associated with female sex in the index patient (adjusted odds ratio [aOR] 1·56 [95% CI 1·38-1·77], p<0·0001) and child (aOR 1·10 [1·03-1·19], p=0·0080), and negatively associated with any financial cost of travel to a clinic (aOR 0·86 [0·83-0·88], p<0·0001), increased child age (6-9 years: aOR 0·99 (0·89-1·09); 10-15 years: aOR 0·91 [0·83-1·00]; and 16-18 years: aOR 0·75 [0·66-0·85]; p=0·0001 vs 2-5 years), and unknown HIV status of the mother (aOR 0·81 [0·68-0·98], p=0·027 vs HIV-positive status). Additionally, children had increased odds of being tested if community-based testing was chosen over facility-based testing at screening (1320 [73·9%] children tested of 1787 vs 2318 [65·5%] of 3539; aOR 1·49 [1·22-1·81], p=0·0001).

INTERPRETATION

The HIV yield of index-linked testing was low compared with blanket testing approaches in similar settings. Index-linked HIV testing can improve testing uptake among children, although strategies that improve testing uptake in older children are needed. Community based testing by lay workers is a feasible strategy that can be used to improve uptake of HTS among children and adolescents.

FUNDING

UK Medical Research Council, UK Department for International Development, Wellcome Trust.

Development and Validation of a Sociodemographic and Behavioral Characteristics-Based Risk-Score Algorithm for Targeting HIV Testing Among Adults in Kenya

To inform targeted HIV testing, we developed and externally validated a risk-score algorithm that incorporated behavioral characteristics. Outpatient data from five health facilities in western Kenya, comprising 19,458 adults ≥ 15 years tested for HIV from September 2017 to May 2018, were included in univariable and multivariable analyses used for algorithm development. Data for 11,330 adults attending one high-volume facility were used for validation. Using the final algorithm, patients were grouped into four risk-score categories: ≤ 9, 10-15, 16-29 and ≥ 30, with increasing HIV prevalence of 0.6% [95% confidence interval (CI) 0.46-0.75], 1.35% (95% CI 0.85-1.84), 2.65% (95% CI 1.8-3.51), and 15.15% (95% CI 9.03-21.27), respectively. The algorithm's discrimination performance was modest, with an area under the receiver-operating-curve of 0.69 (95% CI 0.53-0.84). In settings where universal testing is not feasible, a risk-score algorithm can identify sub-populations with higher HIV-risk to be prioritized for HIV testing.

Implementation of blanket provider-initiated testing and counselling: Predictors of HIV seropositivity among infants, children and adolescents in Cameroon

Objectives

Study design

Methods

Results

Conclusions

•

Methods to increase the yield of PITC remain unclear.

•

HIV seropositivity predictors could improve PITC yield.

•

Identifying HIV seropositivity predictors among children and adolescents.

•

Targeted HIV testing to improve PITC yield in HIV high burden countries.

•

HIV seropositivity predictors could reduce gap in pediatric and adolescent ART.

Screening Algorithms to Reduce Burden of Pediatric HIV Testing: A Systematic Review and Meta-analysis

BACKGROUND

The accuracy of symptom screening to identify children eligible for further HIV testing in generalized epidemics has been examined in several studies. We performed a systematic review and meta-analysis of these studies.

METHODS

We screened 5 databases and abstracts from 4 HIV/AIDS conferences. Studies were included if they were performed in clinical settings, included children of 0-15 years old, and used a signs/symptoms screen to determine eligibility for HIV testing. The primary outcomes were sensitivity and specificity of the screening tools. A meta-analysis was performed to evaluate the utility of a screening tool in the outpatient setting.

RESULTS

Our search returned 5529 database results and approximately 6700 conference abstracts, of which 36 articles were reviewed and 7 met criteria for inclusion. All were prospective or cross-sectional studies that developed and/or validated a screening tool to identify children at higher risk for being HIV infected. Sensitivity of the screening tools ranged from 71% to 96%, whereas specificity ranged from 25% to 99%. Meta-analysis of studies evaluating outpatient screening tools revealed a sensitivity of 81.4%, with a specificity of 69.4% for detecting HIV infection.

