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The online version of this article (doi:10.1186/s12889-015-2530-7) contains supplementary material, which is available to authorized users.
The authors declare that they have no competing interests.
LTW developed the decision analysis model, and participated in the drafting and revision of the manuscript. Margaret S. Coleman assisted in developing and revising the manuscript and assisted in the gathering of data. CH assisted in drafting the manuscript and assisted in gathering the data. MS helped to develop the manuscript, assisted in the preparation of supplementary tables, and contributed to the decision analysis model. WZ assisted in drafting the original manuscript and helped to devise the study. Marty S. Cetron helped to devise the study and assisted in revising the manuscript. JAP helped to devise the study, gathered data, and assisted in the development and revision of the manuscript. Marty S. Cetron and JAP contributed equally as senior authors. All authors read and approved the final manuscript.
This study explored the effect of screening and treatment of refugees for latent tuberculosis infection (LTBI) before entrance to the United States as a strategy for reducing active tuberculosis (TB). The purpose of this study was to estimate the costs and benefits of LTBI screening and treatment in United States bound refugees prior to arrival.
Costs were included for foreign and domestic LTBI screening and treatment and the domestic treatment of active TB. A decision tree with multiple Markov nodes was developed to determine the total costs and number of active TB cases that occurred in refugee populations that tested 55, 35, and 20 % tuberculin skin test positive under two models: no overseas LTBI screening and overseas LTBI screening and treatment. For this analysis, refugees that tested 55, 35, and 20 % tuberculin skin test positive were divided into high, moderate, and low LTBI prevalence categories to denote their prevalence of LTBI relative to other refugee populations.
For a hypothetical 1-year cohort of 100,000 refugees arriving in the United States from regions with high, moderate, and low LTBI prevalence, implementation of overseas screening would be expected to prevent 440, 220, and 57 active TB cases in the United States during the first 20 years after arrival. The cost savings associated with treatment of these averted cases would offset the cost of LTBI screening and treatment for refugees from countries with high (net cost-saving: $4.9 million) and moderate (net cost-saving: $1.6 million) LTBI prevalence. For low LTBI prevalence populations, LTBI screening and treatment exceed expected future TB treatment cost savings (net cost of $780,000).
Implementing LTBI screening and treatment for United States bound refugees from countries with high or moderate LTBI prevalence would potentially save millions of dollars and contribute to United States TB elimination goals. These estimates are conservative since secondary transmission from tuberculosis cases in the United States was not considered in the model.