Reporting Patterns and Characteristics of Tuberculosis among International Travelers, United States, June 2006 to May 2008

Abstract
Background.As part of efforts to prevent the introduction of communicable diseases into the United States, the Centers for Disease Control and Prevention (CDC) conducts surveillance for selected diseases in international travelers. One of these diseases, tuberculosis (TB), received substantial attention in May 2007 when the CDC issued travel restrictions and a federal isolation order for a person with drug-resistant TB who traveled internationally against public health recommendations. Methods.Reports of TB in international travelers in the CDC's Quarantine Activity Reporting System (QARS) from 1 June 2006 through 31 May 2007 (year 1) were compared with reports from 1 June 2007 through 31 May 2008 (year 2). These reports were classified using the CDC and American Thoracic Society guidelines and analyzed for epidemiologic characteristics and trends. Results.Among QARS reports, 4.6% were classified as active TB disease and 1.7% as no TB disease. Active TB disease reports increased from 2.5% of QARS reports in year 1 to 6.4% in year 2 (P<.001). The proportion of active TB disease reports leading to a federal travel restriction increased from 6.8% in year 1 to 15.4% in year 2 (P=.08). Conclusions.The significant increase in reports of international travelers with TB disease likely represents more attention to and a higher index of suspicion for TB. The increased use of federal travel restrictions was associated with the development of new procedures to limit travel for public health reasons. Continued efforts are needed to decrease the number of persons with TB who travel while potentially contagious.