CONCLUSIONS

Few studies have evaluated the use of screening tools for HIV diagnosis in children. Screening tools that exist showed only moderate sensitivity and specificity and missed a substantial number of HIV-infected children in high-prevalence areas. In outpatient settings, the use of a screening tool may help reduce the number of HIV tests needed to identify an HIV-infected child, but at the cost of missed diagnoses. Further studies are needed to determine whether this represents a resource-saving mechanism.

Increasing pediatric HIV testing positivity rates through focused testing in high-yield points of service in health facilities-Nigeria, 2016-2017

Background

In 2017, UNAIDS estimated that 140,000 children aged 0–14 years are living with HIV in Nigeria, but only 35% have been diagnosed and are receiving antiretroviral therapy. Children are tested primarily in outpatient clinics, which show low HIV-positive rates. To demonstrate efficient facility-based HIV testing among children aged 0–14 years, we evaluated pediatric HIV-positivity rates in points of service in select health facilities in Nigeria.

Methods

We conducted a retrospective analysis of HIV testing and case identification among children aged 0–14 years at all points of service at nine purposively sampled hospitals (November 2016–March 2017). Points of service included family index testing, pediatric outpatient department (POPD), tuberculosis (TB) clinics, immunization clinics, and pediatric inpatient ward. Eligibility for testing at POPD was done using a screening tool while all children with unknown status were eligible for HIV test at other points of service. The main outcome was HIV positivity rates stratified by the testing point of service and by age group. Predictors of an HIV-positive result were assessed using logistic regression. All analyses were done using Stata 15 statistical software.

Results

Of 2,180 children seen at all facility points of service with unknown HIV status, 1,822 (83.6%) were tested for HIV, of whom 43 (2.4%) tested HIV positive. The numbers of children tested by age group were <1 years = 230 (12.6%); 1–4 years = 752 (41.3%); 5–9 years = 520 (28.5%); and 10–14 years = 320 (17.6%). The number of children tested by point of service were POPD = 906 (49.7%); family index testing = 693 (38.0%); pediatric inpatient ward = 192 (10.5%); immunization clinic = 16 (0.9%); and TB clinic = 15 (0.8%). HIV positivity rates by point of service were TB clinic = 6.7% (95% Confidence Interval (CI): 0.9–35.2%); pediatric inpatient ward = 4.7% (95%CI: 2.5–8.8%); family index testing = 3.5% (95%CI: 2.3–5.1%); POPD = 1.0% (95%CI: 0.5–1.9%); and immunization clinic = 0%. The percentage contribution to total HIV positive children found by point of services was: family index testing = 55.8% (95%CI: 40.9–69.8%); POPD = 20.9% (95%CI: 11.3–35.6%); inpatient ward = 20.9 (95%CI: 11.3–35.6%) and TB Clinic = 2.3% (95%CI: 0.3–14.8%). Compared with the POPD, the adjusted odds ratio (95% CI) for finding an HIV positive child by point of service were TB clinic = 7.2 (95% CI: 0.9–60.9); pediatric inpatient ward = 4.9 (95% CI: 1.9–12.8); and family index testing = 3.7 (95% CI: 1.5–8.8). HIV-positivity rates did not significantly differ by age group.

Conclusion

In Nigeria, to improve facility-based HIV positivity rates among children aged 0–14 years, an increased focus on HIV testing among children seeking care in pediatric inpatient wards, through family index testing, and perhaps TB clinics is appropriate.

Brief Report: Diagnostic Accuracy of Oral Mucosal Transudate Tests Compared with Blood-Based Rapid Tests for HIV Among Children Aged 18 Months to 18 Years in Kenya and Zimbabwe

Gaps persist in HIV testing for children who were not tested in prevention of mother-to-child HIV transmission programs. Oral mucosal transudate (OMT) rapid HIV tests have been shown to be highly sensitive in adults, but their performance has not been established in children.

