Abstract
Inuit in the Arctic are experiencing an increase in tuberculosis cases, reaching levels in Greenland comparable to high-incidence countries. This prompted us to study the level of tuberculosis transmission to Greenlandic children. Specifically, we estimated the current prevalence of Mycobacterium tuberculosis infection (MTI) and the underlying annual risk of MTI.
2,231 Greenlandic school children aged 5–17 yrs (∼25% of the Greenlandic population in the relevant age group) were tested for MTI using the tuberculin skin test and the QuantiFERON®-TB Gold in-tube test. Subjects with dual-positive results were considered infected and subjects with dual-negative results uninfected. The children with discordant test results were classified as probably having MTI and analysed separately.
8.1% of the children had dual-positive test results. The annual risk of MTI was estimated as 0.80% (95% CI 0.67–0.92%) giving a cumulative risk at the 18th birthday of 13.4%. The annual risk of MTI varied substantially by ethnicity (0.87% in Inuit children, 0.02% in non-Inuit children; p<0.001) and by location (0.13% on the west coast, 1.68% on the south coast; p<0.001).
M. tuberculosis transmission occurs at a very high level in Inuit children with pronounced geographic differences emphasising the need for immediate public health interventions.
Footnotes
Support Statement
The study was funded by The Commission for Scientific Research in Greenland (Nuuk, Greenland), the Danish Research Council, the Greenlandic Home Rule Government, Cluster in International Health, Faculty of Health Sciences, University of Copenhagen, the Danish Lung Association, the Thorvald Madsen Foundation, Fonden til Lægevidenskabens fremme, the Ebba Celinder Foundation. The sponsor played no role in the study design; the collection, analysis or interpretation of data; the writing of the report; or in the decision to submit the manuscript for publication.
Statement of interest
None declared.
- Received January 29, 2010.
- Accepted April 21, 2010.
- ©2010 ERS