Reducing the burden of TB among migrants to low TB incidence countries.

BACKGROUND: International migrants to low TB incidence countries are disproportionately affected by TB compared to the native population: migrants are at increased risk for TB transmission and TB disease due to a variety of personal, environmental and socio-economic determinants experienced during the four phases of migration (pre-departure, transit, arrival and early settlement, return travel).OBJECTIVE: To provide an up-to-date overview of the determinants that drive the TB burden among migrants, as well as effective and feasible interventions to address this for each migration phase.METHODS: We conducted a literature review by searching PubMed and the grey literature for articles and reports on determinants and interventions addressing migrant health and TB.RESULTS: Lowering the risk of TB transmission and TB disease among migrants would be most effective by improving the socio-economic position of migrants pre-, during and after migration, ensuring universal health coverage, and providing tailored and migrant-sensitive care and prevention activities.CONCLUSION: In addition to migrant-sensitive health services and cross-border collaboration between low TB incidence countries, there is a need for international financial and technical support for endemic countries.

The household economic burden of drug-susceptible TB diagnosis and treatment in The Gambia.

OBJECTIVE: To determine the costs and catastrophic costs incurred by drug-susceptible (DS) pulmonary TB patients in The Gambia.METHODS: This observational study collected cost and socio-economic data using a micro-costing approach from the household perspective from 244 adult DS-TB patients with pulmonary TB receiving treatment through the national treatment programme in The Gambia. We used data collected between 2017 and 2020 using an adapted version of the WHO generic patient cost survey instrument to estimate costs and the proportion of patients experiencing catastrophic costs (≥20% of household income).RESULTS: The mean total cost of the TB episode was $104.11 (2018 USD). Direct costs were highest before treatment ($22.93). Indirect costs accounted for over 50% of the entire episode costs. Using different income estimation approaches and catastrophic cost thresholds, 0.4-75% of participants encountered catastrophic costs, showing the variability of results given the different assumptions we utilised.CONCLUSIONS: We show that despite the benefits of free TB care and treatment, DS-TB patients still incur substantial direct and indirect costs, and cases of impoverishing expenditure varied vastly depending on the income estimation approaches used.

The socioeconomic impact of tuberculosis on children and adolescents: a scoping review and conceptual framework.

BACKGROUND: Tuberculosis (TB) has been repeatedly shown to have socioeconomic impacts in both individual-level and ecological studies; however, much less is known about this effect among children and adolescents and the extent to which being affected by TB during childhood and adolescence can have life-course implications. This paper describes the results of the development of a conceptual framework and scoping review to review the evidence on the short- and long-term socioeconomic impact of tuberculosis on children and adolescents. OBJECTIVES: To increase knowledge of the socioeconomic impact of TB on children and adolescents. METHODS: We developed a conceptual framework of the socioeconomic impact of TB on children and adolescents, and used scoping review methods to search for evidence supporting or disproving it. We searched four academic databases from 1 January 1990 to 6 April 2021 and conducted targeted searches of grey literature. We extracted data using a standard form and analysed data thematically. RESULTS: Thirty-six studies (29 qualitative, five quantitative and two mixed methods studies) were included in the review. Overall, the evidence supported the conceptual framework, suggesting a severe socioeconomic impact of TB on children and adolescents through all the postulated pathways. Effects ranged from impoverishment, stigma, and family separation, to effects on nutrition and missed education opportunities. TB did not seem to exert a different socioeconomic impact when directly or indirectly affecting children/adolescents, suggesting that TB can affect this group even when they are not affected by the disease. No study provided sufficient follow-up to observe the long-term socioeconomic effect of TB in this age group. CONCLUSION: The evidence gathered in this review reinforces our understanding of the impact of TB on children and adolescents and highlights the importance of considering effects during the entire life course. Both ad-hoc and sustainable social protection measures and strategies are essential to mitigate the socioeconomic consequences of TB among children and adolescents.

Country differences and determinants of yield in programmatic migrant TB screening in four European countries.

