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

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.

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.