OA-31-690-23 Methods and challenges of National TB Prevalence Surveys in Asia and sub-Saharan Africa: a systematic review

Background and challenges to implementation: Nation- al TB Prevalence Surveys (TBPS) provide valuable in- formation to policy makers and National TB Programs about TB burden and missing cases. However, TBPS can be challenging, especially in TB-endemic low- and middle-income countries (LMICs). Intervention or response: We reviewed 28 World Health Organisation (WHO) TBPS reports from Asia (n=14) and sub-Saharan Africa (n=14), published after 2000. All surveys were population based and followed WHO guidance. All surveys used a TB symptom screening questionnaire and chest radiograph to identify people with suspected TB disease. Acid Fast Bacilli (AFB) smear (25/28, 89%), fluorescence microscopy (17/28, 61%), and mycobacterial culture (27/28, 96%) were used to diagnosed TB, with most post-2010 surveys also using GeneXpert (14/28, 50%). Results/Impact: Several domains of TBPS challenges were identified and are summarized in Table 1. They included: 1) under-recruitment in urban settings (4/28, 14%) and exclusion of children and people with extrapulmonary or clinically-diagnosed TB (28/28, 100%); 2) under-representation of risk groups due to lack of complementary data collection concerning social deter- minants and reliance on self-reporting of TB risk factors including HIV and diabetes (28/28, 100%); 3) diagnostic limitations including reliance on low-sen- sitivity smear testing (14/28, 50%) and impaired labora- tory capacity; 4) logistical implementation constraints including lack of funding and security issues; and, 5) issues with data management, especially with paper- based data collection (4/28, 14%). Conclusions: Asian and African LMICs planning to con- duct TBPS should focus on addressing potential modi- fiable challenges including: garnering adequate fund- ing and promoting a sustainable workforce; developing context- and resource-specific diagnostic algorithms to improve TB yield; social mobilization and awareness campaigns to improve participation, including of hard- to-reach groups; expanding inclusion criteria to children and non-microbiologically confirmed TB cases; better linkage with socioeconomic and health data; and paper- less data collection and management tools