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

Risk Screening Tools Could Potentially Miss HIV-Positive Individuals Who Seek Testing Services: A Secondary Program Data Analysis on the Performance Characteristics of an Adolescent and Adult HIV Risk Screening Tool in Uganda

Improving HIV testing efficiency saves financial and material resources for health. We conducted a secondary data analysis of routinely collected HIV risk-screening program data in Uganda, from October to November 2019, to determine the performance characteristics of the adolescent and adult HIV risk screening tools in public health facilities. A total of 19,854 clients had been screened for HIV testing eligibility and tested for HIV. The overall positivity rate (cluster-weighted prevalence of HIV) among those screened was 4.5% (95% CI: 4.1-4.8) versus 3.71% (95% CI: 3.06-4.50) among those not screened. The sensitivity and specificity of the risk screening tool were 91% (95% CI: 89-93) and 25% (24.2-26), respectively. With screening, the number needed to test to identify one PLHIV was reduced from 27 to 22. Although risk screening would have led to a 24.5% (4825/19,704) reduction in testing volume, 9.3% (68/732) of PLHIV would have been missed and be misclassified as not eligible for testing. The cost saving per PLHIV identified was minimally reduced by 3% from USD 69 without screening to USD 66.9 with screening. Since the treatment-adjusted prevalence of HIV is dropping globally, overzealous use of risk screening tools to determine who to test or not carries the potential of missing PLHIV due to their limited specificity. We recommend the use of scientifically validated HIV risk screening tools, and a need to explore the use of HIV self-testing as a test for tirage to minimize misclassification of people who seek HIV testing services.

Optimizing HIV case identification: investigating client characteristics predictive of HIV positivity from provider-initiated testing (PITC) in central Kenya

BACKGROUND

Routine program data indicates positivity rates under 2% from HIV testing services (HTS) at sites supported by Centre for Health Solutions-Kenya in Central Kenya. Achieving the UNAIDS 95:95:95 goals requires continuous identification of people living with HIV in an environment of diminishing resources. We assessed non-clinical and clinical characteristics of persons who tested HIV-positive aimed at improving the process of HTS through Provider-Initiated HIV Testing & Counseling (PITC).

METHODS

We conducted a retrospective analysis of routine PITC program data collected between October 2018 and September 2019 from six health facilities located in three counties in central Kenya. Stratification was based on county and facility volume. A multivariable logistic regression model, clustered adjusted for facility using robust standard errors, was used to determine predictors of a positive HIV result.

RESULTS

The total sample was 80,693 with an overall positivity rate of 1.2%. Most, (65.5%), were female and 6.1% were < 15 years. Most clients, 55,464 (68.7%), had previously tested for HIV. Client characteristics associated with a higher odds of positivity on multivariable analysis included: being female (adjusted odds ratio [aOR] 1.27, 95% confidence interval [CI] (1.03-1.57); adults 15 years and above compared to children < 15 years, divorced and married polygamous compared to married monogamous [aOR 3.98, 95% CI (2.12-7.29) and aOR 2.41 95% CI (1.48-3.94) respectively]; clients testing for the first time compared to repeat testers in less than 12 months [aOR 1.39, 95% CI (1.27-1.51)]. Similarly, repeat testers in more than 12 months compared to repeat testers in less than 12 months [aOR 1.90, 95% CI (1.55-2.32)]; presumptive TB clients compared to those without signs of TB [aOR 16.25, 95% CI (10.63-24.84)]. Clients tested at inpatient departments (IPD) were more likely to get a positive HIV result compared to those tested at outpatient departments (OPD), and other departments.

CONCLUSIONS

The study findings highlight client characteristics such as age, marital status, HIV test entry point, first-time test, repeat test after 12 months, and TB status as factors that could influence PITC results and could be used to develop a screening tool to target eligible clients for HTS in low HIV prevalence settings.

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.

Improved access to HIV diagnosis and linkage to antiretroviral therapy among children in Southern Nigeria: a before-after study

BACKGROUND

Globally, two out of five children living with HIV (CLHIV) are unaware of their HIV status, and a little more than 50% are receiving antiretroviral therapy (ART). This paper describes case-finding strategies and their contribution to identifying CLHIV and linking them to ART in Nigeria.

METHODS

This before-after study used program data abstracted during the implementation of different paediatric-focused strategies (provider-initiated testing and counselling, orphans and vulnerable children testing, family-based index testing, early infant diagnosis (EID), community-driven EID, and community-based testing) delivered in health facilities and in communities to improve HIV case identification. Data were abstracted for children (0 to 14 years) who received HIV testing services and were initiated on ART in Akwa Ibom State, Nigeria during the pre-implementation period (April-June 2021) and during the implementation period (July-September 2021). Descriptive statistics were used to describe the testing coverage, positivity rate (proportion of tests that were positive for HIV), linkage to ART, and ART coverage, by age, sex, and testing modality. Interrupted time series analysis (ITSA) on STATA 14 was used to estimate the effect of the implementation of these strategies on HIV testing uptake and positivity rate at a 0.05 significance level.

