Screening for tuberculosis in migrants and visitors from high-incidence settings: present and future perspectives

Incidence of Tuberculosis Among Immigrants in Korea Who Participated in a Latent Tuberculosis Infection Screening Program

BACKGROUND

With a rapid decrease in tuberculosis (TB) incidence, the significance of latent tuberculosis infection (LTBI) has been underscored in South Korea. Although South Korea does not have a high proportion of immigrants compared to other countries, there is a growing argument that it should actively embrace immigrants as a solution to address issues of low birth rates and population aging. This study aimed to assess TB incidence among immigrants who participated a pilot LTBI screening program in South Korea.

METHODS

Records of immigrants participated in a pilot LTBI screening program in South Korea between 2018 and 2019 were linked with Korean National TB Surveillance System to determine TB development. Participants underwent interferon-gamma release assay (IGRA) and chest X-rays. Standardized incidence ratios (SIRs) stratified by age, country of origin's TB burden was calculated with a reference group of general South Korean population.

RESULTS

Of a total of 9,517 participants, 14 TB cases were identified. Participants with positive IGRA results who did not initiate LTBI treatment showed TB incidence of 312.5 per 100,000 person-years, whereas those with negative results showed TB incidence of 34.4 per 100,000 person-years, resulting in an incidence rate ratio of 9.08 (95% confidence interval [CI], 2.50-32.99). SIR of TB among total participants including those with negative IGRA results was 2.60 (95% CI, 1.54-4.38; P < 0.001), whereas SIR among those with positive IGRA results was 5.86 (95% CI, 3.15-10.89; P < 0.001). In the calculation of SIR among participants with positive IGRA results, those aged under 35 from high TB-burden countries or intermediate TB-burden countries showed a high SIR (18.08; 95% CI, 2.55-128.37; P = 0.004), and 11.30 (95% CI, 2.82-45.16; P < 0.001), respectively). Contrary to previous reports that suggest the majority of elderly population with a positive IGRA result were due to remote infection and had a lower TB risk compared to younger ages, SIR among those aged 65 or over from intermediate TB-burden countries was 6.15 (95% CI, 0.87-43.69; P = 0.069), which was comparable to that in younger participants aged between 35 and 49 (SIR, 4.87; 95% CI, 1.22-19.49; P = 0.025) or those aged between 50 and 64 (SIR, 4.62; 95% CI, 1.73-12.31; P = 0.002).

CONCLUSION

Young immigrants with positive IGRA results from countries with high or intermediate TB burden showed a relatively high TB risk compared to a general South Korea population. In addition, unexpected high TB risk was observed among elderly immigrants with positive IGRA results. In establishing future policies for LTBI in immigrants in South Korea, screenings should primarily focus on younger age group (who aged under 35). Additionally, further research is needed on the high TB risk observed in elderly immigrants.

Screening for latent tuberculosis in migrants-status quo and future challenges

OBJECTIVES

To review the evidence that migrants from tuberculosis (TB) high-incidence countries migrating to TB low-incidence countries significantly contribute to active TB cases in the counties of destination, primarily through reactivation of latent TB.

METHODS

This is a narrative review. The different screening programs in the countries of destination are reviewed either based on screening and preventive treatment of latent TB pre or more commonly - post arrival.

RESULTS

Screening can be performed using interferon-gamma release assays (IGRA) or tuberculin skin tests (TST). Preventive treatment of latent TB is using either monotherapy with isoniazid, or in combination with rifampicin or rifapentine. We discuss the ethical issues of preventive treatment in asymptomatic individuals and how these are addressed in different screening programs.

CONCLUSION

Screening migrants from TB high endemic countries to TB low endemic countries is beneficial. There is a lack of standardization and agreement on screening protocols, follow up and treatment.

Incidence of and Risk Factors for Active Tuberculosis Disease in Individuals With Glomerular Disease: A Canadian Cohort Study

RATIONALE & OBJECTIVE

Kidney failure is an established risk factor for active tuberculosis (TB) but the risk of TB has not been reported in specific kidney diseases. We sought to determine the incidence of and risk factors for active TB in patients with glomerular disease.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

A provincial kidney pathology registry (2000-2012) was used to identify 3,079 adult patients with IgA nephropathy, focal segmental glomerulosclerosis (FSGS), antineutrophil cytoplasmic antibody (ANCA)-related glomerulonephritis, lupus nephritis, membranous nephropathy, minimal change disease, or "other" glomerular diseases in British Columbia, Canada.

EXPOSURE

Predictors included demographics, immigration status, comorbidities, immunosuppression use, estimated glomerular filtration rate (eGFR), and proteinuria.

