Prevalence of latent tuberculosis infection and associated risk factors among 1557 nursing students in a context of low endemicity

Introduction: The risk of tuberculosis (TBC) in nurses is related to its incidence in the general population. Nursing students involved in clinical training could be exposed to occupational risks similar to those of healthcare workers (HCWs). To better understand the epidemiology of nosocomial TBC among nurses in a context of low endemicity, we recruited a cohort of young nursing trainees at the Second University of Naples. Methods: A screening programme for LTBI in nursing students was conducted between January 2012 and December 2013, at the Second University of Naples, with clinical evaluations, tuberculin skin test (TST) and, in positive TST student, the interferon-g release assays (IGRA). Putative risk factors for LTBI were assessed by a standardized questionnaire. Results: 1577 nursing students attending the Second University of Naples have been submitted to screening programme for TBC. 1575 have performed TST as first level test and 2 Quantiferon test (QFT). 19 students were TST positive and continued the diagnostic workup practicing QFT, that was positive in 1 student. Of the 2 subjects that have practiced QFT as first level test only 1 was positive. In 2 students positive to QFT test we formulated the diagnosis of LTBI by clinical and radiographic results. Conclusion: The prevalence of LTBI among nursing students in our study resulted very low. In countries with a low incidence of TBC, the screening programs of healthcare students can be useful for the early identification and treatment of the sporadic cases of LTBI.