Reversing the tide of the UK tuberculosis epidemic.

In the UK, tuberculosis is an urgent public health problem, particularly for immigrants and other socially deprived and vulnerable groups. London has the highest rate of tuberculosis of any western European capital. Although recently improved National Health Service tuberculosis services aimed at early diagnosis and initiatives to prevent transmission in hard-to-reach groups are in place, these measures are unlikely to reverse the tide. Present trends of tuberculosis in the UK suggest that, within the next 2 years, the UK will have more new tuberculosis cases than the whole of the USA (fi gure). Eff ective strategies to tackle tuberculosis in the UK will need to be tailored to its epidemiology. Some London boroughs have rates higher than parts of sub-Saharan Africa. Proactive programmes for screening, prevention, and treatment, targeting defi ned high-risk pop ulations (eg, Find and Treat), need to be strengthened. For tuber culosis cases diagnosed in immigrants, although only a small number occur within the fi rst year of entry, nearly half are diagnosed within 5 years of arrival, which suggests that latent tuberculosis infection (LTBI) often occurs overseas. By contrast with the New York epidemic in the early 1990s, in which transmission events determined the increase in tuberculosis rates, in the UK the role of reactivation of remotely acquired LTBI is supported by molecular epidemiological studies. Robust evidence suggests that LTBI screening and treatment can prevent tuberculosis, is cost eff ective, and is feasible to implement in primary care. For example, a previous analysis showed that targeted screening for LTBI is cost eff ective for immigrants from areas with a tuberculosis incidence of more than 150 cases per 100 000 population, costing £20 818 (US$32 532) per case prevented. More recent data suggest that treatment can be shortened and the pill burden reduced, potentially improving adherence. The acceptability of screening in the community also seems to be high. In Europe, renewed interest has led to new initiatives for a programmatic approach to latent tuberculosis. In the UK, screening for latent tuberculosis has been recommended by the UK National Institute for Health and Care Excellence since 2006, but implementation has been variable. This variation results from the fact that implementation is the responsibility of local health commissioners, and is therefore subject to local resourcing priorities with no coherent national approach to identify tuberculosis control as a priority. A national approach for tuberculosis is being developed, and aims to achieve a year-on-year reduction of new cases. In London, a target of 50% incidence reduction within the next 5 years has been set. To achieve these targets, screening initiatives for latent tuberculosis need to be better coordinated and targeted. To promote such coordination and to form a consensus, stakeholders at a recent national workshop held in London agreed to develop a coherent screening strategy for LTBI for presentation to the national screening committee. On the basis of the present proposal for a national programme, workshop participants considered screening eligibility criteria, ways to identify individuals for screening, acceptability issues, screening and treatment pathways, and the evaluation of LTBI screening. Several challenges were identifi ed and solutions proposed, including strategies to promote screening uptake, and to manage potential hepatic toxicity by carefully selecting outpatients with pre-existing liver disease. A programme to screen for active tuberculosis before arrival to the UK is already in place, but does not detect LTBI in immigrants living in the UK, disadvantaged and vulnerable communities, or people at risk as a result of immunosuppressive therapy. A quality-assured,