Home-
Contact investigation and follow-up is an essential component of tuberculosis (TB) programs in Canada, and of the World Health Organization (WHO) framework for TB elimination in low-burden countries.
-
Only pulmonary and laryngeal TB are infectious, with limited exceptions. Contact investigation should be prioritized according to the infectiousness of the source case, extent of exposure and immunologic vulnerability of those exposed; contact investigation should be carried out for both sputum smear-negative and smear-positive cases. Contact investigation is iterative: it should be expanded if initial results indicate that transmission has occurred.
-
The objective of contact investigation is to rapidly identify and treat any secondary cases, and to identify contacts with latent TB infection (LTBI) in order to offer preventive treatment. Source-case investigation (“reverse contact investigation”) should be done for children under 5 years old with TB disease.
-
Household members are consistently at highest risk, even when the index patient has smear-negative disease. In theory, there is no amount of exposure to infectious TB that is absolutely without risk; in practice, almost all transmission occurs with close, prolonged or repeated contact over days or months.
-
Clinical assessment, TB screening and follow-up of contacts should follow standard practices; and TB programs should have clearly identified clinical referral pathways.
Switch To: Français