Parental and child-level predictors of HIV testing uptake, seropositivity and treatment initiation among children and adolescents in Cameroon

Background

There is a growing body of evidence positioning targeted provider-initiated testing and counselling (tPITC, also known as index case testing) as a promising HIV case-finding and linkage strategy among children and adolescents. However, the effectiveness and efficiency of this strategy is limited by low HIV testing uptake and case detection rates. Despite this fact, there is very little literature on factors associated with HIV testing uptake, HIV seropositivity and ART-enrolment in tPITC implementation among African children. This study aims to bridge this information gap and contribute in improving the effectiveness and efficiency of tPITC among children and adolescents in Cameroon and beyond.

Methods

In three ART clinics where tPITC was previously inexistent, we introduced the routine implementation of this strategy by inviting parents living with HIV/AIDS in care to have their biological children (6 weeks-19 years) HIV-tested. Children of consenting parents were HIV-tested; those testing positive were enrolled on ART. Parental and child-level characteristics associated with HIV testing uptake, seropositivity and ART-enrollment were assessed using bivariate and multivariate regression analysis at 5% significance level.

Results

We enrolled 1,236 parents, through whom 1,990 children/adolescents were recruited for HIV testing. Among enrolled parents, 46.2% (571/1,236) had at least one child tested, and 6.8% (39/571) of these parents had at least one HIV-positive child. Among enrolled children/adolescents, 56.7% (1,129/1,990) tested for HIV and 3.5% (40/1129) tested HIV-positive. Parental predictors of HIV testing uptake among children/adolescents were sex, occupation and duration on ART: female [aOR = 1.6 (1.1–2.5)], office workers/students [aOR = 2.0 (1.2–3.3)], and parents with ART duration > 5 years [aOR = 2.0 (1.3–2.9)] had significantly higher odds to test a child than male, farmers/traders, and parents with ART duration < 5 years respectively. The only child-level predictor of testing uptake was age: children < 18 months [aOR = 5(2–10)] had significantly higher odds to test for HIV than adolescents > 15 years. Parents of children identified as HIV-positive were more likely to be female, aged 40–60 years, farmers/traders, widows/divorcees and not on ART. Children found HIV-positive and who were ART-enrolled were more likely to be female and aged 5–9 years. However, none of the above-mentioned associations was statistically significant.

Conclusions

Parents who were male, farmers/traders, and on ART for ≤ 5 years were less likely to test their children for HIV. Also, adolescents 10–19 years old were less likely to be tested. Therefore, these groups should be targeted with intensive counseling and follow-up to facilitate optimal testing uptake. No association was found between parental or child-level characteristics and HIV seropositivity among tested children. This finding prompts for further research to investigate approaches to better identify and target HIV testing to children/adolescents with the highest likelihood of HIV seropositivity.

Clinical trial registration

Reg: CinicalTrials.gov # NCT03024762.

Simple Screening Tool to Help Identify High-Risk Children for Targeted HIV Testing in Malawian Inpatient Wards

BACKGROUND

To meet global AIDS goals, pediatric HIV diagnosis must be strengthened. Provider-initiated testing and counseling, which is recommended by the WHO, faces persistent implementation challenges in low-resource settings. Alternative approaches are needed.

SETTING

Malawi has achieved high coverage of HIV diagnosis and treatment, but there are gaps among pediatric populations. This study assessed the sensitivity and specificity of a brief screening tool to identify at-risk pediatric patients for targeted HIV testing in Malawi.

METHODS

A tool containing 6 yes/no items was used for children (aged 1-15 years) in the inpatient pediatric wards at 12 hospitals in Malawi (July 2016-July 2017). Questions were based on an established tool, translated to Chichewa, and implemented by HIV diagnostic assistants. All participating children were provided HIV testing and counseling per Ministry of Health guidelines. Analysis estimated the tool's characteristics including sensitivity, specificity, negative, and positive predictive values.

RESULTS

HIV prevalence among the 8602 participants was 1.1% (n = 90). Children with a screening tool score of 1 had double the odds of being HIV positive than those with a score of 0. Frequent sickness was the most sensitive predictor of HIV status (55.1%), and having a deceased parent was the most specific (96.7%). False classification of HIV-negative status was rare (n = 14) but occurred more often among boys and younger children.

