Tuberculosis screening for prospective migrants to high-income countries: systematic review of policies

Impact of a TB Team on TB Outcomes: A 2016-2024 Pre-Post Study From a Referral Center in Southern Italy

Background

Tuberculosis (TB) remains a major global public health challenge, requiring innovative management strategies to improve patient outcomes and reduce disease burden. Despite advancements in diagnostics and treatment, TB continues to cause significant morbidity and mortality worldwide, particularly among vulnerable populations such as migrants and individuals with limited healthcare access. The World Health Organization has emphasized the need for patient-centered approaches, including the establishment of TB-dedicated teams, to enhance care coordination and improve outcomes. However, real-world evidence on their effectiveness remains limited.

Methods

We conducted a retrospective before-after study to evaluate the impact of a structured TB-dedicated team implemented at a referral hospital in Southern Italy between 2016 and 2024. Prior to 2020, TB care was unstructured, with patients being followed by different physicians without a standardized system. Between 2021 and 2024, a dedicated TB team was established, comprising 2 infectious disease specialists, infectious disease residents, and a senior professor overseeing scientific activities. This new model introduced key interventions, including a dedicated outpatient reservation system, directly observed therapy, structured follow-up, specialist networking, systematic data collection, and targeted counseling on risk behaviors and comorbidities. Primary outcomes included treatment success rates, hospital length of stay, incidence of adverse events, and patient retention in follow-up programs. All tests were 2-sided and a P-value <.05 was considered statistically significant. Statistical analysis was carried out using R 4.4.

Results

A total of 269 TB patients were analyzed (117 pre- and 152 postimplementation). The introduction of the TB team was associated with a significant reduction in loss to follow-up (41.9% to 3.7%; P < .0001; odds ratio, 0.04; 95% confidence interval, .01-.12) and incomplete treatments (41.9% to 12.0; P < .0001; odds ratio, 0.13; 95% confidence interval, .06-.29). Median hospital stay decreased from 28 to 14 days (P < .0001), whereas adverse events remained comparable (32.5% vs 29.6%, P = .71).

Conclusions

The implementation of a TB-dedicated team significantly improved TB management by enhancing treatment adherence, reducing hospitalization, and preventing loss to follow-up. Given the public health impact of TB, structured care models should be prioritized to optimize patient outcomes and strengthen health system efficiency.

Exposure Time to a Tuberculosis Index Case as a Marker of Infection in Immigrant Populations

Background: Exposure time to a tuberculosis (TB) index case may be a marker of a recent latent tuberculosis infection (LTBI) risk. The aim of this study was to determine the LTBI risk involved in immigrant contact based on exposure time to pulmonary TB index cases. Methods: We conducted a 30-month LTBI prevalence study of pulmonary TB immigrant contacts in Catalonia (1 January 2019-30 June 2021). Contacts with LTBI were identified by means of the tuberculin skin test and/or interferon gamma release assay. Variables associated with LTBI in contacts were analysed using adjusted OR (aOR) and 95% confidence interval (CI) values. Results: LTBI prevalence was 37.4% (939/2509). Prevalence was higher in men than women (40.6% versus 33.5%; p < 0.001), and in all age groups, relative to children <5 years (12.2%; p < 0.001)). Prevalence increased with exposure time to the index case; relative to <6 h/week exposure, LTBI risk was greater for both ≥6 h/day (aOR = 2.0; 95% CI: 1.5-2.6) and <6 h/day but ≥6 h/week (aOR = 1.6; 95% CI: 1.1-2.2). Conclusions: The LTBI risk in immigrant contacts increases with recent exposure time to the index case, and may suggest recent LTBI in immigrants.

A Quasi-experimental Study on the Effect of Pre-entry Tuberculosis Screening for Immigrants on Treatment Outcomes in South Korea: A Difference-in-Differences Analysis

OBJECTIVE

This study ascertains the effects of the pre-entry tuberculosis (TB) screening policy, which was implemented as a strategy for managing TB among immigrants, on the treatment outcomes of immigrants in South Korea.

METHODS

This study linked three different datasets from 2013 to 2018, namely (1) Korean National Tuberculosis Surveillance System; (2) National Health Information Database for patients diagnosed with TB with ICD code A15-A19, B90, or U84.3; and (3) Statistics Korea database related to cause of deaths. To identify the effect of the policy, cohorts comprising Korean and immigrant TB patients notified before (January 1, 2013-December 31, 2015) and after (September 1, 2016-December 31, 2018), the implementations of the policy were established. A difference-in-differences (DID) analysis of the treatment success and mortality rates was performed.

