%0 Journal Article
%T Risk of developing tuberculosis after brief exposure in Norwegian children: results of a contact investigation
%A Christina Terez Ramm
%A Eli Sagvik
%A Henrik D£¿llner
%A Ingunn Harstad
%A Jan Egil Afset
%J -
%D 2012
%R 10.1136/bmjopen-2012-001816
%X Objective Prolonged exposure to adults with pulmonary tuberculosis is a risk factor for infecting children. We have studied to what extent a brief exposure may increase the risk of being infected in children.

Design Observational study of a tuberculosis contact investigation.

Setting 7 day-care centres and 4 after-school-care centres in Norway.

Participants 606 1-year-old to 9-year-old children who were exposed briefly to a male Norwegian with smear-positive pulmonary tuberculosis.

Main outcome measures Number of children with latent and active tuberculosis detected by routine clinical examination, chest x-ray and use of a Mantoux tuberculin skin test (TST) and an interferon-¦Ã release assay (IGRA).

Results The children were exposed to a mean of 6.9£¿h (range 3¨C18£¿h). 2¨C3£¿months after the exposure, 11 children (1.8%) had a TST ¡Ý6£¿mm, 6 (1.0%) had TST 4¨C5£¿mm, and 587 (97.2%) had a negative TST result. Two children (0.3%) with negative chest x-rays who were exposed 4.75 and 12£¿h, respectively, had a positive IGRA test result, and were diagnosed with latent tuberculosis. None developed active tuberculosis.

Conclusions Children from a high-income country attending day-care and after-school-care centres had low risk of being infected after brief exposure less than 18£¿h to an adult day-care helper with smear-positive pulmonary tuberculosis
%U https://bmjopen.bmj.com/content/2/6/e001816