RESULTS

A total of 70,210 children were tested for HIV within the six-month period, and 1,012 CLHIV were identified. A total of 78% (n = 54,821) of the tests and 83.4% (n = 844) CLHIV were diagnosed during the implementation period. During implementation, the HIV positivity rate increased from 1.09% (168/15,389) to 1.54% (844/54,821), while linkage to ART increased from 99.4% (167/168) to 99.8% (842/844). The contribution from community-based modalities to CLHIV identified increased from 63% (106/168) to 84% (709/844) during the implementation, with the majority, 60.8% (431/709), from community-based index testing. Overall, ART coverage increased from 39.7 to 55.6% at the end of the intervention period.

CONCLUSION

The findings show that expanding differentiated HIV testing approaches provided mostly in the community significantly increased pediatric case identification. However, ART coverage remains low, especially for younger age groups, and requires further efforts.

A machine learning model identifies patients in need of autoimmune disease testing using electronic health records

Systemic autoimmune rheumatic diseases (SARDs) can lead to irreversible damage if left untreated, yet these patients often endure long diagnostic journeys before being diagnosed and treated. Machine learning may help overcome the challenges of diagnosing SARDs and inform clinical decision-making. Here, we developed and tested a machine learning model to identify patients who should receive rheumatological evaluation for SARDs using longitudinal electronic health records of 161,584 individuals from two institutions. The model demonstrated high performance for predicting cases of autoantibody-tested individuals in a validation set, an external test set, and an independent cohort with a broader case definition. This approach identified more individuals for autoantibody testing compared with current clinical standards and a greater proportion of autoantibody carriers among those tested. Diagnoses of SARDs and other autoimmune conditions increased with higher model probabilities. The model detected a need for autoantibody testing and rheumatology encounters up to five years before the test date and assessment date, respectively. Altogether, these findings illustrate that the clinical manifestations of a diverse array of autoimmune conditions are detectable in electronic health records using machine learning, which may help systematize and accelerate autoimmune testing.

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.

Achieving HIV epidemic control through integrated community and facility-based strategies: Lessons learnt from ART-surge implementation in Akwa Ibom, Nigeria

This study examines the lessons learnt from the implementation of a surge program in Akwa Ibom State, Nigeria as part of the Strengthening Integrated Delivery of HIV/AIDS Services (SIDHAS) Project. In this analysis, we included all clients who received HIV counseling and testing services, tested HIV positive, and initiated ART in SIDHAS-supported local government areas (LGAs) from April 2017 to March 2021. We employed descriptive and inferential statistics to analyze our results. A total of 2,018,082 persons were tested for HIV. Out of those tested, 102,165 (5.1%) tested HIV-positive. Comparing the pre-surge and post-surge periods, we observed an increase in HIV testing from 490,450 to 2,018,082 (p≤0.031) and in HIV-positive individuals identified from 21,234 to 102,165 (p≤0.001) respectively. Of those newly identified positives during the surge, 98.26% (100,393/102,165) were linked to antiretroviral therapy compared to 99.24% (21,073/21,234) pre-surge. Retention improved from 83.3% to 92.3% (p<0.001), and viral suppression improved from 73.5% to 96.2% (p<0.001). A combination of community and facility-based interventions implemented during the surge was associated with the rapid increase in case finding, retention, and viral suppression; propelling the State towards HIV epidemic control. HIV programs should consider a combination of community and facility-based interventions in their programming.

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.

Optimising the adult HIV testing services screening tool to predict positivity yield in Zimbabwe, 2022

HIV positivity yield declined against increasing testing volumes in Zimbabwe, from 20% (1.65 million tests) in 2011 to 6% (3 million tests) in 2018. A screening tool was introduced to aid testers to identify clients likely to obtain a positive diagnosis of HIV. Consequently, testing volumes declined to 2.3 million in 2019 but positivity declined to 5% prompting the evaluation and validation of the tool to improve its precision in predicting positivity yield. A cross-sectional study was conducted. Sixty-four sites were randomly selected where all reporting clients (18+ years) were screened and tested for HIV. Participant responses and test outcomes were documented and uploaded to excel. Multivariable analysis was used to determine the performance of individual, combination questions and screening criteria to achieve >/ = 90% sensitivity for a new screening tool. We evaluated 13 questions among 7,825 participants and obtained 95.7% overall sensitivity, ranging from 3.9% [(95%CI:2.5,5.9) sharing sharp objects] to 86.8% [(95%CI:83.8,89.5) self-perception of risk] for individual questions. A 5-question tool was developed and validated among 2,116 participants. The best combination (self-perception of risk, partner tested positive, history of ill health, last tested >/ = 3months and symptoms of an STI) scored 94.1% (95%CI:89.4,97.1) sensitivity, 18% reduction in testing volumes and 11 Number Needed to Test (NNT). A screening in criteria that combine previously testing >/ = 3 months with a yes to any of the 4 remaining questions was analysed and sensitivity ranged from 89.9% (95%CI:84.4,94.0) for last tested >/ = 3months and sexual partner positive, to 93.5% (95%CI:88.7,96.7) for last tested >/ = 3months and self-perceived risk We successfully developed, evaluated and validated an HIV screening tool. High sensitivity and the fifth reduction in testing volume were acceptable attributes to enhance testing efficiency and effective limited resource utilisation. Screened out clients will be identified through frequent screening and self-testing options.