Tuberculosis infection in children who are contacts of immigrant tuberculosis patients

The present study aimed to determine what proportion of children who are in close contact with immigrant tuberculosis (TB) patients are infected with Mycobacterium tuberculosis. For 1.5 yrs, 14 municipal health services in The Netherlands collected data from all non-Dutch TB patients and their contacts. Close contacts aged < 16 yrs received a tuberculin skin test (TST). A positive TST was defined as an induration of > or = 10 mm among nonvaccinated children, and > or = 16 mm among bacille Calmette-Guérin-vaccinated children. In total, 244 patients had 359 close contacts aged < 16 yrs. Nine out of the 359 (2.5%) had TB. A TST test was given to 298 out of the 359 (83%). Of the 115 contacts of 44 extrapulmonary TB patients, three (3%) had a positive TST. Of the 186 contacts of 58 positive pulmonary TB patients, 30 (16%) had a positive TST. Contacts of sputum smear-positive patients significantly more often had a positive TST (25%), compared with the contacts of sputum smear-negative patients (7%). Children born abroad significantly more often had a positive TST (20%) than children born in The Netherlands (5%). In conclusion, the prevalence of active tuberculosis and latent tuberculosis infection among children who are close contacts of immigrant tuberculosis patients is high and warrants an expansion of contact investigation.