WHO operational handbook on tuberculosis: module 3: diagnosis: rapid diagnostics for tuberculosis detection, 2021 update

Overview

The “WHO operational handbook on tuberculosis. Module 3: Diagnosis - Rapid diagnostics for tuberculosis detection 2021 update” is the latest document replacing the one issued in 2020. Three new nucleic acid amplification test (NAAT) classes are endorsed by WHO and included in the “WHO consolidated guidelines on tuberculosis. Module 3: Diagnosis - Rapid diagnostics for tuberculosis detection 2021 update.”

The latest operational handbook includes the new classes recommended by WHO. It aims at facilitating the implementation of the WHO recommendations by the Member States, technical partners, and others involved in managing patients with TB and DR-TB. The operational handbook provides practical information on existing and new tests recommended by WHO, step-by-step advice on implementing and scale-up testing to achieve local and national impact and lastly, model diagnostic algorithms, which are updated to incorporate the latest recommendations. An overview of budgetary considerations and information sheets on each of the newly recommended tests is provided.

The three new classes of technologies included in the update are: (1) the moderate complexity automated NAATs, recommended for the initial detection of TB and resistance to rifampicin and isoniazid, providing more options for early diagnosis of TB and rifampicin-resistant TB but also addressing an important gap in the rapid diagnosis of isoniazid-resistant and rifampicin-susceptible TB; (2) the low complexity automated NAATs, recommended for the detection of resistance to isoniazid and second-line anti-TB agents, which will improve access to testing of fluoroquinolones resistance at peripheral level; and (3) the high complexity reverse hybridization-based NAATs, recommended for the detection of pyrazinamide resistance, representing the first molecular tests for resistance determination to this drug.