CONCLUSIONS

A brief screening tool for pediatric inpatients helped target HIV testing in those most at risk in a low-pediatric-prevalence, resource-constrained setting. Future research should include a direct, rigorous comparison with PITC including comparative effectiveness, efficiency, and cost effectiveness.

Clinical and operational factors associated with low pediatric inpatient HIV testing coverage in Mozambique

Setting

Eleven pediatric wards in Maputo Province, Mozambique.

Objective

1) To determine provider-initiated testing and counseling (PITC) coverage, the rate of human immunodeficiency virus (HIV) positivity, and the clinical and facility-level variables associated with PITC; and 2) to assess the care cascade for HIV-exposed and -infected children.

Design

This was a cross-sectional, retrospective review of inpatient charts, selected via systematic randomization, of patients aged 0-4 years, admitted between July and December 2015.

Results

Among the 800 patients included, the median age was 23 months and median duration of hospitalization was 3 days. HIV testing was ordered in 46.0% of eligible patients (known HIV-infected at admission excluded), with results documented for 35.7%, of whom 8.3% were positive. The patient hospitalization diagnoses with the highest PITC rates were malnutrition (73.8%), sepsis (71.4%) and tuberculosis (58.3%), with positivity rates of respectively 16.1%, 20.0%, and 28.6%. Longer hospitalization, weekday admission, and PITC training for staff were significantly associated with better PITC performance. Antiretroviral treatment was initiated during hospitalization for 29.6% of eligible patients.

Conclusion

PITC coverage was low, with high HIV positivity rates, highlighting missed opportunities for diagnosis and linkage to treatment. Strengthened routine testing on wards with consideration of inpatient ART initiation are needed to help achieve pediatric 90-90-90 goals.

Effectiveness of symptom-based diagnostic HIV testing versus targeted and blanket provider-initiated testing and counseling among children and adolescents in Cameroon

Objectives

The concurrent implementation of targeted (tPITC) and blanket provider-initiated testing and counselling (bPITC) is recommended by the World Health Organization (WHO) for HIV case-finding in generalized HIV epidemics. This study assessed the effectiveness of this intervention compared to symptom-based diagnostic HIV testing (DHT) in terms of HIV testing uptake, case detection and antiretroviral therapy (ART) enrollment among children and adolescents in Cameroon, where estimated HIV prevalence is relatively low at 3.7%.

Methods

In three hospitals where DHT was the standard practice before, tPITC and bPITC were implemented by inviting HIV-positive parents in care at the ART clinics to have their biological children (6 weeks-19 years) tested for HIV (tPITC). Concurrently, at the outpatient departments, similarly-age children/adolescents were systematically offered HIV testing via accompanying parents/guardians. The mean monthly number of children tested for HIV, identified HIV-positive and ART-enrolled were used to compare the outcomes of different HIV testing strategies before and after the intervention.

Results

In comparing DHT to bPITC, there was a significant increase in the mean monthly number of children/adolescents tested for HIV (223.0 vs 348.3, p = 0.0073), but with no significant increase in the mean monthly number of children/adolescents: testing HIV-positive (10.5 vs 9.7, p = 0.7574) and ART- enrolled (7.3 vs 6.3, p = 0.5819). In comparing DHT to tPITC, there was no significant difference in the mean monthly number of children/adolescents: tested for HIV (223 vs 193.8, p = 0.4648); tested HIV-positive (10.5 vs 10.6, p = 0.9544), and ART-enrolled (7.3 vs 5.8, p = 0.4672). When comparing DHT versus bPITC+tPITC, there was a significant increase in the mean monthly number of children/adolescents: tested for HIV (223.0 to 542.2, p<0.0001), testing HIV-positive (10.5 vs 20.3, p = 0.0256), and ART-enrolled (7.3 vs 12.2, p = 0.0388).