OUTCOME

A diagnosis of active TB was ascertained using administrative data linkages and defined based on (1) the dispensation of 1 or more unique combinations of medications used to treat active TB, or (2) physician or hospital visits for active TB.

ANALYTICAL APPROACH

The definition of TB was validated in an external cohort linked to the Provincial TB registry at the BC Centre for Disease Control (BCCDC). Standardized incidence ratios were calculated using the age-matched general population. Risk factors for active TB were identified using Cox proportional hazards regression analysis.

RESULTS

The sensitivity and specificity of the outcome definition of active TB were 87.6% and 99.5%, respectively. During a median follow-up of 6.2 years, 41 patients developed active TB with an incidence of 197 of 100,000 person-years, approximately 23 times as high as the general population and>6 times higher than the threshold of 30 per 100,000 used to define high TB incidence. A high incidence was observed in all glomerular diseases (range, 110-403 per 100,000), in both Canadian- and foreign-born patients (range, 124-424 per 100,000), and in patients exposed or not to immunosuppression (282 vs 147 per 100,000). Factors associated with higher TB risk included immigration from a high-incidence country (HR, 3.90 [95% CI, 1.75-8.68]), diminished eGFR (HR, 2.81 [95% CI, 1.18-6.69]), higher levels of proteinuria (HR, 1.15 [95% CI, 1.04-1.27]), lupus nephritis (HR, 2.79 [95% CI, 1.37-5.68]), and immunosuppression use (HR, 2.13 [95% CI, 1.13-4.03]).

LIMITATIONS

A relatively low number of events contributed to uncertainty in risk estimates.

CONCLUSIONS

Patients with glomerular disease have a high incidence of active TB irrespective of disease type, demographics, or use of immunosuppression. Prospective studies are needed to evaluate the utility of screening for latent TB infection in this population.

PLAIN-LANGUAGE SUMMARY

Patients with kidney failure are at high risk of developing tuberculosis (TB), a major infection that can be prevented by identifying and treating patients who have had prior exposure to TB. The risk of TB in specific kidney diseases is unknown. In this Canadian study of 3,079 patients with glomerular disease, a group of autoimmune kidney conditions, the rate of TB was 23 times higher than in the general population. The rate was high irrespective of the use of immunosuppressive drugs or whether patients had immigrated to Canada from another country. These findings suggest that screening patients with glomerular disease for prior TB exposure may be beneficial; however, this needs to be evaluated in a prospective study.

Tuberculosis in migrants: epidemiology, resistance and outcome in Milan, Italy

BACKGROUND

Human migration and the ever-changing geopolitical scenarios are redefining the epidemiology and the management of tuberculosis (TB), especially in low-TB burden countries welcoming high rates of people from high-TB burden countries.

METHODS

We conducted an observational retrospective mono-centric study in a Northern-Italy TB reference centre from 1 January 1990 to 31 December 2019, focusing on the differences in epidemiology, resistance patterns and treatment outcomes between Italians and migrants with active TB. Data were collected from medical records.

RESULTS

A total of 10555 patients were included, 4614 Italians and 5941 migrants. Among migrants, higher rates of rifampin-resistant (RR) or multidrug-resistant (MDR) TB were reported, as well as higher rates of loss to follow-up. Among Italians, higher mortality rates and a higher number of extrapulmonary TB cases were found.

CONCLUSION

Our study describes one of the largest cohorts of patients with active TB in Italy, highlighting the need for tailored approaches in native and migrant populations.

Tuberculosis related barriers and facilitators among immigrants in Atlantic Canada: A qualitative study

Tuberculosis (TB) is a disease caused by the bacterium Mycobacterium tuberculosis and affects approximately one-quarter of the world's population. Immigrant populations in Canada are disproportionately affected by TB. Canada's immigration medical examinations include screening for active TB but not latent TB infection (LTBI). In LTBI, the bacterium remains dormant within the host but can reactivate and cause disease. Once active, TB can be transmitted to close contacts sharing confined spaces leading to the possibility of outbreaks in the broader community. This study aimed to 1) assess the current TB knowledge, perceived risk, and risk behaviors of immigrants in Atlantic Canada as well as 2) identify barriers and facilitators to testing and treatment of TB among this population. Three focus group discussions were conducted with a total of 14 non-Canadian born residents of New Brunswick aged 19 years and older. Data were analyzed using inductive thematic analysis. Four themes were identified from the data relating to barriers to testing and treatment of LTBI: 1) Need for education, 2) stigma, 3) fear of testing, treatment, and healthcare system, and 4) complacency. Results included reasons individuals would not receive TB testing, treatment, or seek help, as well as facilitators to testing and treatment. These findings may inform the implemention of an LTBI screening program in Atlantic Canada and more broadly across the country.

