Latent tuberculous screening of recent migrants attending language classes: a cohort study and cost analysis.

Abstract

SETTING: England's national tuberculosis (TB) strategy recommends testing for and treatment of latent tuberculous infection (LTBI) among new migrants. Programmatic testing occurs in primary care, which may be inaccessible for some individuals. Current strategies could therefore be complemented by screening in other settings. OBJECTIVE: To investigate the feasibility and effectiveness of LTBI screening in a community college. DESIGN: A cohort study using observational data collected during the pilot study. Eligible students from high-incidence countries provided consent and were tested with a single-step interferon-gamma release assay (IGRA) and enrolled. We used single and multivariable analyses to estimate screening effectiveness and to explore different subgroups. We included costs from a UK National Health Service perspective. RESULTS: Screening uptake was 75% and treatment completion was 85%. Of 440 students, 71 (16%) were LTBI-positive; two had active TB. There was an association of positivity with age and incidence in the country of origin. Three incidence thresholds met our criteria for screening: countries with >40, >100 and >200 cases per 100 000 population, plus students from sub-Saharan Africa. CONCLUSION: We found that LTBI screening can be offered effectively in a community college, and could be a complement to primary care-based programmes in low-incidence countries.