WHO consolidated guidelines on tuberculosis. Module 1: prevention - tuberculosis preventive treatment, second edition

Key points

• The second edition (2024) has 21 recommendations covering the full cascade of TB preventive treatment (TPT): identifying risk groups, ruling out TB disease, testing for TB infection and choosing a regimen.
• Adults and adolescents with HIV who are unlikely to have TB disease should receive TPT as part of HIV care, even if testing for TB infection is unavailable.
• Household contacts under 5 years of people with bacteriologically confirmed pulmonary TB should be given TPT once TB disease is excluded; older children, adolescents and adults may be given TPT.
• New: contacts exposed to multidrug- or rifampicin-resistant TB (MDR/RR-TB) should receive 6 months of daily levofloxacin.
• Recommended regimens regardless of HIV status: 6 or 9 months of daily isoniazid, 3 months of weekly rifapentine plus isoniazid, or 3 months of daily isoniazid plus rifampicin.

Overview

This WHO guideline sets out who should receive TB preventive treatment, how to rule out TB disease first, how to test for TB infection and which regimens to use. It supersedes the 2020 edition; most recommendations are largely unchanged, and the main change is 6 months of daily levofloxacin as TPT for people exposed to MDR/RR-TB in all settings, subject to certain conditions. About one fourth of the world's population is estimated to have been infected with M. tuberculosis, and on average 5-10% of infected people develop TB disease during their lives, usually within the first 5 years. Current TPT regimens have an efficacy of 60% to 90%. This overview is based on the guideline's executive summary and introduction.

Who should receive TPT

People with HIV: adults and adolescents unlikely to have TB disease should receive TPT, including those on antiretroviral treatment, pregnant women and people previously treated for TB, irrespective of the degree of immunosuppression. Infants under 12 months with HIV who are in contact with a person with TB should receive TPT, and children aged 12 months and older with HIV should be offered it in settings with high TB transmission, regardless of contact. Children with HIV who have completed TB treatment may receive TPT.

Other risk groups: people starting anti-tumour-necrosis factor treatment, receiving dialysis, preparing for an organ or haematological transplant or with silicosis should be systematically tested and treated for TB infection. This may be considered for prisoners, health workers, immigrants from countries with a high TB burden, homeless people and people who use drugs.

Ruling out TB disease

Adults and adolescents with HIV should be screened with a clinical algorithm: those without current cough, fever, weight loss or night sweats are unlikely to have TB disease. Chest X-ray, C-reactive protein with a cut-off above 5 mg/L or molecular WHO-recommended rapid diagnostic tests may also be used. In HIV-negative household contacts aged 5 years and older and other risk groups, the absence of TB symptoms and of abnormal chest radiographic findings may be used to rule out TB disease. Close contacts under 15 years should be screened for cough, fever or poor weight gain, with chest radiography, or both.

Testing for TB infection and regimens

Either a tuberculin skin test (TST) or an interferon-gamma release assay (IGRA) can be used, and the newer Mycobacterium tuberculosis antigen-based skin tests (TBST) may be used. Alternative regimens that may be used regardless of HIV status are 1 month of daily rifapentine plus isoniazid or 4 months of daily rifampicin. The dosage table has moved to the WHO operational handbook on TPT.

What changed from 2020

Two recommendations were withdrawn: one against systematic testing and treatment of TB infection in people with diabetes, people who use alcohol, tobacco smokers and underweight people, and one on 36 months of isoniazid for people with HIV in high-transmission settings. Recommendations on new screening tools and on screening contacts and other risk groups were added from the 2021 WHO TB screening guidelines, and the regimen recommendation was split into strongly and conditionally recommended options.

FAQ

Is a TB infection test required before preventive treatment?

Not always. Testing is desirable whenever feasible, but adults and adolescents with HIV and household contacts under 5 years should receive TPT even if testing for TB infection is unavailable.

What is recommended for contacts of people with MDR/RR-TB?

6 months of daily levofloxacin should be used as TB preventive treatment. This is the main new recommendation of the second edition.

Which tools can help rule out TB disease in people with HIV before TPT?

A symptom screen for current cough, fever, weight loss or night sweats, plus chest X-ray, C-reactive protein above 5 mg/L or molecular WHO-recommended rapid diagnostic tests.

Source

World Health Organization. WHO consolidated guidelines on tuberculosis. Module 1: prevention - tuberculosis preventive treatment, second edition. Geneva: World Health Organization; 2024. ISBN: 978-92-4-009619-6. Open access under CC BY-NC-SA 3.0 IGO. Summary prepared by Medpresso from the original publication; it is not a substitute for the full text or for medical advice.