Migration and medical screening for tuberculosis

Vulnerable populations, such as migrants and refugees, have an increased risk of tuberculosis disease, especially in the first years after arrival in the host country. The presence of migrants and refugees in Brazil exponentially grew over the period between 2011 and 2020, and approximately 1.3 million migrants from the Global South were estimated to be residing in Brazil, most of whom from Venezuela and Haiti. Tuberculosis control programs for migrants can be divided into pre- and post-migration screening strategies. Pre-migration screening aims to identify cases of tuberculosis infection (TBI) and can be carried out in the country of origin (pre-entry) or in the destination country (at entry). Pre-migration screening can also detect migrants at an increased risk of developing tuberculosis in the future. High-risk migrants are then followed up in post-migration screening. In Brazil, migrants are considered a priority group for the active search for tuberculosis cases. However, there is no recommendation or plan regarding screening for TBI in migrants and refugees. Ensuring prevention, diagnosis, and treatment for TBI and tuberculosis disease in migrant populations is an important aspect of tuberculosis control and elimination. In this review article, we address epidemiological aspects and access to health care for migrants in Brazil. In addition, the migration medical screening for tuberculosis was reviewed.

Complex Case Management of Mycobacterium Tuberculosis Extrapulmonary Manifestation to the Right Sacroiliac Joint

While Mycobacterium tuberculosis is a common bacterial pathogen that infects the respiratory system, especially in endemic regions, it may uncommonly manifest in other organ systems, such as the nervous, gastrointestinal, or musculoskeletal systems. Sacroiliac joint infections are rare, and only 1%-5% of all infections are tuberculous in nature. Given nonspecific inflammatory signs in both laboratory and radiologic examinations, early identification of the causative agent can be difficult. In this report, we present the case of a 29-year-old Eritrean woman who presented with an uncommon extrapulmonary tuberculosis manifestation of the right sacroiliac joint. The patient reported pain for two years before a formal diagnosis with multiple computed tomography scans demonstrated fluid collections about her right hip and thigh. The patient's medical history of developmental delay, psychosis, outdated medication documentation, non-therapeutic use of numerous psychiatric medications contraindicated for traditional anti-tubercular therapy, and socioeconomic history of a lack of social support and treatment arrangements with the patient's caregiver all complicated the treatment course. Given the rise in tuberculosis cases worldwide and vulnerability factors in patients with mental illnesses such as poverty, homelessness, diabetes, and HIV infection that can predispose patients to tuberculosis infections, early diagnosis and treatment are essential to reduce long-term consequences and improve clinical outcomes. Further research in the development of new tuberculosis treatment plans is essential to addressing an equitable treatment course alongside fighting against the recent rise in drug-resistant tuberculosis.

Prevalence of Tuberculosis and Mental Disorders Comorbidity: A Systematic Review and Meta-analysis

Persons with tuberculosis (TB) also often have a mental disorder (MD). We examined TB-MD comorbidity prevalence and its impact on TB treatment outcomes as reported in studies set in the United States or in the top five countries of origin (Mexico, the Philippines, India, Vietnam, and China) for non-US-born persons with TB. We searched MEDLINE, EMBASE, OVID, PsycINFO, CINAHL, and Scopus for articles published from database inception through September 2018. Of the 9 studies analyzed, one was set in the United States. The estimated pooled prevalence of comorbid TB-MD from eight non-US studies, with 2921 participants, was 34.0% [95% confidence interval (CI) 21.1%-49.5%]. Comorbid TB-MD prevalence varied by country in the studies evaluated. Additional research might elucidate the extent of TB-MD in the United States and the top five countries of origin.

Optimizing tuberculosis screening for immigrants in southern New Brunswick: A pilot study protocol

Introduction

Immigrants from high tuberculosis-burdened countries have been shown to have an increased risk of latent tuberculosis infection (LTBI). To reduce the risk of increased tuberculosis cases in Canada, the country has a comprehensive immigration medical examination process that identifies individuals with active tuberculosis using chest X-ray; however, it fails to identify LTBI. The lack of LTBI identification is concerning because immigrants with LTBI are at an increased risk of developing active tuberculosis within their first few years of migration due to stressful experiences common to many immigrants.