Conclusions

These findings suggest that concurrent implementation of bPITC+tPITC was more effective compared to DHT in terms of HIV testing uptake, case detection and ART enrolment. However, considering that DHT and bPITC had comparable outcomes with regards to case detection and ART enrolment, bPITC+tPITC may not be efficient. Thus, this finding does not support concurrent bPITC+tPITC implementation as recommended by WHO. Rather, continued DHT+tPITC could effectively and efficiently accelerate HIV case detection and ART coverage among children and adolescents in Cameroon and similar low-prevalence context.

Barriers to, and emerging strategies for, HIV testing among adolescents in sub-Saharan Africa

PURPOSE OF REVIEW

HIV/AIDS is one of the leading causes of death among adolescents in sub-Saharan Africa and 40% of new HIV infections worldwide occur in this group. HIV testing and counselling (HTC) is the critical first step to accessing HIV treatment. The prevalence of undiagnosed HIV infection is substantially higher in adolescents compared with adults. We review barriers to HTC for adolescents and emerging HTC strategies appropriate to adolescents in sub-Saharan Africa.

RECENT FINDINGS

There are substantial individual, health system and legal barriers to HTC among adolescents, and stigma by providers and communities remains an important obstacle. There has been progress made in recent years in developing strategies that address some of these barriers, increase uptake of HTC and yield of HIV. These include targeted approaches focused on provision of HTC among those higher risk of being infected, for example, index-linked HTC and use of screening tools to identify those at risk of HIV. Community-based HIV-testing approaches including HIV self-testing and incentives have also been shown to increase uptake of HTC.

SUMMARY

In implementing HTC strategies, consideration must be given to scalability and cost-effectiveness. HTC approaches must be coupled with linkage to appropriate care and prevention services.

Screening tool to identify adolescents living with HIV in a community setting in Zimbabwe: A validation study

INTRODUCTION

A simple cost-effective strategy to pre-screen for targeted HIV testing can have substantial benefit in high burden and resource limited settings. A 4-item (previous hospitalisation, orphanhood, poor health status, and recurring skin problems) screening tool to identify adolescents living with HIV has previously shown high sensitivity in healthcare facility settings. We validated this screening tool in a community setting, in Harare, Zimbabwe in a community-based HIV prevalence survey.

METHODS

A community-based HIV prevalence survey was conducted among individuals aged 8-17 years with guardian consent and child assent and residing in 7 communities during the period February 2015 to December 2015. Participants without previously diagnosed HIV were evaluated for the probability of having HIV using the screening tool. HIV status was defined using an anonymous HIV test which was done using Oral Mucosal Transudate (OMT). A questionnaire was also administered to ascertain self-reported HIV status and screening tool items. The validity of a 4-item screening tool was tested. Sensitivity and specificity of the screening tool was assessed against the HIV status based on OMT result.

RESULTS

Prevalence survey participants were 5386 children who had an HIV test result, aged 8-17 years. However, 5384, who did not report testing HIV positive and responded to all screening tool item questions were included in the validation. Their median age was 12 (IQR: 10-15) years, 2515 (46.7%) were male. HIV prevalence was 1.3% (95% CI:1.0-1.8%). The 4-item screening tool had poor accuracy with an area under the receiver operating curve of 0.65(95% CI: 0.60-0.72) at a cut-off score≥1. Its sensitivity was 56.3% (95% CI:44.0-68.1%) and specificity of 75.1% (95% CI:73.9-76.3%), PPV of 2.9% (95% CI:2.1-3.9%) and a NPV of 99.2% (95% CI:98.9-99.5%). The number needed to test to diagnose one child using the screening tool was 55% lower than universal testing for HIV.

CONCLUSION

Use of the 4-item screening tool could be a strategy that can be adopted to identify children living with HIV in a community setting in resource limited settings by reducing the number needed to test compared to universal testing since it is inexpensive, easy to administer and not harmful. However, screening items adapted to a community setting need to be explored to improve the performance of the screening tool.

