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Saleem UA, Karimi AS, Ehsan H. A Systematic Review on Pulmonary TB Burden and Associated Factors Among Immigrants in the UK. Infect Drug Resist 2023; 16:7835-7853. [PMID: 38162319 PMCID: PMC10757787 DOI: 10.2147/idr.s441536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/14/2023] [Indexed: 01/03/2024] Open
Abstract
Background The rapid growth of international human migration has positioned the UK in the top five countries in the world with 9.4 million immigrants in 2022. These immigrants originate from low- and middle-income countries and remain particularly at risk of developing TB. In the UK, the number of TB cases has been increasing, and the influx of immigrants could be a contributing factor. Objective This review aims to map the burden of pulmonary TB among immigrants in the UK and investigate associated factors. It also reviews the TB management approaches among immigrants in the UK. Design The study utilized PRISMA guidelines to search electronic databases (PubMed and EMBASE) for articles published from 2000 to 2022 on TB prevalence and factors in immigrants and explored government websites for TB management strategies. Results Nineteen out of 530 initially identified articles were included. The included studies reported a prevalence rate of TB among immigrants ranging from 0.04 to 52.1%, showing a decrease in the burden over time. Additionally, a higher number of TB cases were observed among immigrants from the Asian region, particularly immigrants from South Asia, followed by those from sub-Saharan Africa. Stigma, misconception about the disease, language barrier, lack of confidentiality, and unfriendly healthcare system for immigrants were the main drivers of the TB burden among immigrants. The TB management approaches in the UK include pre-entry screening for active TB, LTBI testing for a specific population group, and antibacterial therapy for 3-6 months for TB patients. Conclusion The UK's control and prevention efforts in reducing tuberculosis prevalence among immigrants show optimism, but challenges persist. Key improvements include healthcare delivery, TB improvement programs, and policies addressing stigma and patient confidentiality.
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Affiliation(s)
- Uzair Ahmad Saleem
- Faculty of Health, Medicine & Life Sciences, University of Maastricht, Maastricht, the Netherlands
| | - Ali Sina Karimi
- Medical Sciences Research Center, Ghalib University, Kabul, Afghanistan
| | - Hedayatullah Ehsan
- Medical Sciences Research Center, Ghalib University, Kabul, Afghanistan
- Kabul University of Medical Sciences, Kabul, Afghanistan
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2
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O'Connell J, de Barra E, McConkey S. Systematic review of latent tuberculosis infection research to inform programmatic management in Ireland. Ir J Med Sci 2021; 191:1485-1504. [PMID: 34595689 PMCID: PMC9308571 DOI: 10.1007/s11845-021-02779-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 09/08/2021] [Indexed: 11/11/2022]
Abstract
The World Health Organisation (WHO) End Tuberculosis (TB) Strategy and the WHO Framework Towards Tuberculosis Elimination in Low Incidence Countries state that latent tuberculosis infection (LTBI) screening and treatment in selected high-risk groups is a priority action to eliminate TB. The European Centre for Disease Prevention and Control (ECDC) advises that this should be done through high-quality programmatic management, which they describe as having six key components. The research aim was to systematically review the literature to identify what is known about the epidemiology of LTBI and the uptake and completion of LTBI screening and treatment in Ireland to inform the programmatic management of LTBI nationally. A systematic literature review was performed according to a review protocol and reported in adherence with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Twenty-eight studies were eligible for inclusion and described LTBI screening or treatment performed in one of five contexts, pre-biologic or other immunosuppression screening, people living with HIV, TB case contacts, other vulnerable populations, or healthcare workers. The risk of bias across studies with regard to prevalence of LTBI was generally high. One study reported a complete cascade of LTBI care from screening initiation to treatment completion. This systematic review has described what published research there is on the epidemiology and cascade of LTBI care in Ireland and identified knowledge gaps. A strategy for addressing these knowledge gaps has been proposed.
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Affiliation(s)
- James O'Connell
- School of Postgraduate Studies, Royal College of Surgeons in Ireland, Dublin 2, Dublin, Ireland.