Objectives

The goal of this pilot study is to improve the current LTBI screening protocols among immigrants from high tuberculosis incidence countries and to better prevent and manage tuberculosis cases, by introducing an LTBI screening pilot program. The objectives are threefold: 1) to screen LTBI in immigrants from high tuberculosis incidence countries, including immigrants identified as being at risk of LTBI by the NB health care system, using the QuantiFERON-TB Gold Plus interferon-gamma release assay (IGRA); 2) to offer LTBI treatment and supports to those identified as having LTBI; and 3) to assess immigrant and health care providers (HCPs) satisfaction of the LTBI screening pilot program.

Methods

This cross-sectional study seeks to recruit 288 participants. Participants will be recruited via posters, social media platforms, invitations at immigrant wellness check-ups, presentations to local ethnocultural groups, and by snowball sampling. Consenting participants will be asked to submit a blood sample for LTBI screening; if positive, participants will be assessed and offered treatment for LTBI based on clinical assessment. Participants and HCPs’ feedback will be gathered via short questionnaires. For the quantitative portion of the study, descriptive statistics will be used to summarize participant characteristics and feedback. Simultaneous logistic regression will be performed to identify variables associated with the IGRA test outcome and evidence of increased CD8 T-cell immune response among those found to be LTBI-positive. Qualitative results will be analyzed using inductive thematic analysis.

Discussion

The findings from this study will allow us to understand the role of the IGRA LTBI screening assay and its feasibility and acceptability by immigrants and HCPs in New Brunswick. The findings will additionally provide information on the enhancers and barriers of LTBI screening and management useful in determining how best to expand the LTBI screening program if deemed appropriate.

Detecting Mycobacterium tuberculosis Infection in Children Migrating to Australia

In 2015, Australia updated premigration screening for tuberculosis (TB) disease in children 2-10 years of age to include testing for infection with Mycobacterium tuberculosis and enable detection of latent TB infection (LTBI). We analyzed TB screening results in children <15 years of age during November 2015-June 2017. We found 45,060 child applicants were tested with interferon-gamma release assay (IGRA) (57.7% of tests) or tuberculin skin test (TST) (42.3% of tests). A total of 21 cases of TB were diagnosed: 4 without IGRA or TST, 10 with positive IGRA or TST, and 7 with negative results. LTBI was detected in 3.3% (1,473/44,709) of children, for 30 applicants screened per LTBI case detected. LTBI-associated factors included increasing age, TB contact, origin from a higher TB prevalence region, and testing by TST. Detection of TB and LTBI benefit children, but the updated screening program's effect on TB in Australia is likely to be limited.

A systematic review and meta-analysis of mycobacterial infections in patients with idiopathic inflammatory myopathies

OBJECTIVES

Infections including tuberculosis (TB) are a leading cause of morbidity and mortality in idiopathic inflammatory myopathies (IIM). We systematically reviewed the prevalence of mycobacterial infections in patients with IIM.

METHODS

We screened PUBMED, EMBASE and SCOPUS databases and conference abstracts (2015-20) for original articles using Covidence. Pooled estimates of prevalence were calculated.

RESULTS

Of 83 studies (28 cohort studies, two case control and 53 case reports), 19 were analysed. Of 14 043 IIM patients, DM (54.41%) was the most common subset among TB. Most studies were from Asia with high prevalence (5.86%, 2.33%-10.60%). Pooled prevalence of mycobacterial infections among IIM was 3.58% (95% CI: 2.17%, 5.85%, P < 0.01). Disseminated and extrapulmonary forms (46.58%; 95% CI: 39.02%, 54.31%, P = 1.00) were as common as pulmonary TB (49.07%; 95% CI: 41.43%, 56.75%, P =0.99) both for I2=0. Muscle involvement, an otherwise rare site, was frequently seen in case reports (24.14%). M. tuberculosis (28.84%) was the most common pathogen followed by Mycobacterium avium complex (3.25%). Non-tuberculous mycobacteria were less common overall (6.25; 95% CI: 3.49%, 10.93%) I2=0, P =0.94. Subgroup analysis and meta-regression based on high vs low TB regions found prevalence 6.61% (2.96%, 11.33%) in high TB regions vs 2.05% (0.90%, 3.56%) in low TB regions. While death due to TB was occasionally reported (P =0.82), successful anti-tubercular treatment was common (13.95%).

CONCLUSION

TB is common in IIM, particularly in endemic regions though current data is largely heterogeneous. Extra-pulmonary forms and atypical sites including the muscle are frequent. Limited data suggests fair outcomes, although larger prospective studies may offer better understanding.

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.

