Treatment of latent tuberculosis infection in contacts of new tuberculosis cases in the United States.

BACKGROUND

Few data are available describing treatment completion rates among recently infected contacts of tuberculosis (TB) cases, a group at high risk for development of active TB.

METHODS

Health department records were reviewed for all contacts of 360 culture-positive pulmonary TB cases reported from five health departments in the United States in 1996.

RESULTS

Of 2,267 contacts who completed screening, 630 (28%) had newly documented positive skin tests (121 with skin test conversion). Treatment of latent TB infection was documented to have been recommended for 447 (71%). Among these, treatment was documented to be initiated for 398 (89%). Of these, 203 (51%) were documented to have completed a 6-month course of treatment, and 78 (20%) received directly observed treatment. Treatment was recommended more often for contacts < 15 years of age, skin test converters, close contacts, and contacts of smear-positive cases. Treatment completion rates were higher for skin test converters.

CONCLUSIONS

In this study, fewer than one third of all persons with newly documented positive skin tests detected during contact investigations were proven to have completed treatment. Achieving high rates of completion of therapy for latent TB infection in recently infected contacts of active cases of pulmonary TB is essential to maximize public health prevention efforts aimed at eliminating TB.