| | - Eoghan de Barra
- Department of International Health and Tropical Medicine, Royal College of Surgeons in Ireland, Dublin 2, Dublin, Ireland.,Department of Infectious Diseases Medicine, Beaumont University Hospital, Dublin 5, Dublin, Ireland
| | - Samuel McConkey
- Department of International Health and Tropical Medicine, Royal College of Surgeons in Ireland, Dublin 2, Dublin, Ireland.,Department of Infectious Diseases Medicine, Beaumont University Hospital, Dublin 5, Dublin, Ireland
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3
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Dale KD, Karmakar M, Snow KJ, Menzies D, Trauer JM, Denholm JT. Quantifying the rates of late reactivation tuberculosis: a systematic review. THE LANCET. INFECTIOUS DISEASES 2021; 21:e303-e317. [PMID: 33891908 DOI: 10.1016/s1473-3099(20)30728-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 08/12/2020] [Accepted: 08/29/2020] [Indexed: 11/17/2022]
Abstract
The risk of tuberculosis is greatest soon after infection, but Mycobacterium tuberculosis can remain in the body latently, and individuals can develop disease in the future, sometimes years later. However, there is uncertainty about how often reactivation of latent tuberculosis infection (LTBI) occurs. We searched eight databases (inception to June 25, 2019) to identify studies that quantified tuberculosis reactivation rates occurring more than 2 years after infection (late reactivation), with a focus on identifying untreated study cohorts with defined timing of LTBI acquisition (PROSPERO registered: CRD42017070594). We included 110 studies, divided into four methodological groups. Group 1 included studies that documented late reactivation rates from conversion (n=14) and group 2 documented late reactivation rates in LTBI cohorts from exposure (n=11). Group 3 included 86 studies in LTBI cohorts with an unknown exposure history, and group 4 included seven ecological studies. Since antibiotics have been used to treat tuberculosis, only 11 studies have documented late reactivation rates in infected, untreated cohorts from either conversion (group 1) or exposure (group 2); six of these studies lasted at least 4 years and none lasted longer than 10 years. These studies found that tuberculosis rates declined over time, reaching approximately 200 cases per 100 000 person-years or less by the fifth year, and possibly declining further after 5 years but interpretation was limited by decreasing or unspecified cohort sizes. In cohorts with latent tuberculosis and an unknown exposure history (group 3), tuberculosis rates were generally lower than those seen in groups 1 and 2, and beyond 10 years after screening, rates had declined to less than 100 per 100 000 person-years. Reinfection risks limit interpretation in all studies and the effect of age is unclear. Late reactivation rates are commonly estimated or modelled to prioritise tuberculosis control strategies towards tubuculosis elimination, but significant gaps remain in our understanding that must be acknowledged; the relative importance of late reactivation versus early progression to the global burden of tuberculosis remains unknown.
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Affiliation(s)
- Katie D Dale
- Victorian Tuberculosis Program, Royal Melbourne Hospital, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia; Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia.
| | - Malancha Karmakar
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia; Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kathryn J Snow
- Centre for International Child Health, Department of Paediatrics, Royal Children's Hospital, University of Melbourne, Parkville, VIC, Australia; Australia Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
| | - Dick Menzies
- Respiratory Epidemiology and Clinical Research Unit, McGill International TB Centre, Montreal, QC, Canada
| | - James M Trauer
- Victorian Tuberculosis Program, Royal Melbourne Hospital, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia; School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Justin T Denholm
- Victorian Tuberculosis Program, Royal Melbourne Hospital, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia; Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
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4
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Delacourt C, Guerin S, Pommelet V. [Interferon gamma release assay tests in children less than 15 years old]. Rev Mal Respir 2018; 35:875-878. [PMID: 30224212 DOI: 10.1016/j.rmr.2018.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 03/21/2018] [Indexed: 11/15/2022]
Affiliation(s)
- C Delacourt
- Hôpital Necker-Enfants-Malades, AP-HP, 75015 Paris, France.
| | - S Guerin
- Hôpital Necker-Enfants-Malades, AP-HP, 75015 Paris, France
| | - V Pommelet
- Service de pédiatrie générale, hôpital Robert-Debré, AP-HP, 75019 Paris, France
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5
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Antoun F, Charlois-Ou C. [Interferon-gamma release assay tests in migrants]. Rev Mal Respir 2018; 35:872-874. [PMID: 30217575 DOI: 10.1016/j.rmr.2018.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 03/21/2018] [Indexed: 10/28/2022]
Affiliation(s)
- F Antoun
- Centre de lutte anti-tuberculeuse, direction de l'action sociale de l'enfance et de la santé, département de Paris, 75013 Paris, France.
