Immigrants and the Spread of Tuberculosis in the United States: A Hidden Cost of Immigration

This panel-data study concerns the incidence of newly diagnosed tuberculosis (TB) in specific U.S. metropolitan areas among immigrants and, in turn, the possible transmission of the disease to the native-born population of these same metropolitan areas. The study includes 50 U.S. Metropolitan Statistical Areas as annual observations, 1993–2007. We find that a 10% increase in the number of high-incidence immigrants results in a 2.87% increase in TB among the foreign-born population, and that a 10% increase in the number of foreign-born TB cases increases the number of new TB cases among the native-born by 1.11%. The study concludes with a benefit/cost analysis of the societal cost of TB and suggests that testing all immigrants for TB would be a cost-effective method to limit the amount of TB that enters U.S. from abroad, thus limiting the transmission to both the foreign- and native-born populations.