INTRODUCTION The WHO End TB Strategy emphasises early diagnosis and screening of TB in high-risk groups, including migrants. We analysed TB yield data from four large migrant TB screening programmes to inform TB policy.METHODS We pooled routinely collected individual TB screening episode data from Italy, the Netherlands, Sweden and the United Kingdom under the European Union Commission E-DETECT.TB grant, described characteristics of the screened population, and analysed TB case yield.RESULTS We collected data on 2,302,260 screening episodes among 2,107,016 migrants, mostly young adults aged 18-44 years (77.8%) from Asia (78%) and Africa (18%). There were 1,658 TB cases detected through screening, with substantial yield variation (per 100,000): 201.1 for Sweden (95% confidence intervals CI 111.4-362.7), 68.9 (95% CI 65.4-72.7) for the United Kingdom, 83.2 (95% CI 73.3-94.4) for the Netherlands and 653.6 (95% CI 445.4-958.2) in Italy. Most TB cases were notified among migrants from Asia (n = 1,206, 75/100,000) or Africa (n = 370, 76.4/100,000), and among asylum seekers (n = 174, 131.5/100,000), migrants to the Netherlands (n = 101, 61.9/100,000) and settlement visa migrants to the United Kingdom (n = 590, 120.3/100,000).CONCLUSIONS We found considerable variations in yield across programmes, types of migrants and country of origin. These variations may be partly explained by differences in migration patterns and programmatic characteristics.

Different disease, same challenges: Social determinants of tuberculosis and COVID-19.

Infectious diseases, such as tuberculosis (TB) and the novel coronavirus (COVID-19) relate to environmental factors, understanding of which is essential to inform policy and practice and tackle them effectively. The review follows the conceptual framework offered by the World Health Organization Commission on Social Determinants of Health (defined as "all those material, psychological and behavioural circumstances linked to health and generically indicated as risk factors' in the conventional epidemiological language"). It describes the social factors behind TB and COVID-19, the commonalities between the two diseases, and what can be learned so far from the published best practices. The social determinants sustaining TB and COVID-19 underline the importance of prioritising health and allocating adequate financial and human resources to achieve universal health coverage and health-related social protection while addressing the needs of vulnerable populations. Rapid and effective measures against poverty and other major social determinants and sources of inequality are urgently needed to develop better health in the post-COVID-19 world.

ScreenTB: a tool for prioritising risk groups and selecting algorithms for screening for active tuberculosis.

SETTING AND OBJECTIVES: There is an urgent need to improve tuberculosis (TB) case detection globally. This would require greater focus on the implementation of TB screening programs. However, to be productive, cost-effective, and ethical, TB screening efforts should be tailored to their local context, targeted to the populations most likely to benefit and utilizing diagnostic tools with sufficient accuracy.DESIGN AND RESULTS: We have developed an online tool, ScreenTB to help National TB Programmes (NTPs) and their partners plan TB screening activities by modeling the potential outcomes of screening programs, including yield of TB cases diagnosed (true- and false-positives), costs, and cost-effectiveness, specific to the populations screened and the diagnostic algorithms used. In Myanmar, ScreenTB was used to assist the NTP in prioritizing risk groups for screening efforts and selecting appropriate screening algorithms to maximize case detection and minimize false-positive diagnoses.CONCLUSION: The ScreenTB tool can help facilitate the prioritization of risk groups for screening and the selection of appropriate screening algorithms. This is useful when used as part of a larger planning process that considers feasibility of screening, vulnerability of risk groups, potential impact of screening on TB transmission, human rights implications of screening and equity in health care access.

Measuring the economic burden for TB patients in the End TB Strategy and Universal Health Coverage frameworks.

Tuberculosis (TB) is a disease of poverty. Ensuring access to health care without the risk of financial hardship due to out-of-pocket health care expenditures (Universal Health Coverage [UHC]) is essential for providing accessible care to underprivileged populations, but this is not enough. The End TB Strategy promotes both patient-centred TB services and social protection measures, which aim to mitigate the economic hardship faced by TB patients and their households due to direct medical and non-medical expenditures, as well as to lost income. The strategy includes a target that no families should face catastrophic total costs due to TB. The indicator linked to this target aims to capture the total economic burden linked to TB care, and thus differs from the 'catastrophic expenditure on health' indicator, a key component of the UHC monitoring framework aligned with the Sustainable Development Goals. Countries, and particularly high TB burden countries, are expected to conduct nationally representative TB patient cost surveys to establish baseline measurements for the catastrophic costs indicator. Findings from these surveys should also help identify entry points for developing policies to ensure better financial and social protection for TB patients. In this paper, we define the key measurable concepts for TB patient cost surveys, notably the types of costs that are captured, and related affordability measures. We discuss methods for measuring these notions in the UHC framework and contrast them with how they are measured in TB patient cost surveys.

Measuring catastrophic costs due to tuberculosis in Viet Nam.