Invited Commentary: The Role of Tuberculosis Screening Among Migrants to Low-Incidence Settings in (Not) Achieving Elimination

The cost-effectiveness of migrant tuberculosis prevention programs is highly relevant to many countries with low tuberculosis incidence as they attempt to eliminate the disease. Dale et al. (Am J Epidemiol. 2022;191(2):255-270) evaluated strategies for tuberculosis infection screening and treatment among new migrants to Australia. Screening for infection before migration, and then administering preventive treatment after arrival, was more cost-effective than performing both screening and treatment after arrival. From the Australian health payer perspective, the improved cost-effectiveness of premigration screening partly reflected the shift of screening costs to migrants, which may raise ethical concerns. Key sensitivity analyses highlighted the influence of health disutility associated with tuberculosis preventive treatment, and of posttreatment sequelae of tuberculosis disease. Both considerations warrant greater attention in future research. For all strategies, the impact on tuberculosis incidence among migrants was modest (<15%), suggesting enhanced migrant screening will not achieve tuberculosis elimination in low-incidence settings. This emphasizes the need to increase investment and effort in global tuberculosis prevention and care, which will ultimately reduce the prevalence of tuberculosis infection and therefore the risk of tuberculosis disease among migrants. Such efforts will benefit high and low tuberculosis incidence countries alike, and advance all countries further toward tuberculosis elimination.

Screening for Tuberculosis in Migrants: A Survey by the Global Tuberculosis Network

Tuberculosis (TB) does not respect borders, and migration confounds global TB control and elimination. Systematic screening of immigrants from TB high burden settings and-to a lesser degree TB infection (TBI)-is recommended in most countries with a low incidence of TB. The aim of the study was to evaluate the views of a diverse group of international health professionals on TB management among migrants. Participants expressed their level of agreement using a six-point Likert scale with different statements in an online survey available in English, French, Mandarin, Spanish, Portuguese and Russian. The survey consisted of eight sections, covering TB and TBI screening and treatment in migrants. A total of 1055 respondents from 80 countries and territories participated between November 2019 and April 2020. The largest professional groups were pulmonologists (16.8%), other clinicians (30.4%), and nurses (11.8%). Participants generally supported infection control and TB surveillance established practices (administrative interventions, personal protection, etc.), while they disagreed on how to diagnose and manage both TB and TBI, particularly on which TBI regimens to use and when patients should be hospitalised. The results of this first knowledge, attitude and practice study on TB screening and treatment in migrants will inform public health policy and educational resources.

Paediatric management of a tuberculosis outbreak in an Irish Direct Provision Centre

Direct Provision in Ireland provides basic needs of food and shelter to asylum seekers while their refugee status is processed. There are a number of issues associated with living conditions in these centres including overcrowding, nutrition and play facilities (1,2). This article outlines the protocol of contact tracing and management of latent tuberculosis infection in the paediatric setting after a confirmed adult case of tuberculosis within a Direct Provision centre in Ireland. This is a retrospective case series of 82 children living in the centre. Twenty-two children were deemed at risk of infection, all asymptomatic. Sixteen children (20%) were treated for possible latent tuberculosis infection with isoniazid for 6-9 months; compliance was good with no side effects reported. This article highlights the risk to vulnerable populations, especially children, when residing in Direct Provision facilities. Initial migrant screening on entry is essential, in addition to improving living conditions and time spent by families in this living environment.

Fewer losses in the cascade of care for latent tuberculosis with solo interferon-gamma release assay screening compared to sequential screening

Background

Refugees are at increased risk of developing tuberculosis (TB) soon after resettlement. Targeting high-risk populations for latent tuberculosis infection (LTBI) screening and treatment is an important measure towards eliminating TB in low incidence countries, however, there are low rates of screening and treatment completion in the LTBI cascade of care. The authors hypothesized that an interferon-gamma release assay (IGRA) screening strategy would lead to a higher proportion of refugees completing LTBI screening and treatment, compared to sequential screening with tuberculin skin test (TST) and confirmatory IGRA.

Methods

This retrospective cohort study included eligible refugees screened with a sequential strategy versus a solo-IGRA strategy at different time periods from a centralized refugee clinic. The primary outcome was the proportion completing LTBI screening in each cohort.

Results

A total of 471 subjects were included (240 in sequential screening, 231 in solo-IGRA screening). 54% of refugees completed LTBI screening with sequential testing, compared to 85% of those screened with a solo-IGRA. Time to completing screening was also shorter in the solo-QFT group (difference 16.5 days, p < 0.01, 95% confidence interval 9.3, 23.7). There was a higher incidence of LTBI diagnosis in the solo-IGRA group (41 versus 20, p = 0.002). Screening completion was predicted by solo-IGRA screening (aOR 3.74, 95% confidence interval 2.30, 6.09; p < 0.001) and if refugees were privately-sponsored (aOR 2.81, 95% confidence interval 1.53, 5.15; p = 0.001). Treatment completion rates did not differ between groups.

