The decision to test an individual for TB infection implies an intention to offer TPT. TB infection testing should therefore be reserved for populations in whom the risk of developing TB disease is high and who will benefit the most from TPT. Decisions to start TPT should always consider risk of adverse drug events, in addition to TB symptoms and the TB infection test result. Box 2.1 summarizes the groups WHO recommends should receive TPT, with testing not mandatory for groups 1–3. More detail can be found in Module 1 of the WHO operational handbook on TB (1).