Inuit in the Arctic are experiencing an increase in tuberculosis cases, reaching levels as 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 M. tuberculosis infection (MTI) and the underlying annual risk of MTI. 2,231 Greenlandic school children aged 5-17 years ( approximately 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 to 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