Conclusion

This study has identified fewer dropouts in the LTBI cascade of care if a solo-IGRA strategy is used for screening. An IGRA should be strongly considered as the screening method for refugees arriving in low-incidence settings if resources are available.

Initiation and completion of treatment for latent tuberculosis infection in migrants globally: a systematic review and meta-analysis

Background

Latent tuberculosis infection (LTBI) is one of the most prevalent infections globally and can lead to the development of active tuberculosis disease. In many low-burden countries, LTBI is concentrated within migrant populations often because of a higher disease burden in the migrant's country of origin. National programmes consequently focus on screening and treating LTBI in migrants to prevent future tuberculosis cases; however, how effective these programmes are is unclear. We aimed to assess LTBI treatment initiation and outcomes among migrants, and the factors that influence both.

Methods

For this systematic review and meta-analysis, we searched Embase, MEDLINE, and Global Health, and manually searched grey literature from Jan 1, 2000, to April 21, 2020. We included primary research articles reporting on LTBI treatment initiation or completion, or both, in migrants and excluded articles in which data were not stratified by migrant status, or in which the data were related to outcomes before 2000. There were no geographical or language restrictions. All included studies were quality appraised using recognised tools depending on their design, and we assessed the heterogeneity of analyses using I². We extracted data on the numbers of migrants initiating and completing treatment. Our primary outcomes were LTBI treatment initiation and completion in migrants (defined as foreign-born). We used random-effects meta-regression to examine the influence of factors related to these outcomes. The study is registered with PROSPERO (CRD42019140338).

Findings

2199 publications were retrieved screened, after which 39 publications from 13 mostly high-income, low-burden countries were included in our analyses, with treatment initiation and completion data reported for 31 598 migrants positive for LTBI, with not all articles reporting the full pathway from initiation to completion. The pooled estimate for the true proportion of migrants testing positive who initiated treatment was 69% (95% CI 51–84; I²= 99·62%; 4409 of 8764). The pooled estimate for the true proportion of migrants on treatment in datasets, who subsequently completed it was 74% (95% CI = 66–81; I²= 99·19%; 15 516 of 25 629). Where data were provided for the entire treatment pathway, the pooled estimate for the true proportion of migrants who initiated and completed treatment after a positive test was only 52% (95% CI 40–64; I²= 98·90%; 3289 of 6652). Meta-regression showed that LTBI programmes are improving, with more recent reported data (2010–20) associated with better rates of treatment initiation and completion, with multiple complex factors affecting treatment outcomes in migrants.

Interpretation

Although our analysis highlights that LTBI treatment initiation and completion in migrants has improved considerably from 2010–20, there is still room for improvement, with drop out reported along the entire treatment pathway. The delivery of these screening and treatment programmes will require further strengthening if the targets to eradicate tuberculosis in low-incidence countries are to be met, with greater focus needed on engaging migrants more effectively in the clinic and understanding the diverse and unique barriers and facilitators to migrants initiating and completing treatment.

Funding

European Society of Clinical Microbiology and Infectious Diseases, the Rosetrees Trust, the National Institute for Health Research, and the Academy of Medical Sciences.

Factors associated with latent tuberculosis among international migrants in Brazil: a cross-sectional study (2020)

BACKGROUND

Migrants are a high priority group for TB control measures due to their high exposure to risk factors such as poverty and social vulnerability. The study aimed to identify factors associated with latent TB among international migrants living in four Brazilian state capitals. This was a cross-sectional study conducted in September and October 2020 in a sample of 903 international migrants living in four Brazilian state capitals: Boa Vista/RR (458), Manaus/AM (136), São Paulo/SP (257), and Curitiba/PR (52). Data were collected with a questionnaire consisting of open and closed questions on personal characteristics, information on TB, and use of preventive measures. Tuberculin skin test (TST) was performed, with reading after 72 h by trained nurses and using 5 mm induration as the positive cutoff. Chi-square test (X2) and Fisher's exact test, both two-tailed, were used to compare statistically significant levels of association between the migrants´ sociodemographic characteristics, vulnerability, and latent TB infection (LTBI). Binary logistic regression was applied to calculate odds ratios and respective 95% confidence intervals. For all the tests, type I error of 5% was defined as statistically significant (p < 0.05).

RESULTS

Prevalence of LTBI among migrants was 46.1% in Manaus/AM, 33.3% in São Paulo/SP, 28.1% in Curitiba/PR, and 23.5% in Boa Vista/RR. Factors associated with latent infection were age, male gender, and brown or indigenous race.

