Impact of Effective Global Tuberculosis Control on Health and Economic Outcomes in the United States.

Rationale: Most U.S. residents who develop tuberculosis (TB) were born abroad, and U.S. TB incidence is increasingly driven by infection risks in other countries.Objectives: To estimate the potential impact of effective global TB control on health and economic outcomes in the United States.Methods: We estimated outcomes using linked mathematical models of TB epidemiology in the United States and migrants' birth countries. A base-case scenario extrapolated country-specific TB incidence trends. We compared this with scenarios in which countries achieve 90% TB incidence reductions between 2015 and 2035, as targeted by the World Health Organization's End TB Strategy ("effective global TB control"). We also considered pessimistic scenarios of flat TB incidence trends in individual countries.Measurements and Main Results: We estimated TB cases, deaths, and costs and the total economic burden of TB in the United States. Compared with the base-case scenario, effective global TB control would avert 40,000 (95% uncertainty interval, 29,000-55,000) TB cases in the United States in 2020-2035. TB incidence rates in 2035 would be 43% (95% uncertainty interval, 34-54%) lower than in the base-case scenario, and 49% (95% uncertainty interval, 44-55%) lower than in 2020. Summed over 2020-2035, this represents 0.8 billion dollars (95% uncertainty interval, 0.6-1.0 billion dollars) in averted healthcare costs and $2.5 billion dollars (95% uncertainty interval, 1.7-3.6 billion dollars) in productivity gains. The total U.S. economic burden of TB (including the value of averted TB deaths) would be 21% (95% uncertainty interval, 16-28%) lower (18 billion dollars [95% uncertainty level, 8-32 billion dollars]).Conclusions: In addition to producing major health benefits for high-burden countries, strengthened efforts to achieve effective global TB control could produce substantial health and economic benefits for the United States.

Overseas screening for tuberculosis in U.S.-bound immigrants and refugees.

BACKGROUND: In 2007, a total of 57.8% of the 13,293 new cases of tuberculosis in the United States were diagnosed in foreign-born persons, and the tuberculosis rate among foreign-born persons was 9.8 times as high as that among U.S.-born persons (20.6 vs. 2.1 cases per 100,000 population). Annual arrivals of approximately 400,000 immigrants and 50,000 to 70,000 refugees from overseas are likely to contribute substantially to the tuberculosis burden among foreign-born persons in the United States. METHODS: The Centers for Disease Control and Prevention (CDC) collects information on overseas screening for tuberculosis among U.S.-bound immigrants and refugees, along with follow-up evaluation after their arrival in the United States. We analyzed screening and follow-up data from the CDC to study the epidemiology of tuberculosis in these populations. RESULTS: From 1999 through 2005, a total of 26,075 smear-negative cases of tuberculosis (i.e., cases in which a chest radiograph was suggestive of active tuberculosis but sputum smears were negative for acid-fast bacilli on 3 consecutive days) and 22,716 cases of inactive tuberculosis (i.e., cases in which a chest radiograph was suggestive of tuberculosis that was no longer clinically active) were diagnosed by overseas medical screening of 2,714,223 U.S.-bound immigrants, representing prevalences of 961 cases per 100,000 persons (95% confidence interval [CI], 949 to 973) and 837 cases per 100,000 persons (95% CI, 826 to 848), respectively. Among 378,506 U.S.-bound refugees, smear-negative tuberculosis was diagnosed in 3923 and inactive tuberculosis in 10,743, representing prevalences of 1036 cases per 100,000 persons (95% CI, 1004 to 1068) and 2838 cases per 100,000 persons (95% CI, 2785 to 2891), respectively. Active pulmonary tuberculosis was diagnosed in the United States in 7.0% of immigrants and refugees with an overseas diagnosis of smear-negative tuberculosis and in 1.6% of those with an overseas diagnosis of inactive tuberculosis. CONCLUSIONS: Overseas screening for tuberculosis with follow-up evaluation after arrival in the United States is a high-yield intervention for identifying tuberculosis in U.S.-bound immigrants and refugees and could reduce the number of tuberculosis cases among foreign-born persons in the United States.

Domestic returns from investment in the control of tuberculosis in other countries.

BACKGROUND: We hypothesized that investments to improve the control of tuberculosis in selected high-incidence countries would prove to be cost saving for the United States by reducing the incidence of the disease among migrants. METHODS: Using decision analysis, we estimated tuberculosis-related morbidity, mortality, and costs among legal immigrants and refugees, undocumented migrants, and temporary visitors from Mexico after their entry into the United States. We assessed the current strategy of radiographic screening of legal immigrants plus current tuberculosis-control programs alone and with the addition of either U.S.-funded expansion of the strategy of directly observed treatment, short course (DOTS), in Mexico or tuberculin skin testing to screen legal immigrants from Mexico. We also examined tuberculosis-related outcomes among migrants from Haiti and the Dominican Republic using the same three strategies. RESULTS: As compared with the current strategy, expanding the DOTS program in Mexico at a cost to the United States of 34.9 million dollars would result in 2591 fewer cases of tuberculosis in the United States, with 349 fewer deaths from the disease and net discounted savings of 108 million dollars over a 20-year period. Adding tuberculin skin testing to radiographic screening of legal immigrants from Mexico would result in 401 fewer cases of tuberculosis in the United States but would cost an additional 329 million dollars. Expansion of the DOTS program would remain cost saving even if the initial investment were doubled, if the United States paid for all antituberculosis drugs in Mexico, or if the decline in the incidence of tuberculosis in Mexico was less than projected. A 9.4 million dollars investment to expand the DOTS program in Haiti and the Dominican Republic would result in net U.S. savings of 20 million dollars over a 20-year period. CONCLUSIONS: U.S.-funded efforts to expand the DOTS program in Mexico, Haiti, and the Dominican Republic could reduce tuberculosis-related morbidity and mortality among migrants to the United States, producing net cost savings for the United States.