Table 1 Definitions of cases, contacts, intervention and comparator arms

TB case

A definite TB case is defined as an individual with newly diagnosed smear-positive or culture positive TB. Smear-negative individuals meeting NTP clinical guidelines for TB (cough >14 days duration with or without the presence of chest pain, fever, haemoptysis (blood in sputum), night sweats or fatigue and/or weight loss) [33, 40] were classified as probable cases.

Household Contact

Household contact is defined as living and sleeping at the same dwelling/property as the respective index case at the time of diagnosis, sharing kitchen and bathroom facilities [28, 33, 41].

Routine practice comparator

Passive case finding is the current NTP DOTS program of symptomatic persons voluntarily self-reporting to the health system for diagnosis of TB and initiation of chemotherapy [42]. Newly diagnosed and retreated smear positive TB cases enrolled in DOTS treatment at SJL NTP clinics are asked to name their HCs and encouraged to tell household members ≥15 years with cough >14 days to self-report to the clinic for evaluation. All children <15, with or without symptoms, are encouraged to attend clinic for evaluation for latent or active TB (as per DISA NTP guidelines). TB evaluation at clinics includes sputum smear microscopy, chest x-ray and clinical evaluation.

Intervention – active case finding of HCs – Familia Saludables de contactos de TB Program (Fig. 2)

The DISA NTP proposes the Familia Saludables de contactos de TB program which includes households visits of all newly diagnosed TB cases enrolled in DOTS treatment within a DISA NTP clinic. During the home visit NTP staff evaluates all HCs for symptoms of active TB. Any person reporting cough for >14 days are asked to provide a spot sputum for microscopy and referred to the clinic for chest x-ray and clinical evaluation. All HCs ≤15 years are referred to the health centre for chest x-ray, pediatric clinical evaluation and initiation of treatment for active or latent TB as required. Counseling including TB infection control practices and importance of diagnosis and treatment completion for TB cases is provided to household members. The ACF home visit is to be repeated at three times, within a month of the time the index TB case initiates treatment, at 3 months and at 6 months.