Chapter 11: Tuberculosis contact investigation and outbreak management

Figures & data

Figure 1. Timelines for contact investigation.

Figure 2. Evaluating exposure risk: Time, proximity, characteristics of the shared air space.

Figure 3. Scope of initial contact investigation.

Table

	Prevalence of LTBI (%)	Type of test	Publication year
Close contacts born in Canada/US ^20	31.0	TST (≥5 mm)	2020
Close contacts born outside Canada/US ^20	75.6	TST (≥5 mm)	2020
First Nations schoolchildren on reserve, routine school screening (at low risk of TB exposure) ^119	BCG in infancy 5.7 no BCG 0.2	TST (≥10 mm)	2011
Kindergarten children, routine school screening, Iqaluit, Nunavut ^120	11.4	TST (≥10 mm)	2019
Government-assisted refugees ^121	36.0	TST (≥10 mm)	2016
Refugees, medium-incidence origin (about 20/100,000) ^122	9.0	IGRA	2018
Migrant children, school-based screening ^123	22.8	TST (≥10 mm)	2010
Refugees, very high-incidence origin (>300/100,000) ^124	51.0	IGRA	2016
Federal inmates ^125	17.6	TST (≥10 mm)	2008
Dialysis patients, routine screening ^126	11.5	IGRA	2020
Hematologic cancer patients, routine screening ^127	8.2	TST (≥10 mm)	2020

Abbreviations: LTBI, latent tuberculosis infection; TST, tuberculin skin tests; TB, tuberculosis; BCG, Bacille Calmette-Guerin; IGRA interferon-gamma release assay

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