Prevalence of latent tuberculosis infection in Syrian refugees to Canada.

Abstract

Canada has accepted more than 25,000 Syrian refugees fearing persecution in their homeland. Canadian guidelines recommend screening recent refugees from high incidence countries for tuberculosis (TB) and latent TB infection (LTBI). The prevalence of TB in this population is unknown. A refugee clinic in Edmonton presented a unique opportunity to estimate prevalence of TB and LTBI in Syrian refugees arriving in Canada. In January 2016, 100 consecutive Syrian refugees were screened for TB with clinical assessment and LTBI using QuantiFERON Gold In-Tube assay (QFT-GIT). Patients with positive QFT-GIT were referred to Edmonton Tuberculosis Clinic (ETBC) for evaluation and, if appropriate, offered prophylaxis. No cases of active TB were found. Valid QFT-GIT were measured in 99 of 100 individuals and of these,nine (9%) were positive using a threshold concentration of blood interferon-γ greater than 0.35IU/L. Eight of thenine patients attended follow-up appointments; of these,seven began LTBI prophylaxis and all seven (78%) completed same. The 9% (95% confidence interval 3-15%) prevalence of LTBI was higher than expected in this population.