IMPACT OF THE USE OF THE ULTRA-PORTABLE DIGITAL X-RAY WITH CAD4TB FOR ACTIVE CASE FINDING FOR TUBERCULOSIS IN NIGERIA

Abiola Alege¹Sani Useni²Austin Ihesie³Rupert Eneogu³Aderonke Agbaje⁴Bethrand Odume²Debby Nongo³Eze Chukwu²Chidubem Ogbudebe²Omosalewa Oyelaran³Chris Anyomi⁵Samuel Akingbesote⁴Zhi Zhen Qin⁶Rachael Barrett⁶Obioma Chijioke-Akaniro⁷Chukwuma Anyaike⁷Atana Uket Ewa^8,9*

• ¹Society for Family Health Nigeria, Lagos, Nigeria
• ²KNCV Nigeria, Abuja, Nigeria
• ³United States Agency for International Development (Nigeria), Abuja, Nigeria
• ⁴Institute of Human Virology, Abuja, Nigeria
• ⁵Centre for Integrated Health Programs, Abuja, Nigeria
• ⁶Stop TB Partnership, Geneva, Switzerland
• ⁷Federal Ministry of Health, Abuja, Nigeria
• ⁸University of Calabar, Calabar, Nigeria
• ⁹University of Calabar Teaching Hospital, Calabar, Nigeria

The Ultra-portable-digital-Xray (UPDX) with Computer-Aided-Detection (CAD4TB) is a new technology aimed at bringing tuberculosis (TB) screening innovations to hardto-reach communities and strengthen the active case finding (ACF) interventions for TB. As TB control measures remain critical globally and in Nigeria, the country acquired and rolled out 10 UPDX with CAD in 8 states. This study seeks to evaluate the efficiency and impact of the UPDX with CAD4TB for TB case finding in Nigeria.A retrospective cross-sectional study involving the review of records of individuals 4 years and above who had presented for TB screening during ACF activities conducted using the UPDX with CAD4TB between January 2022 and September 2022.Results: A total of 94,694 subjects 4 years and above were screened for TB with an average presumptive TB proportion of 10.84±5.42% and 10% confirmed TB (r=0.684, p=0.03 and r(df) = r 0.867, p=0.001). The Number needed to screen (NNS) to find one TB case in Northern Nigeria was 39 as against an NNS for the South of 37 (x 2 = 108, p=0.25) and correlations (r = -0.422, p=0.17 and r(df) = -0.575, p=0.05). Similarly, a comparison of the number-needed-to-test (NNT) to find one TB case in Northern and Southern Nigeria gave a North total of 4 against a South total of 5 (x 2 = 60, p=0.3), with correlations (r= -0.033, p=0.92 and r(df) = -0.212, p=0.51) respectively.Among the TB cases confirmed, 3.4 % were asymptomatic with cough and fever absent in 18.2% and 83.2% respectively. The average time-to-diagnosis (TTD) was 2.0 ± 1.04 days while the average time-to-treatment (TTT) was 4.2 ± 1.14 days, with 50.6% receiving same day diagnosis, and 34.5%, same day treatment. The cumulative risks of radiation exposure on healthcare workers using UPDX with CAD4TB and adhering to personal protective practices, were found to be low.We documented the usefulness of UPDX with CAD showing a high TB prevalence and test positivity rate, with significant burden of subclinical TB. This has highlighted the need to scale up its use for ACF for TB and select CAD thresholds for both children and adults.