Effectiveness and cost-effectiveness of screening migrants for active tuberculosis and latent tuberculous infection.

With the advent of the World Health Organization End TB strategy, there has been renewed interest in screening for active tuberculosis (TB), and particularly latent tuberculous infection (LTBI). In low-incidence countries, a high proportion of TB cases are notified among migrants, which often occurs due to LTBI reactivation. We aimed to review the effectiveness and cost-effectiveness of screening migrants for active TB LTBI to inform and support the TB elimination strategy in low-incidence countries. We carried out a narrative review of English language articles published between 1 January 2000 and 31 June 2016 using the PubMed database. All studies that described the effectiveness or cost-effectiveness of active TB or LTBI screening among migrants were included. We identified 55 studies, and included 40 for the effectiveness of screening, 11 for cost-effectiveness and 4 that reported both. Screening for active TB can be effective and cost-effective depending on the setting, target group and screening approach. Pre-entry screening programmes have some impact on the epidemiology of the receiving countries. The effectiveness and cost-effectiveness of LTBI screening as predicted in mathematical models is also highly setting-specific, with best potential results achieved if screening is restricted to high-risk groups and/or to migrants from high-burden countries.