INTRODUCTION: Progress towards ending tuberculosis (TB) in Viet Nam includes monitoring the costs borne by patients through periodic facility-based surveys. OBJECTIVE: To document the magnitude of costs incurred by TB-affected households and establish a baseline for the top End TB indicator in Viet Nam. METHODS: A national survey with retrospective data collection and projection among 735 participants in 20 stratified clusters was conducted in 2016. Each patient was interviewed on costs, time loss, coping measures and asset ownership. Total costs were expressed as a proportion of annual household income. RESULTS: In Viet Nam, 63% of households affected by TB or multidrug-resistant TB (MDR-TB) experienced costs that were >20% of their annual household income. The mean patient costs were respectively US$1054 and US$4302 per episode of TB and MDR-TB. The most significant drivers of mean costs were income loss reported and purchase of special foods, nutritional supplements, travel and accommodation. CONCLUSION: The proportion of households experiencing catastrophic total costs due to TB in Viet Nam is high, which poses a barrier to TB diagnosis and treatment. Based on study results, programme and partners need to identify key areas for policy action and work towards a national policy guide on intervention to reduce TB patient costs.

Defining a migrant-inclusive tuberculosis research agenda to end TB.

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.

Modelling the impact of social protection on tuberculosis: the S-PROTECT project.

BACKGROUND: Tackling the social determinants of Tuberculosis (TB) through social protection is a key element of the post-2015 End TB Strategy. However, evidence informing policies are still scarce. Mathematical modelling has the potential to contribute to fill this knowledge gap, but existing models are inadequate. The S-PROTECT consortium aimed to develop an innovative mathematical modelling approach to better understand the role of social protection to improve TB care, prevention and control. METHODS: S-PROTECT used a three-steps approach: 1) the development of a conceptual framework; 2) the extraction from this framework of three high-priority mechanistic pathways amenable for modelling; 3) the development of a revised version of a standard TB transmission model able to capture the structure of these pathways. As a test case we used the Bolsa Familia Programme (BFP), the Brazilian conditional cash transfer scheme. RESULTS: Assessing one of these pathways, we estimated that BFP can reduce TB prevalence by 4% by improving households income and thus their nutritional status. When looking at the direct impact via malnutrition (not income mediated) the impact was 33%. This variation was due to limited data availability, uncertainties on data transformation and the pathway approach taken. These results are preliminary and only aim to serve as illustrative example of the methodological challenges encountered in this first modelling attempt, nonetheless they suggest the potential added value of integrating TB standard of care with social protection strategies. CONCLUSIONS: Results are to be confirmed with further analysis. However, by developing a generalizable modelling framework, S-PROTECT proved that the modelling of social protection is complex, but doable and allowed to draw the research road map for the future in this field.

Tuberculosis, social determinants and co-morbidities (including HIV).

The risk of exposure, progression to active tuberculosis (TB) and then to cure is a process affected by several risk factors. Along with well known risk factors such as human immunodeficiency virus (HIV), use of immunosuppressive drugs and being of young age, emerging risk factors such socio-economic and behavioral aspects play a significant role in increasing the susceptibility to infection, and unsuccessful treatment outcomes. This paper summarizes the effects of these socio-economic determinants and co-morbidities (including HIV) on TB infection and disease.

Modelling the social and structural determinants of tuberculosis: opportunities and challenges.

INTRODUCTION: Despite the close link between tuberculosis (TB) and poverty, most mathematical models of TB have not addressed underlying social and structural determinants. OBJECTIVE: To review studies employing mathematical modelling to evaluate the epidemiological impact of the structural determinants of TB. METHODS: We systematically searched PubMed and personal libraries to identify eligible articles. We extracted data on the modelling techniques employed, research question, types of structural determinants modelled and setting. RESULTS: From 232 records identified, we included eight articles 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, socio-economic and nutritional status), and one focused on macro-economic influences. CONCLUSIONS: Few modelling studies have attempted to evaluate structural determinants of TB, resulting in key knowledge gaps. Despite the challenges of modelling such a complex system, models must broaden their scope to remain useful for policy making. Given the intersectoral nature of the interrelations between structural determinants and TB outcomes, this work will require multidisciplinary collaborations. A useful starting point would be to focus on developing relatively simple models that can strengthen our knowledge regarding the potential effect of the structural determinants on TB outcomes.

Methodological considerations for economic modelling of latent tuberculous infection screening in migrants.

