Search

Additional file 1: Appendix 1. Search strategy.

BACKGROUND: Pillar 3 of the End TB Strategy calls for the promotion of research and innovation at the country level to facilitate improved implementation of existing and novel interventions to end tuberculosis (TB). In an era of increasing cross-border migration, there is a specific need to integrate migration-related issues into national TB research agendas. The objective of the present review is to provide a conceptual framework to guide countries in the development and operationalization of a migrant-inclusive TB research agenda. METHODS: We conducted a literature review, complemented by expert opinion and the previous articles in this State of the Art series, to identify important themes central to migration-related TB. We categorized these themes into a framework for a migration-inclusive global TB research agenda across a comprehensive spectrum of research. We developed this conceptual framework taking into account: 1) the biomedical, social and structural determinants of TB; 2) the epidemiologic impact of the migration pathway; and 3) the feasibility of various types of research based on a country's capacity. DISCUSSION: The conceptual framework presented here is based on the key principle that migrants are not inherently different from other populations in terms of susceptibility to known TB determinants, but that they often have exacerbated or additional risks related to their country of origin and the migration process, which must be accounted for in developing comprehensive TB prevention and care strategies. A migrant-inclusive research agenda should systematically consider this wider context to have the highest impact.

Introduction\ud \ud Despite the close link between tuberculosis (TB) and poverty, most mathematical models of TB have not addressed underlying social and structural determinants (SD). In this paper, we review studies employing mathematical modelling to evaluate the epidemiological impact of SD of TB. \ud \ud Methods\ud \ud We systematically searched PubMed and personal libraries to identify eligible papers. We extracted data on modelling techniques employed, research question, type of SDs modelled, and setting. \ud \ud Results \ud \ud From 232 records identified, we included eight papers published between 2008 and 2015; six employed population-based dynamic TB transmission models and two non-dynamic analytic models. Seven studies focused on proximal TB determinants (four on nutritional status, one on wealth, one on indoor air pollution, and one examined overcrowding, socioeconomic and nutritional status), and one focused on macroeconomic influences. \ud \ud Conclusions\ud \ud Few modelling studies have attempted to evaluate SD of TB, resulting in key knowledge gaps. Despite challenges of modelling such a complex system, models must broaden their scope to remain useful for policy making. Given the inter-sectoral nature of the interrelations between SD and TB outcomes, this work will require multi-disciplinary collaborations. A useful starting point would be to focus on developing relatively simple models that can strengthen our knowledge regarding the potential effect of SD on TB outcomes. \ud

BACKGROUND: Screening for tuberculosis (TB) disease aims to improve early TB case detection. The ultimate goal is to improve outcomes for people with TB and to reduce Mycobacterium tuberculosis transmission in the community through improved case detection, reduction in diagnostic delays and early treatment. Before screening programmes are recommended, evidence is needed of individual and/or community-level benefits. METHODS: We conducted a systematic review of the literature to assess the evidence that screening for TB disease 1) initially increases the number of TB cases initiated on anti-tuberculosis treatment, 2) identifies cases earlier in the course of disease, 3) reduces mortality and morbidity, and 4) impacts on TB epidemiology. RESULTS: A total of 28 798 publications were identified by the search strategy: 27 087 were excluded on initial screening and 1749 on full text review, leaving 62 publications that addressed at least one of the study questions. Screening increases the number of cases found in the short term. In many settings, more than half of the prevalent TB cases in the community remain undiagnosed. Screening tends to find cases earlier and with less severe disease, but this may be attributed to case-finding studies using more sensitive diagnostic methods than routine programmes. Treatment outcomes among people identified through screening are similar to outcomes among those identified through passive case finding. Current studies provide insufficient evidence to show that active screening for TB disease impacts on TB epidemiology. CONCLUSION: Individual and community-level benefits from active screening for TB disease remain uncertain. So far, the benefits of earlier diagnosis on patient outcomes and transmission have not been established.

The impact of current interventions to improve early detection of tuberculosis (TB) seems to have been saturated. Case detection trends have stagnated. TB incidence is falling in most settings worldwide, but the rate of decline is far lower than expected. There is growing evidence from national TB prevalence surveys and other research of a large pool of undetected TB in the community. Intensified efforts to further break down access barriers and scale up new and rapid diagnostic tools are likely to improve the situation. However, will these be enough? Or do we also need to reach out more towards people who do not actively seek care with well-recognisable TB symptoms? There have recently been calls to revisit TB screening, particularly in high-risk groups. The World Health Organization (WHO) recommends screening for TB in people with human immunodeficiency virus infection and in close TB contacts. Should other risk groups also be screened systematically? Could mass, community-wide screening, which the WHO has discouraged over the past four decades, be of benefit in some situations? If so, what screening tools and approaches should be used? The WHO is in the process of seeking answers to these questions and developing guidelines on systematic screening for active TB. In this article, we present the rationale, definitions and key considerations underpinning this process.

Objective: To quantify the impact of cash transfer and microfinance interventions on a selected list of tuberculosis (TB) risk factors and assess their potential role in supporting TB control. DATA SOURCE: Published and unpublished references identified from clinical and social electronic databases, grey literature and web sites. METHODS: Eligible interventions had to be conducted in middle- or low-income countries and document an impact evaluation on any of the following outcomes: 1) TB or other respiratory infections; 2) household socioeconomic position; and 3) factors mediating the association between low household socio-economic position and TB, including inadequate health-seeking behaviours, food insecurity and biological TB risk factors such as human immunodeficiency virus (HIV) and adult malnutrition. Interventions targeting special populations were excluded. RESULTS: Fifteen cash transfer schemes (four unconditional and 11 conditional) and seven microfinance programmes met the eligibility criteria. No intervention addressed TB or any other respiratory infection. Of 11 cash transfer and four microfinance interventions, respectively seven and four reported a positive impact on indicators of economic well-being. A positive impact on household food security was documented in respectively eight of nine and three of five cash transfer and microfi nance interventions. Improved health care access was documented respectively in 10 of 12 cash transfer and four of five microfinance interventions. The only intervention evaluating impact on HIV incidence was a microfi nance project that found no effect. No cash transfer or microfinance interventions had an impact on adult malnutrition. CONCLUSIONS: Cash transfer and microfinance interventions can positively impact TB risk factors. Evaluation studies are urgently needed to assess the impact of these social protection interventions on actual TB indicators.