Strategies for Identifying and Linking HIV-Infected Infants, Children, and Adolescents to HIV Treatment Services in Resource Limited Settings

Many children living with HIV in resource-limited settings remain undiagnosed and at risk for HIV-related mortality and morbidity. This article describes 5 key strategies for strengthening HIV case finding and linkage to treatment for infants, children, and adolescents. These strategies result from lessons learned during the Accelerating Children's HIV/AIDS Treatment Initiative, a public-private partnership between the President's Emergency Plan for AIDS Relief (PEPFAR) and the Children's Investment Fund Foundation (CIFF). The 5 strategies include (1) implementing a targeted mix of HIV case finding approaches (eg, provider-initiated testing and counseling within health facilities, optimization of early infant diagnosis, index family testing, and integration of HIV testing within key population and orphan and vulnerable children programs); (2) addressing the unique needs of adolescents; (3) collecting and using data for program improvement; (4) fostering a supportive political and community environment; and (5) investing in health system-strengthening activities. Continued advocacy and global investments are required to eliminate AIDS-related deaths among children and adolescents.

Scaling up Pediatric HIV Testing by Incorporating Provider-Initiated HIV Testing Into all Child Health Services in Hurungwe District, Zimbabwe

BACKGROUND

Practical ways are needed to scale-up pediatric HIV testing in sub-Saharan Africa, where testing is usually limited to HIV-exposed children in maternal and child health clinics.

METHODS

We implemented an enhanced pediatric HIV testing program in 33 health facilities in Zimbabwe by integrating HIV testing into all pediatric health services. We collected individual data on children tested by having health care workers complete a program-specific child health booklet. We compared numbers of children tested before and during the program using routinely collected aggregate program data reported by health facilities.

RESULTS

A total of 12,556 children aged 0-5 years were recorded in child health booklets; 9431 (75.1%) had information on HIV testing, of whom 7326 (77.7%) were tested; 7167 had test results of whom 122 (1.7%) were HIV-infected. Among children seen in outpatient clinics, 82.1% were tested compared with 66.5% tested among children seen in maternal/child health clinics. Of the 122 HIV-infected children identified, 77 (63.1%) could be missed under existing pediatric testing guidelines. The number of HIV-infected children identified during the 6-month program increased by 55% compared with the prior 6-month period (RR = 1.55, 95% CI: 1.22 to 1.96). Factors independently associated with HIV infection included being malnourished (adjusted odds ratio [AOR] = 7.7, 95% CI: 2.1 to 28.6), being exposed to TB (AOR = 8.1, 95% CI: 2.0 to 32.2), and having an HIV-infected mother (AOR = 41.6, 95% CI: 15.9 to 108.8).

CONCLUSIONS

Integrating HIV testing into all pediatric health services is feasible and can assist in identifying HIV-infected children who could be missed in current testing guidelines.

Clinical outcomes in children and adolescents initiating antiretroviral therapy in decentralized healthcare settings in Zimbabwe

INTRODUCTION

Decentralized HIV care for adults does not appear to compromise clinical outcomes. HIV care for children poses additional clinical and social complexities. We conducted a prospective cohort study to investigate clinical outcomes in children aged 6-15 years who registered for HIV care at seven primary healthcare clinics (PHCs) in Harare, Zimbabwe.

METHODS

Participants were recruited between January 2013 and December 2014 and followed for 18 months. Rates of and reasons for mortality, hospitalization and unscheduled PHC attendances were ascertained. Cox proportional modelling was used to determine the hazard of death, unscheduled attendances and hospitalization.

RESULTS

We recruited 385 participants, median age 11 years (IQR: 9-13) and 52% were female. The median CD4 count was 375 cells/mm3 (IQR: 215-599) and 77% commenced ART over the study period, with 64% of those who had viral load measured achieving an HIV viral load <400 copies/ml. At 18 months, 4% of those who started ART vs. 24% of those who remained ART-naïve were lost-to-follow-up (p < 0.001). Hospitalization and mortality rates were low (8.14/100 person-years (pyrs) and 2.86/100 pyrs, respectively). There was a high rate of unscheduled PHC attendances (34.94/100 pyrs), but only 7% resulted in hospitalization. Respiratory disease was the major cause of hospitalization, unscheduled attendances and death. CD4 count <350cells/mm3 was a risk factor for hospitalization (aHR 3.6 (95%CI 1.6-8.2)).

