RESUMEN
INTRODUCTION: In line with the WHO recommendation, Nepal has started implementing Tuberculosis prevention therapy (TBPT) for under five children exposed to Sputum Smear Positive Pulmonary Tuberculosis, as one of the strategies for prevention, care and control of TB. Implementation fidelity study is important to assess on what extent preventive program is being implemented. The objective of the study measured the implementation fidelity of TBPT program Kaski district, Nepal. METHODS: We used a mixed-method explanatory sequential design study. Quantitative data were collected through retrospective review of records from April 2018 to May 2019 and level of adherence was established. Moderating factors influencing the implementation of TBPT were TBPT were assessed qualitatively. Sixteen in-depth interviews and a focus group discussion was conducted purposively with responsible stakeholders. The study was guided by the Conceptual Framework for Implementation Fidelity (CFIR) developed by Carroll. RESULTS: The majority of the components of the TBPT program were found to be implemented with a moderate level of fidelity. The proportion of under five years children initiate and complete the full course of TBPT was 72.5% and 75.86% respectively. The proportion of index cases traced for household contact, contact tracing within two months and timely initiation of therapy within two months were 54.19%, 82.73% and 86.20%. Moderating factors identified in the implementation of the program were contact tracing and enrollment, partnership and ownership, training resources, medication, awareness and information dissemination. CONCLUSION: The TBPT program is being moderately implemented in Kaski districts. Addressing the key challenges identified in contact tracing, partnership/ownership, incentives, training and knowledge of health workers results in more identification of children eligible for TBPT.