Work

Real-world multicountry programmatic assessment of contact investigation for people with drug-resistant tuberculosis: evidence from five high-burden countries

Year: 2026

Type: article

Abstract: Introduction Contact investigation (CI) is a key strategy for ensuring tuberculosis (TB) diagnosis and prompt treatment initiation. However, its implementation remains limited, particularly for people with drug-resistant TB (DR-TB). This study summarises the approaches and presents yield cascades for DR-TB CI initiatives from five high-burden countries.Methods CIs were implemented via the Stop TB Partnership’s TB REACH Wave 9 funding cycle in Bangladesh, Ethiopia, Pakistan, Nigeria and Vietnam. Narrative data were thematically synthesised to identify shared and context-specific implementation strategies. Quantitative data included the number of index individuals with DR-TB, contacts screened and tested and TB diagnoses by drug resistance. Results were compared across countries.Results Three CI strategies were used: (1) symptom screening (Bangladesh, Ethiopia, Nigeria), (2) parallel symptom and chest X-ray screening (Pakistan) and (3) universal molecular testing (Vietnam). These were applied in diverse settings, including nomadic, displaced and urban populations. All sites conducted CI for people newly starting DR-TB treatment but CIs were also performed for historical cohorts of people with DR-TB in some contexts. A total of 3919 people with DR-TB were eligible for CI, and CI coverage was 95.2% (n=3732). A total of 11 184 household contacts were enumerated (average of 3.0 contacts per CI), and 10 901 (97.5%) were screened. 194 people were diagnosed with TB, of whom 165 (85.1%) were bacteriologically confirmed and 89 (53.9%) had rifampicin resistance. Drug-susceptible TB and DR-TB detection rates among DR-TB contacts were 1.5% (range 0.14–3.9%) and 0.8% (range 0–3.3%), respectively.Conclusion CI outcomes for DR-TB varied across settings. These findings support the scale-up of context-adapted CI to improve DR-TB detection and care. Scaling context-specific CI, linked with contact screening, diagnostic evaluation and preventive treatment, will be critical to disrupt DR-TB transmission and achieve End TB targets.

Source: BMJ Global Health

DOI: 10.1136/bmjgh-2025-021870