Wellcome Trust, Medical Research Council, and UK National Institute for Health Research.

Latent tuberculosis infection (LTBI) screening is an important intervention for tuberculosis (TB) elimination in low-incidence countries and is, therefore, a key component of England's TB control strategy. This study describes outcomes from a LTBI screening programme in a high-incidence area to inform national LTBI screening in England and other low-incidence countries.We conducted a retrospective cohort study of LTBI screening among eligible migrants (from high-incidence countries and entered the UK within the last 5 years), who were identified at primary-care clinics in Newham, London between August 2014 and August 2015. Multivariable logistic regression was used to identify factors associated with LTBI testing uptake, interferon-γ release assay (IGRA) positivity and treatment uptake.40% of individuals offered LTBI screening received an IGRA test. The majority of individuals tested were 16–35 years old, male and born in India, Bangladesh or Pakistan. Country of birth, smoking status and co-morbidities were associated with LTBI testing uptake. IGRA positivity was 32% among those tested and was significantly associated with country of birth, age, sex and co-morbidities.This study identifies factors associated with screening uptake, IGRA positivity and treatment uptake, and improves understanding of groups that should be supported to increase acceptability of LTBI testing and treatment in the community.

Despite slightly increased cases in these areas, human infection with this cattle pathogen remains rare.

Approximately 72% of tuberculosis (TB) cases in England occur among non-UK born individuals, mostly as a result of reactivation of latent TB infection (LTBI). Programmatic LTBI screening is a key intervention of the TB strategy for England. This article reviews the results of a long-standing LTBI screening initiative in England.A retrospective cohort was created through probabilistic linkage between LTBI screening data and national TB case notifications. Screened persons were followed until they died, became a case, emigrated or until cohort-end. TB incidence rates and rate ratios (IRR) were calculated.97 out of 1820 individuals screened for LTBI were reported to have active TB. Crude incidence rates among LTBI-positive, treatment-naïve individuals were 4.1 and 2.3 per 100 person-years in the QuantiFERON and tuberculin skin test cohorts, respectively. Among the QuantiFERON cohort, Poisson regression showed that LTBI positivity (IRR 22.6, 95% CI 6.8–74.6) and no chemoprophylaxis increased the probability of becoming a TB case (IRR 0.17, 95% CI 0.05–0.6).We found high TB rates in LTBI-positive, treatment-naïve individuals and a strong association between no treatment and becoming a TB case, demonstrating feasibility and effectiveness of LTBI screening and providing important policy lessons for LTBI screening in England and beyond.