neutral

Either a tuberculin skin test (TST) or interferon-gamma release assay (IGRA) can be used to
test for LTBI.

Three times weekly dosing throughout therapy [2(HRZE)3/4(HR)3] may be
used as another alternative to Recommendation 2.1, provided that every
dose is directly observed and the patient is NOT living with HIV or living in
an HIV-prevalent setting.

If a daily continuation phase is not possible for these patients, three times
weekly dosing during the continuation phase is an acceptable alternative.

Priority should be given to achieving adequate ACH using ventilation systems. However, in some settings it is not possible
to achieve adequate ventilation; for example, because of climatic changes (e.g. in winter or during the night) or building
structure, or because transmission of TB would pose a high risk of morbidity and mortality (e.g. in MDR-TB wards). In such
cases, a complementary option is to use upper room or shielded ultraviolet germicidal irradiation (UVGI) devices. This environmental control does not provide fresh air or directional airflow.

In populations with known or suspected high levels of isoniazid resistance, new
TB patients may receive HRE as therapy in the continuation phase as an acceptable alternative to HR.