CONCLUSIONS

The study showed high prevalence of latent TB among international migrants.

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.

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.

Insights into culturally appropriate latent tuberculosis infection (LTBI) screening in NSW: perspectives of Indian and Pakistani migrants

OBJECTIVE

Latent tuberculosis (LTBI) case-finding and treatment are a focus of TB elimination in Australia. We sought the perspectives of migrants from two high-burden countries likely to be targeted by this strategy.

METHODS

To understand perceptions of migrant groups in Australia on LTBI screening, 28 in-depth interviews were conducted with Indian and Pakistani community members recruited purposively through local organisations in the Illawarra region, New South Wales. Drawing on local TB policy, data collected qualitatively was analysed using framework methodologies.

RESULTS

Australia's immigration system prioritises migrants of higher socioeconomic status. Participants supported elimination but perceived TB as a disease of the poor and not relevant to them. Lack of understanding of LTBI and sensitivity to being 'targeted' are further barriers to screening participation.

CONCLUSION

Information provision and targeting rationale are an essential preamble to LTBI screening. Migration appears to modify cultural attitudes to TB, but not significantly. Despite less stigma surrounding TB in Australian contexts, testing privacy and confidentiality, and limiting public identification of specific groups remain important to program acceptability. Implications for public health: Progress towards TB elimination can be enhanced by consulting with targeted communities, using existing networks for communication and service provision; emphasising prevention benefits.

Migration Health: Highlights from Inaugural International Society of Travel Medicine (ISTM) Conference on Migration Health

PURPOSE OF REVIEW

International migration is a global phenomenon that is growing in scope, complexity and impact. The inaugural International Society of Travel Medicine (ISTM) International Conference on Migration Health provided a forum to discuss scientific evidence on the broad issues relevant to migration health. This review summarises the key health issues, with a focus on infectious diseases, current effective strategies and future considerations presented at this forum and in the recent literature.

RECENT FINDINGS

Migrants face health disparities for both communicable and non-communicable diseases. Their heightened infectious disease risks, compared to host populations, are related to pre-migration exposures, the circumstances of the migration journey and the receptivity and access to health services in their receiving countries. While the prevalence of infectious diseases identified through screening programmes are generally low, delays in diagnosis and treatment for a range of treatable infectious diseases result in higher morbidity and mortality among migrants. Barriers to care in host countries occur at the patient, provider and health systems levels. Coordinated and inclusive health services, healthcare systems and health policies, responsive to patient diversity reduce these barriers. Structural barriers to healthcare provision impede equitable care to migrants and refugees. Public health and medical professionals have a role in advocating for policy reforms.

Latent tuberculosis screening and treatment among asylum seekers: a mixed-methods study

Introduction

Evidence on conditions for implementation of latent tuberculosis infection (LTBI) screening and treatment among asylum seekers is needed to inform tuberculosis (TB) control policies. We used mixed-methods to evaluate the implementation of an LTBI screening and treatment programme among asylum seekers in the Netherlands.

Methods

We offered voluntary LTBI screening to asylum seekers aged ≥12 years living in asylum seeker centres from countries with a TB incidence >200 per 10 000 population. We calculated LTBI screening and treatment cascade coverage, and assessed associated factors with Poisson regression using robust variance estimators. We interviewed TB care staff (seven group interviews) and Eritrean clients (21 group and 21 individual interviews) to identify programme enhancers and barriers.

Results

We screened 719 (63% of 1136) clients for LTBI. LTBI was diagnosed among 178 (25%) clients; 149 (84%) initiated LTBI treatment, of whom 129 (87%) completed treatment. In-person TB and LTBI education, the use of professional interpreters, and collaboration with partner organisations were enhancers for LTBI screening uptake. Demand-driven LTBI treatment support by TB nurses enhanced treatment completion. Factors complicating LTBI screening and treatment were having to travel to public health services, language barriers and moving from asylum seeker centres to the community during treatment.

Conclusion

LTBI screening and treatment of asylum seekers is feasible and effective when high quality of care is provided, including culture-sensitive TB education throughout the care cascade. Additionally, collaboration with partner organisations, such as agencies responsible for reception and support of asylum seekers, should be in place.

Detailed characterisation of the tuberculosis epidemic in Western Sydney: a descriptive epidemiological study

Traditional tuberculosis (TB) epidemiology reports rarely provide a detailed analysis of TB incidence in particular geographic locations and among diverse population groups. Western Sydney Local Health District (WSLHD) has one of the highest TB incidence rates in Australia, and we explored whether more detailed epidemiological analysis could provide a better overview of the local disease dynamics.

