Latent Tuberculosis Infection in a Cohort of Refugee Patients Resettling in New England

Abstract

Background. The majority of active tuberculosis (TB) in the United States is reactivation of untreated latent TB infection. Most of these cases are diagnosed in foreign-born persons. Refugees represent a population of foreign-born persons with several potential risk factors for TB exposure. Thus, identification and treatment of latent TB in refugee patients are public health priorities. The purpose of this study was to evaluate the epidemiology of latent TB infection in a cohort of refugee patients. Methods. We conducted a retrospective cohort study of adult refugees (age > 18 years) who resettled in New Haven County, an urban area of Connecticut between June 2013 - December 2015. Patients were evaluated in a centralized refugee clinic for medical screening within two months of arrival to the United States. Refugees were screened for latent TB infection with either tuberculin skin testing or interferon- gamma release assay. Those testing positive were referred for treatment within the same health system. For all patients screened during the study period, we collected demographic and clinical data. We assessed the proportion of patients with latent TB infection and stratified results by gender, country of origin, and method of screening. Results. In total, 408 adult refugees were resettled in New Haven county from June 2013 to December 2015. Of these, 402 (98.5%) were screened for latent TB infection. 25.2% of these patients screened positive for latent TB. Patients with latent TB originated primarily from Sub-Saharan Africa, the Middle East, and East Africa. Similar proportions of latent TB infection was observed among males and female patients. All patients with latent TB infection were referred for treatment, but several did not complete therapy. Demographic and clinical characteristics of those not completing treatment are described in this study. Conclusion. A large proportion of adult refugees resettling in the USA have latent TB infection, a substantial fraction of whom do not complete therapy. These findings have public health implications for a growing refugee and asylum-seeking population worldwide.