Implementation of isoniazid preventive therapy among children living with diagnosed pulmonary tuberculosis patients: A mixed methods study from Mumbai, India

Background: Tuberculosis remains a significant public health issue, particularly among children who are in close contact with tuberculosis patients. India accounts for a large proportion of global tuberculosis cases. Despite global recommendations for Isoniazid Preventive Therapy to prevent latent tuberculosis infection from progressing to active disease, the initiation and adherence to Isoniazid Preventive Therapy remain suboptimal, especially in high-burden settings. Understanding the barriers to Isoniazid Preventive Therapy implementation is crucial to improving treatment outcomes and achieving tuberculosis elimination goals.

Objectives: This study aimed to quantify the uptake of isoniazid among children under 6 years who were started on Isoniazid Preventive Therapy and to identify the challenges from the perspectives of caregivers and healthcare providers.

Methods: The study was conducted in a slum in Mumbai, India, from June to December 2023, using a mixed-methods design. The quantitative phase involved a house-to-house survey, covering all 96 contacts started on Isoniazid Preventive Therapy in 2022, using a semi-structured questionnaire. The qualitative phase included key informant interviews with healthcare providers and in-depth interviews with caregivers. Quantitative data were analysed using Fisher's exact test and chi-square test, while qualitative data were analysed thematically.

Results: Of the 96 children, 11 (11.45%) completed therapy, with an average treatment duration of 2.5 months. Quantitative findings highlighted fear of side effects and family migration as major reasons for discontinuation. Completion of chemoprophylaxis was significantly associated with factors like male gender, support from extended family, home visits by tuberculosis health staff, and shorter travel time (under 30 min) to the tuberculosis unit. Qualitative data revealed challenges across themes of supply, staff, training, services, and adherence. Key challenges included lack of awareness, unavailability of isoniazid in syrup form, inadequate training for health workers, weak program monitoring, insufficient staffing, and fears related to tuberculosis exposure during outpatient department visits.

Conclusion: Effective counselling, regular follow-ups, availability of medications in syrup form, increasing staffing based on case burden, timely training of staff, strengthening program monitoring, and ensuring infection control in tuberculosis outpatient departments are critical to achieving successful completion of isoniazid preventive therapy.