Racial disparities in primary and reactivation tuberculosis in a rural community in the southeastern United States

SETTING: A rural section of a county in central Florida. BACKGROUND: Racial disparities in tuberculosis disease (TB) are substantial in the United States. OBJECTIVE: To determine if TB was attributable to primary infection, reactivation or both. DESIGN: A population-based survey of latent tuberculosis infection (LTBI), a case-control analysis of TB, and a cluster analysis of TB isolates were performed between 1997 and 2001. RESULTS: Of 447 survey participants, 135 (30%) had LTBI. Black race was strongly associated with LTBI among US-born (OR 2.6, 95%CI 1.3-5.5) and foreign-born subjects (OR 4.3, 95%CI 2.2-8.4). Risk factors for TB included human immunodeficiency virus (HIV; OR 27.4, 95%CI 10.1-74.1), drug use (OR 4.6, 95%CI 1.7-12.4) and Black race (OR 3.4, 95%CI 1.2-9.6). The population risk of TB attributable to Black race was 64%, while that attributable to HIV was 46%. Cluster analysis showed 67% of TB cases were clustered, but Blacks were not at a significantly increased risk of having a clustered isolate (OR 2.1, 95%CI 0.12-36.0). CONCLUSION: Both reactivation TB and recent TB transmission were increased among Blacks in this community. Therefore, LTBI screening and intensive contact tracing, both followed by LTBI treatment, will be needed to reduce TB in Blacks.