Tuberculosis (TB) in migrants from endemic to low-incidence countries results mainly from the reactivation of latent tuberculous infection (LTBI). LTBI screening policies for migrants vary greatly between countries, and the evidence on the cost-effectiveness of the different approaches is weak and heterogeneous. The aim of this review was to assess the methodology used in published economic evaluations of LTBI screening among migrants to identify critical methodological options that must be considered when using modelling to determine value for money from different economic perspectives. Three electronic databases were searched and 10 articles were included. There was considerable variation across this small number of studies with regard to economic perspective, main outcomes, modelling technique, screening options and target populations considered, as well as in parameterisation of the epidemiological situation, test accuracy, efficacy, safety and programme performance. Only one study adopted a societal perspective; others adopted a health care or wider government perspective. Parameters representing the cascade of screening and treating LTBI varied widely, with some studies using highly aspirational scenarios. This review emphasises the need for a more harmonised approach for economic analysis, and better transparency in how policy options and economic perspectives influence methodological choices. Variability is justifiable for some parameters. However, sufficient data are available to standardise others. A societal perspective is ideal, but can be challenging due to limited data. Assumptions about programme performance should be based on empirical data or at least realistic assumptions. Results should be interpreted within specific contexts and policy options, with cautious generalisations.

Tuberculosis in migrants in low-incidence countries: epidemiology and intervention entry points.

As tuberculosis (TB) rates continue to decline in native populations in most low TB incidence countries, the proportion of TB patients born outside their country of residence ('foreign-born') increases. Some low-incidence countries have experienced a substantial increase in TB rates related to recent increases in the number of asylum seekers and other migrants from TB-endemic countries. However, average TB rates among the foreign-born in low-incidence countries declined moderately in 2009-2015. TB in foreign-born individuals is commonly the result of reactivation of latent infection with Mycobacterium tuberculosis acquired outside the host country. Transmission is generally low in low-incidence countries, and transmission from migrants to the native population is often modest. Variations in levels and trends in TB notifications among the foreign-born are likely explained by differences and fluctuations in the number and profile of migrants, as well as by variations in TB control, health and social policies in the host countries. To optimise TB care and prevention in migrants from endemic to low-incidence countries, we propose a framework for identifying possible TB care and prevention interventions before, during and after migration. Universal access to high-quality care along the entire migration pathway is critical. Screening for active TB and latent tuberculous infection should be tailored to the TB epidemiology, adapted to the needs of specific migrant groups and linked to treatment. Ultimately, the long-term TB elimination goal can be reached only if global health and socio-economic inequalities are dramatically reduced. Low-incidence countries, most of which are among the wealthiest nations, need to contribute through international assistance.

Multidrug-resistant tuberculosis and migration to Europe.

Multidrug-resistant tuberculosis (MDR-TB) in low-incidence countries in Europe is more prevalent among migrants than the native population. The impact of the recent increase in migration to EU and EEA countries with a low incidence of TB (<20 cases per 100 000) on MDR-TB epidemiology is unclear. This narrative review synthesizes evidence on MDR-TB and migration identified through an expert panel and database search. A significant proportion of MDR-TB cases in migrants result from reactivation of latent infection. Refugees and asylum seekers may have a heightened risk of MDR-TB infection and worse outcomes. Although concerns have been raised around 'health tourists' migrating for MDR-TB treatment, numbers are probably small and data are lacking. Migrants experience significant barriers to testing and treatment for MDR-TB, exacerbated by increasingly restrictive health systems. Screening for latent MDR-TB is highly problematic because current tests cannot distinguish drug-resistant latent infection, and evidence-based guidance for treatment of latent infection in contacts of MDR patients is lacking. Although there is evidence that transmission of TB from migrants to the general population is low-it predominantly occurs within migrant communities-there is a human rights obligation to improve the diagnosis, treatment and prevention of MDR-TB in migrants. Further research is needed into MDR-TB and migration, the impact of screening on detection or prevention, and the potential consequences of failing to treat and prevent MDR-TB among migrants in Europe. An evidence-base is urgently needed to inform guidelines for effective approaches for MDR-TB management in migrant populations in Europe.

Diabetes mellitus and tuberculosis: programmatic management issues.

In August 2011, the World Health Organization and the International Union Against Tuberculosis and Lung Disease launched the Collaborative Framework for Care and Control of Tuberculosis (TB) and diabetes mellitus (DM) to guide policy makers and implementers in combatting the epidemics of both diseases. Progress has been made, and includes identifying how best to undertake bidirectional screening for both diseases, how to provide optimal treatment and care for patients with dual disease and the most suitable framework for monitoring and evaluation. Key programmatic challenges include the following: whether screening should be directed at all patients or targeted at those with high-risk characteristics; the most suitable technologies for diagnosing TB and diabetes in routine settings; the best time to screen TB patients for DM; how to provide an integrated, coordinated approach to case management; and finally, how to persuade non-communicable disease programmes to adopt a cohort analysis approach, preferably using electronic medical records, for monitoring and evaluation. The link between DM and TB and the implementation of the collaborative framework for care and control have the potential to stimulate and strengthen the scale-up of non-communicable disease care and prevention programmes, which may help in reducing not only the global burden of DM but also the global burden of TB.