WHO updates guidelines on TB prevention and treatment

World Health Organization has updated its guidelines on tuberculosis preventive treatment.

The new guidance shall help countries speed up efforts to stop people with tuberculosis (TB) infection becoming sick with TB by giving them preventive treatment.

A large number of people are estimated to be infected with TB bacteria but they are neither sick nor contagious. They are; however, at greater risk of developing TB disease. Providing TB preventive treatment to these people will protect them from becoming sick and will decrease the risk of transmission in the community.

WHO has recommended a scale-up of TB preventive treatment among populations at highest risk including household contacts of TB patients, people living with HIV and other people at risk with weakened immunity or living in crowded settings. It also recommends an integration of TB preventive treatment services into ongoing case finding efforts for active TB. Either a tuberculin skin test or interferon-gamma release assay (IGRA) has been recommended to test for TB infection.

The new consolidated guidelines recommend a range of innovative approaches to scale up access to TB preventive treatment:

1.WHO recommends a scale-up of TB preventive treatment among populations at highest risk including household contacts of TB patients, people living with HIV and other people at risk with lowered" immunity or living in crowded settings.

2.WHO recommends an integration of TB preventive treatment services into ongoing case finding efforts for active TB. All household contacts of TB patients and people living with HIV are recommended to be screened for active TB. If active TB is ruled out, they should be initiated on TB preventive treatment.

3.WHO recommends that either a tuberculin skin test or interferon-gamma release assay (IGRA) be used to test for TB infection. Both tests are helpful to find people more likely to benefit from TB preventive treatment but should not become a barrier to scale-up access. Testing for TB infection is not required before starting TB preventive treatment in people living with HIV, and children under 5 years who are contacts of people with active TB.

4.WHO recommends new shorter options for preventive treatment in addition to the widely used 6 months of daily isoniazid. The shorter options that are now recommended range from a 1 month daily regimen of rifapentine plus isoniazid to 3 months weekly rifapentine plus isoniazid, 3 months daily rifampicin plus isoniazid, or 4 months of daily rifampicin alone.

The 18 recommendations on tuberculosis preventive treatment in the 2020 update cover critical steps in programmatic management that follow the cascade of preventive care. The main changes introduced include conditional recommendations for a 1-month daily rifapentine and isoniazid regimen and a 4-month daily rifampicin regimen as alternative treatment options in all TB burden settings. Advice on isoniazid preventive treatment in pregnancy and on the concomitant use of rifapentine and dolutegravir has been updated to reflect the findings from latest studies. The operational limitations that need to be overcome by countries to achieve global targets are highlighted and will be discussed in greater detail in the accompanying operational handbook that is being released concurrently. The guidelines are to be used primarily in national TB and HIV programmes, or their equivalents in ministries of health, and for other policy-makers working on TB and HIV and infectious diseases in public and private sectors and in the community.

Among the new recommendations, the group conditionally recommends shorter regimens as alternative treatment options: 1 month of daily rifapentine and isoniazid, or 4 months of daily rifampicin.