Table 13– Organisation and timing of evaluation of contacts of infectious tuberculosis patients
Contact groupTiming
<1 week after diagnosis (or as soon as possible)After window period (8 weeks after last contact with the index case during the period of infectiousness)
High-priority
 Vulnerable close contacts and contacts with symptoms of tuberculosisTST#/IGRA and chest radiographTST/IGRA and chest radiography
 Other close contactsOptional or when proved transmission among (vulnerable) close contacts: TST#/IGRA and chest radiographTST/IGRA
Medium-priority
 Vulnerable casual contactsWhen proved transmission among high priority contacts: TST#/IGRA and chest radiographTST/IGRA
 Other medium priority contactsWhen proved transmission among high priority contacts: TST/IGRA
Low-priorityWhen proved considerable transmission among medium priority contacts: TST/IGRA
  • TST: tuberculin skin test; IGRA: interferon-γ release assay. #: when there is a history of a previous positive tuberculin skin test, tuberculosis or latent infection with M. tuberculosis, no tuberculin skin test should be administered; : in bacille Calmette–Guérin-vaccinated patients, it is recommended not to use the tuberculin skin test in the first round of examination to avoid boosting in the second round.