CONCLUSIONS

Despite only 64% of participants achieving virological suppression, clinical outcomes were good and high rates of retention in care were observed. This demonstrates that in an era moving towards differentiated care in addition to implementation of universal treatment, decentralized HIV care for children is achievable. Interventions to improve adherence in this age-group are urgently needed.

Community burden of undiagnosed HIV infection among adolescents in Zimbabwe following primary healthcare-based provider-initiated HIV testing and counselling: A cross-sectional survey

BACKGROUND

Children living with HIV who are not diagnosed in infancy often remain undiagnosed until they present with advanced disease. Provider-initiated testing and counselling (PITC) in health facilities is recommended for high-HIV-prevalence settings, but it is unclear whether this approach is sufficient to achieve universal coverage of HIV testing. We aimed to investigate the change in community burden of undiagnosed HIV infection among older children and adolescents following implementation of PITC in Harare, Zimbabwe.

METHODS AND FINDINGS

Over the course of 2 years (January 2013-January 2015), 7 primary health clinics (PHCs) in southwestern Harare implemented optimised, opt-out PITC for all attendees aged 6-15 years. In February 2015-December 2015, we conducted a representative cross-sectional survey of 8-17-year-olds living in the 7 communities served by the study PHCs, who would have had 2 years of exposure to PITC. Knowledge of HIV status was ascertained through a caregiver questionnaire, and anonymised HIV testing was carried out using oral mucosal transudate (OMT) tests. After 1 participant taking antiretroviral therapy was observed to have a false negative OMT result, from July 2015 urine samples were obtained from all participants providing OMTs and tested for antiretroviral drugs to confirm HIV status. Children who tested positive through PITC were identified from among survey participants using gender, birthdate, and location. Of 7,146 children in 4,251 eligible households, 5,486 (76.8%) children in 3,397 households agreed to participate in the survey, and 141 were HIV positive. HIV prevalence was 2.6% (95% CI 2.2%-3.1%), and over a third of participants with HIV were undiagnosed (37.7%; 95% CI 29.8%-46.2%). Similarly, among the subsample of 2,643 (48.2%) participants with a urine test result, 34.7% of those living with HIV were undiagnosed (95% CI 23.5%-47.9%). Based on extrapolation from the survey sample to the community, we estimated that PITC over 2 years identified between 18% and 42% of previously undiagnosed children in the community. The main limitation is that prevalence of undiagnosed HIV was defined using a combination of 3 measures (OMT, self-report, and urine test), none of which were perfect.

CONCLUSIONS

Facility-based approaches are inadequate in achieving universal coverage of HIV testing among older children and adolescents. Alternative, community-based approaches are required to meet the Joint United Nations Programme on HIV/AIDS (UNAIDS) target of diagnosing 90% of those living with HIV by 2020 in this age group.

A blood screening test for Alzheimer's disease

INTRODUCTION

This study combined data across four independent cohorts to examine the positive and negative predictive values of an Alzheimer's disease (AD) blood test if implemented in primary care.

METHODS

Blood samples from 1329 subjects from multiple independent, multiethnic, community-based, and clinic-based cohorts were analyzed. A "locked-down" referent group of 1128 samples was generated with 201 samples randomly selected for validation purposes. Random forest analyses were used to create the AD blood screen. Positive (PPV) and negative (NPV) predictive values were calculated.

RESULTS

In detecting AD, PPV was 0.81, and NPV was 0.95 while using the full AD blood test. When detecting mild cognitive impairment, PPV and NPV were 0.74 and 0.93, respectively. Preliminary analyses were conducted to detect any "neurodegenerative disease". The full 21-protein AD blood test yielded a PPV of 0.85 and NPV of 0.94.

DISCUSSION

The present study creates the first-ever multiethnic referent sample that spans community-based and clinic-based populations for implementation of an AD blood screen.