RESULTS

Data from 100,262 TB patients were included in the analysis (before policy implementation: 1240 immigrants and 65,723 Koreans; after policy implementation: 256 immigrants and 33,043 Koreans). The propensity score matching-DID analysis results showed that the difference in the treatment success rate between immigrants and Koreans decreased significantly, from 16% before to 6% after the policy implementation. The difference in the mortality rate between the two groups decreased from - 3% before to - 1% after the policy implementation; however, this difference was insignificant.

CONCLUSION

The treatment outcomes of immigrant TB patients in South Korea improved after the implementation of the pre-entry active TB screening policy. Future immigrant TB policies should consider establishing active patient support strategies and a healthcare collaboration system between countries.

Comparable worth of life for all? Conducting and disseminating health economic evaluations for refugees in Germany

Comparative health economic evaluation is based on premise of being able to compare the worth of a year of life lived in full quality across different patients, population groups, settings and interventions. Given the rising numbers of forcibly displaced people, the nexus of economics, migration and health has emerged as a central theme in recent conceptual and empirical approaches. However, some of the assumptions made in conventional economic approaches do not hold true in the decision-making context of migration and the health of forcibly displaced populations. Using the experience of conducting and disseminating economic analyses to support decision-making on health screening policies for refugees in Germany, we show that in particular the assumptions of individual utility with no positive externalities, equity-blind utilitarian ethical stances and stable budgets are challenged. The further development of methods to address these challenges are required to support decision-makers in this contentious and politically fraught context and continue to make choices and decisions transparent.

Importance of Tuberculosis Screening of Resident Visa Applicants in Low TB Incidence Settings: Experience from Oman

Introduction

For Oman, a country targeting tuberculosis (TB) elimination, TB among expatriates is a major challenge. Thus, screening for active TB using chest X-ray was made mandatory for expatriates’ residency renewals.

Objective

To estimate the incidence of bacteriologically confirmed TB and assess impact of chest X-ray based TB screening among expatriates in Muscat Governorate.

Methods

Applicants for residency and renewals were mandated for chest X-ray-based TB screening in 2018. We collected data of screened subjects with radiological suspicion of TB who were subjected to further bacteriological evaluation.

Results

Of 501,290 applicants screened during the study period, 436 (0.09%) had X-ray findings suggestive of TB. Among the 436, TB was confirmed in 53 (12.2%; 95% CI 9.2–15.6), giving an overall prevalence of 10.6 (95% CI 8–13.9) per 100,000 applicants (number needed to be screened 9458). Among renewals, the point prevalence of TB was 10.5 per 100,000 expatriates screened (95% CI 6.9–14.04 per 100,000), with a mean follow-up period of 11.8 years.

Conclusion

Our findings are consistent with the recommendation for utilization of chest X-ray as a preferred tool for active case finding in the setting of expatriate screening. Our findings are also suggestive of the need for latent TB screening and ruling out TB prior to latent TB treatment.

A Retrospective Study of Non-Communicable Diseases amongst Blue-Collar Migrant Workers in Qatar

Background: South Asian workers have a greater predisposition to non-communicable diseases (NCDs) that is exacerbated by migration and length of residence in host countries. Aims: To examine the association between length of residence in Qatar with diagnosis of NCDs in male blue-collar workers. Methods: A retrospective investigation of the electronic health records (EHRs) of 119,581 clinical visits by 58,342 patients was conducted. Data included age, nationality and confirmed ICD-10 diagnosis. Based on duration of residence, the population was divided into groups: ≤6 months, 6–12 months, 1–≤2 years, 2–≤5 years, 5–≤6 years, >6 years. It was assumed that the group that had been resident in Qatar for ≤6 months represented diseases that had been acquired in their countries of origin. Results: South Asian (90%) patients presented with NCDs at a younger (mean ± SD age of 34.8 ± 9.0 years) age. Diabetes and hypertension were higher in those who had just arrived (<6 months’ group), compared to the other durations of residence groups. Conversely, acute respiratory infections, as well as dermatitis and eczema, all increased, perhaps a consequence of shared living/working facilities. Only patients with diabetes and hypertension visited the clinic multiple times, and the cost of medication for these NCDs was affordable, relative to earnings. Discussion/Conclusions: Blue-collar workers were predominantly South Asian, from lower socioeconomic classes, with early onset chronic NCDs. Notably, residence in Qatar gave them better access to affordable, significantly subsidized healthcare, leading to effective management of these chronic conditions.

