Background: South Africa has one the highest TB and HIV burdens globally. TB preventive therapy (TPT) reduces the risk of TB disease and TB-related mortality in adults and children living with HIV and is indicated for use in TB-exposed HIV-negative individuals and children. TPT implementation in South Africa remains suboptimal.

Methods: We conducted a pragmatic review of TPT implementation using multiple data sources, including informant interviews (n = 134), semi-structured observations (n = 93) and TB patient folder reviews in 31 health facilities purposively selected across three high TB burden provinces. We used case descriptive analysis and thematic coding to identify barriers and facilitators to TPT implementation.

Results: TPT programme implementation was suboptimal, with inadequate monitoring even in health districts with well-functioning TB services. Health workers reported scepticism about TPT effectiveness, deprioritised TPT in practice and expressed divergent opinions about the cadres of staff responsible for implementation. Service- and facility-level barriers included ineffective contact tracing, resource shortages, lack of standardised reporting mechanisms and insufficient patient education on TPT. Patient-level barriers included socio-economic factors.

Conclusions: Improving TPT implementation will require radically simplified and more feasible systems and training for all cadres of health workers. Partnership with communities to stimulate demand driven service uptake can potentially facilitate implementation.