Rationale: In the United States, the number of annual reported cases of tuberculosis (TB) among U.S.-born persons declined by 62% from 1993 to 2004, but increased by 5% among foreign-born persons. Over half of all reported cases of TB in the United States occur among foreign-born persons, most of these due to activation of latent TB infection (LTBI). Current guidelines recommend targeting only foreign-born persons who entered the United States within the previous 5 yr for LTBI testing.
Objective: We sought to assess the epidemiologic basis for this guideline.
Methods: We calculated TB case rates among foreign-born persons, stratified by duration of United States residence and world region of origin. We determined the number of cases using 2004 U.S. TB surveillance data, and calculated case rates using population data from the 2004 American Community Survey.
Measurements and main results: In 2004, a total of 14,517 cases of TB were reported; 3,444 (24%) of these were among foreign-born persons who had entered the United States more than 5 yr previously. The rate of TB disease among foreign-born persons was 21.5/100,000, compared with 2.7/100,000 for U.S.-born persons, and varied by duration of residence and world region of origin.
Conclusions: Almost one-quarter of all TB cases in the United States occur among foreign-born persons who have resided in the United States for longer than 5 yr; case rates for such persons from selected regions of origin remain substantially elevated. To eliminate TB, we must address the burden of LTBI in this high-risk group.