Using multiple relevant data sources, we performed a retrospective descriptive study of TB cases diagnosed within the WSLHD from 2006 to 2015 with a specific focus on geographic hotspots and the population structure within these hotspots.

Over the study period nearly 90% of Western Sydney TB cases were born in a high TB incidence country. The TB disease burden was geographically concentrated in particular areas, with variable ethnic profiles in these different hotspots. The most common countries of birth were India (33.0%), the Philippines (11.4%) and China (8.8%). Among the local government areas in Western Sydney, Auburn had the highest average TB incidence (29.4 per 100 000) with exceptionally high population-specific TB incidence rates among people born in Nepal (average 223 per 100 000 population), Afghanistan (average 154 per 100 000 population) and India (average 143 per 100 000 population).

Similar to other highly cosmopolitan cities around the world, the TB burden in Sydney showed strong geographic concentration. Detailed analysis of TB patient and population profiles in Western Sydney should guide better contextualised and culturally appropriate public health strategies.

High migration from tuberculosis (TB)-endemic settings to Western Sydney is driving over-representation among TB cases of specific cultural groups within geographic “hotspots”, requiring contextualised and culturally appropriate public health strategieshttp://bit.ly/2LqusU9

Effectiveness of interventions for reducing TB incidence in countries with low TB incidence: a systematic review of reviews

AIMS

What is the evidence base for the effectiveness of interventions to reduce tuberculosis (TB) incidence in countries which have low TB incidence?

METHODS

We conducted a systematic review of interventions for TB control and prevention relevant to low TB incidence settings (<10 cases per 100 000 population). Our analysis was stratified according to "direct" or "indirect" effects on TB incidence. Review quality was assessed using AMSTAR2 criteria. We summarised the strength of review level evidence for interventions as "sufficient", "tentative", "insufficient" or "no" using a framework based on the consistency of evidence within and between reviews.

RESULTS

We found sufficient review level evidence for direct effects on TB incidence/case prevention of vaccination and treatment of latent TB infection. We also found sufficient evidence of beneficial indirect effects attributable to drug susceptibility testing and adverse indirect effects (measured as sub-optimal treatment outcomes) in relation to use of standardised first-line drug regimens for isoniazid-resistant TB and intermittent dosing regimens. We found insufficient review level evidence for direct or indirect effects of interventions in other areas, including screening, adherence, multidrug-resistant TB, and healthcare-associated infection.

DISCUSSION

Our review has shown a need for stronger evidence to support expert opinion and country experience when formulating TB control policy.

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

OBJECTIVE

To compare predeparture tuberculosis (TB) screening policies, including screening criteria and screening tests, and visa requirements for prospective migrants to high-income countries that have low to intermediate TB incidence and high immigration.

STUDY DESIGN

Systematic review of policy documents.

METHODS

We systematically identified high-income, high net-migration countries with an estimated TB incidence of <30 per 100,000. After initial selection, this yielded 15 countries which potentially had TB screening policies. We performed a systematic search of governmental and official visa services' websites for these countries to identify visa information and policy documents for prospective migrants. Results were summarized, tabulated, and compared.

RESULTS

Programs to screen for active TB were identified in all 15 countries, but screening criteria and screening tests varied substantially between countries. Prospective migrants' country of origin represented an initial assessment criterion which generally focused on elevated TB incidence based on World Health Organization data but also focused on the countries of origin that sent the most migrants, and this varied between destination countries. Specific categories of migrants represented a second assessment criterion that focused on duration of stay and reasons for migration; the focus of which showed variation between the destination countries. Specific screening tests including medical examination and chest X-rays were used as the final stage of assessment, and there were differences between which tests were used between the destination countries.

CONCLUSIONS

Current approaches to migrant TB screening are inconsistent in their approach and implementation. While this variation might reflect adaptation to local public health situations, it could also indicate uncertainty concerning optimal strategies. Comparative research studies are needed to define the most effective and efficient methods for TB screening of migrants.

Practical challenges and solutions to TB control in a lower-middle-income country: experiences from Mongolia

The challenges of tuberculosis (TB) control vary significantly between countries with a low and high incidence of TB. A major focus of TB control efforts in countries with a low incidence of TB is on treatment of latent TB infection in high-risk groups [1] including contacts of patients with active TB [2], patients with medical conditions that increase the risk of TB reactivation [3–5] and migrants from settings with a high incidence of TB [6, 7].

Operational research, community initiatives and NGOs play an important role in improving TB care in low- and middle-income countrieshttp://ow.ly/wpjO30kA3fu