Tuberculosis infection and disease in the 2015 cohort of unaccompanied minors seeking asylum in Northern Stockholm, Sweden

Background: Minors with a stated age <18 years unaccompanied by a responsible adult form an increasing part of refugees to Europe. They are older than other asylum-seeking children and many come from countries with a high tuberculosis (TB) incidence. During the 2015 refugee crisis, 35,369 of 162,877 refugees (22%) seeking asylum in Sweden were unaccompanied minors, which gave us the opportunity to study their burden of TB infection and disease. Methods: Of the unaccompanied minors seeking asylum in Sweden during 2015, 2936 (8.3%) were allocated to northern Stockholm. Of these, 2422 were from countries with an incidence of TB exceeding 100/10(5), and were screened for TB infection with a Mantoux tuberculin skin test or a QuantiFERON-TB Gold (R). Those from countries with a lower TB incidence were screened only if they had other risk factors for TB exposure. Results: Of those screened, 349 had a positive test and were referred to the northern paediatric TB clinic at Astrid Lindgren Children's Hospital. Of these, 16 had TB disease and 278 latent tuberculosis infection (LTBI), while we considered 53 uninfected. In addition, eight sought medical attention with symptomatic TB outside the screening system. Cohort rates were 6.8% of LTBI and 0.5% of TB in minors from Afghanistan and 26-32% of LTBI and 3.4-3.5% of TB among those from Eritrea, Ethiopia or Somalia. Conclusion: We conclude that TB infection and disease is common among asylum-seeking unaccompanied minors, especially among those from the Horn of Africa.