Perspectives of Vietnamese, Sudanese and South Sudanese immigrants on targeting migrant communities for latent tuberculosis screening and treatment in low-incidence settings: A report on two Victorian community panels

BACKGROUND

Tuberculosis (TB) elimination strategies in Australia require a focus on groups who are at highest risk of TB infection, such as immigrants from high-burden settings. Understanding attitudes to different strategies for latent TB infection (LTBI) screening and treatment is an important element of justifiable elimination strategies.

METHOD

Two community panels were conducted in Melbourne with members of the Vietnamese (n = 11), Sudanese and South Sudanese communities (n = 9). Panellists were provided with expert information about LTBI and different screening and health communication strategies, then deliberated on how best to pursue TB elimination in Australia.

FINDINGS

Both panels unanimously preferred LTBI screening to occur pre-migration rather than in Australia. Participants were concerned that post-migration screening would reach fewer migrants, noted that conducting LTBI screening in Australia could stigmatize participants and that poor awareness of LTBI would hamper participation. If targeted screening was to occur in Australia, the Vietnamese panel preferred 'place-based' communication strategies, whereas the Sudanese and South Sudanese panel emphasized that community leaders should lead communication strategies to minimize stigma. Both groups emphasized the importance of maintaining community trust in Australian health service providers, and the need to ensure targeting did not undermine this trust.

CONCLUSION

Pre-migration screening was preferred. If post-migration screening is necessary, the potential for stigma should be reduced, benefit and risk profile clearly explained and culturally appropriate communication strategies employed. Cultural attitudes to health providers, personal health management and broader social vulnerabilities of targeted groups need to be considered in the design of screening programs.

Cost-effectiveness of targeted screening for active pulmonary tuberculosis among asylum-seekers: A modelling study with screening data from a German federal state (2002-2015)

Screening asylum-seekers for active pulmonary tuberculosis is common practice among many European countries with low incidence of tuberculosis. The reported yields vary substantially, partly due to the heterogeneous and dynamic nature of asylum-seeking populations. Rather than screening all new arrivals (indiscriminate screening), a few countries apply targeted screening based on incidence of tuberculosis in asylum-seekers' country of origin. However, evaluations of its cost-effectiveness have been scarce. The aim of this modelling study was to assess whether the introduction of a screening threshold based on the tuberculosis incidence in the country of origin is sensible from an economic perspective. To this end, we compare the current, indiscriminate screening policy for pulmonary tuberculosis in Germany with a hypothetical targeted screening programme using several potential screening thresholds based on WHO-reported incidence of tuberculosis in countries of origin. Screening data is taken from a large German federal state over 14 years (2002-2015). Incremental cost-effectiveness is measured as cost per case found and cost per case prevented. Our analysis shows that incremental cost-effectiveness ratios (ICERs) of screening asylum-seekers from countries with an incidence of 50 to 250/100,000 range between 15,000€ and 17,000€ per additional case found when compared to lower thresholds. The ICER for screening asylum-seekers from countries with an incidence <50/100,000 is 112,000€ per additional case found. Costs per case prevented show a similar increase in costs. The high cost per case found and per case prevented at the <50/100,000 threshold scenario suggests this threshold to be a sensible cut-off for targeted screening. Acknowledging that no screening measure can find all cases of tuberculosis, and that reactivation of latent infections makes up a large proportion of foreign-born cases, targeting asylum-seekers from countries with an incidence above 50/100,000 is likely to be a more reasonable screening measure for the prevention and control of tuberculosis than indiscriminate screening measures.

Tuberculosis in migrants - screening, surveillance and ethics

Tuberculosis (TB) is the leading infectious cause of human mortality and is responsible for nearly 2 million deaths every year. It is often regarded as a 'silent killer' because it predominantly affects the poor and marginalized, and disease outbreaks occur in 'slow motion' compared to Ebola or coronavirus 2 (COVID-19). In low incidence countries, TB is predominantly an imported disease and TB control in migrants is pivotal for countries to progress towards TB elimination in accordance with the World Health Organisations (WHO's) End TB strategy. This review provides a brief overview of the different screening approaches and surveillance processes that are in place in low TB incidence countries. It also includes a detailed discussion of the ethical issues related to TB screening of migrants in these settings and the different interests that need to be balanced. Given recognition that a holistic approach that recognizes and respects basic human rights is required to end TB, the review considers the complexities that require consideration in low-incidence countries that are aiming for TB elimination.