Canadian Journal of Public Health

, Volume 109, Issue 1, pp 8–14 | Cite as

Prevalence of latent tuberculosis infection in Syrian refugees to Canada

  • Peter Warrington
  • Gregory Tyrrell
  • Kimberley Choy
  • Lisa Eisenbeis
  • Richard Long
  • Ryan Cooper
Quantitative Research
  • 27 Downloads

Abstract

Objectives

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.

Methods

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.

Results

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 0.35 IU/L. Eight of the nine patients attended follow-up appointments; of these, seven began LTBI prophylaxis and all seven (78%) completed same.

Conclusion

The 9% (95% confidence interval 3–15%) prevalence of LTBI was higher than expected in this population.

Keywords

Latent tuberculosis Tuberculosis Refugees Syria 

Résumé

Objectifs

Le Canada a accepté plus de 25 000 réfugiés syriens fuyant la persécution dans leur patrie. Les lignes directrices canadiennes recommandent le dépistage de la tuberculose et de la tuberculose-infection latente (TBIL) chez les réfugiés récents des pays à forte incidence. La prévalence de la tuberculose dans cette population est inconnue. Une clinique pour les réfugiés d’Edmonton a représenté une occasion unique d’estimer la prévalence de la tuberculose et de la TBIL chez les réfugiés syriens arrivant au Canada.

Méthode

En janvier 2016, 100 réfugiés syriens de suite ont subi des tests de dépistage de la tuberculose avec évaluation clinique et de dépistage de la TBIL à l’aide du test QuantiFERON Gold In-Tube Assay (QFT-GIT). Les patients séropositifs selon le QFT-GIT ont subi une évaluation à la clinique de tuberculose d’Edmonton (ETBC) et, le cas échéant, se sont fait offrir une prophylaxie.

Résultats

Aucun cas de tuberculose active n’a été décelé. Des épreuves QFT-GIT valides ont été réalisées chez 99 personnes sur 100, et neuf d’entre elles (9 %) ont affiché des résultats positifs, soit un seuil de concentration supérieur à 0,35 UI/l selon le test sanguin interféron gamma. Huit patients sur neuf se sont présentés aux rendez-vous de suivi, sept ont commencé un traitement contre la TBIL en prophylaxie, et tous les sept (78 %) l’ont terminé.

Conclusion

La prévalence de 9 % (intervalle de confiance de 95 %: 3–15 %) de la TBIL était plus élevée que prévu dans cette population.

Mots-clés

Tuberculose latente Tuberculose Réfugiés Syrie 

Notes

Compliance with ethical standards

Ethics approval was provided by the University of Alberta Research Ethics Board.

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© The Canadian Public Health Association 2018

Authors and Affiliations

  • Peter Warrington
    • 1
  • Gregory Tyrrell
    • 2
    • 3
  • Kimberley Choy
    • 4
  • Lisa Eisenbeis
    • 5
  • Richard Long
    • 1
    • 6
  • Ryan Cooper
    • 1
  1. 1.Faculty of Medicine and DentistryUniversity of AlbertaEdmontonCanada
  2. 2.Department of Laboratory Medicine and PathologyUniversity of AlbertaEdmontonCanada
  3. 3.Provincial Laboratory for Public HealthAlberta Health ServicesEdmontonCanada
  4. 4.Public HealthAlberta Health ServicesEdmontonCanada
  5. 5.Edmonton Tuberculosis ClinicAlberta Health ServicesEdmontonCanada
  6. 6.School of Public HealthUniversity of AlbertaEdmontonCanada

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