| | - C Charlois-Ou
- Centre de lutte anti-tuberculeuse, direction de l'action sociale de l'enfance et de la santé, département de Paris, 75013 Paris, France
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6
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Hayward S, Harding RM, McShane H, Tanner R. Factors influencing the higher incidence of tuberculosis among migrants and ethnic minorities in the UK. F1000Res 2018; 7:461. [PMID: 30210785 PMCID: PMC6107974 DOI: 10.12688/f1000research.14476.2] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/09/2018] [Indexed: 12/17/2022] Open
Abstract
Migrants and ethnic minorities in the UK have higher rates of tuberculosis (TB) compared with the general population. Historically, much of the disparity in incidence between UK-born and migrant populations has been attributed to differential pathogen exposure, due to migration from high-incidence regions and the transnational connections maintained with TB endemic countries of birth or ethnic origin. However, focusing solely on exposure fails to address the relatively high rates of progression to active disease observed in some populations of latently infected individuals. A range of factors that disproportionately affect migrants and ethnic minorities, including genetic susceptibility, vitamin D deficiency and co-morbidities such as diabetes mellitus and HIV, also increase vulnerability to infection with
Mycobacterium tuberculosis (M.tb) or reactivation of latent infection. Furthermore, ethnic socio-economic disparities and the experience of migration itself may contribute to differences in TB incidence, as well as cultural and structural barriers to accessing healthcare. In this review, we discuss both biological and anthropological influences relating to risk of pathogen exposure, vulnerability to infection or development of active disease, and access to treatment for migrant and ethnic minorities in the UK.
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Affiliation(s)
- Sally Hayward
- St John's College, University of Oxford, Oxford, OX1 3JP, UK
| | | | - Helen McShane
- The Jenner Institute, University of Oxford, Oxford, OX1 3PS, UK
| | - Rachel Tanner
- The Jenner Institute, University of Oxford, Oxford, OX1 3PS, UK
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7
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Hayward S, Harding RM, McShane H, Tanner R. Factors influencing the higher incidence of tuberculosis among migrants and ethnic minorities in the UK. F1000Res 2018; 7:461. [PMID: 30210785 PMCID: PMC6107974 DOI: 10.12688/f1000research.14476.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/09/2018] [Indexed: 09/04/2023] Open
Abstract
Migrants and ethnic minorities in the UK have higher rates of tuberculosis (TB) compared with the general population. Historically, much of the disparity in incidence between UK-born and migrant populations has been attributed to differential pathogen exposure, due to migration from high-incidence regions and the transnational connections maintained with TB endemic countries of birth or ethnic origin. However, focusing solely on exposure fails to address the relatively high rates of progression to active disease observed in some populations of latently infected individuals. A range of factors that disproportionately affect migrants and ethnic minorities, including genetic susceptibility, vitamin D deficiency and co-morbidities such as diabetes mellitus and HIV, also increase vulnerability to infection with Mycobacterium tuberculosis (M.tb) or reactivation of latent infection. Furthermore, ethnic socio-economic disparities and the experience of migration itself may contribute to differences in TB incidence, as well as cultural and structural barriers to accessing healthcare. In this review, we discuss both biological and anthropological influences relating to risk of pathogen exposure, vulnerability to infection or development of active disease, and access to treatment for migrant and ethnic minorities in the UK.
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Affiliation(s)
- Sally Hayward
- St John’s College, University of Oxford, Oxford, OX1 3JP, UK
| | | | - Helen McShane
- The Jenner Institute, University of Oxford, Oxford, OX1 3PS, UK
| | - Rachel Tanner
- The Jenner Institute, University of Oxford, Oxford, OX1 3PS, UK
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8
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Zenner D, Loutet MG, Harris R, Wilson S, Ormerod LP. Evaluating 17 years of latent tuberculosis infection screening in north-west England: a retrospective cohort study of reactivation. Eur Respir J 2017; 50:50/1/1602505. [PMID: 28751410 PMCID: PMC5540676 DOI: 10.1183/13993003.02505-2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/20/2017] [Indexed: 11/17/2022]
Abstract
Approximately 72% of tuberculosis (TB) cases in England occur among non-UK born individuals, mostly as a result of reactivation of latent TB infection (LTBI). Programmatic LTBI screening is a key intervention of the TB strategy for England. This article reviews the results of a long-standing LTBI screening initiative in England. A retrospective cohort was created through probabilistic linkage between LTBI screening data and national TB case notifications. Screened persons were followed until they died, became a case, emigrated or until cohort-end. TB incidence rates and rate ratios (IRR) were calculated. 97 out of 1820 individuals screened for LTBI were reported to have active TB. Crude incidence rates among LTBI-positive, treatment-naïve individuals were 4.1 and 2.3 per 100 person-years in the QuantiFERON and tuberculin skin test cohorts, respectively. Among the QuantiFERON cohort, Poisson regression showed that LTBI positivity (IRR 22.6, 95% CI 6.8–74.6) and no chemoprophylaxis increased the probability of becoming a TB case (IRR 0.17, 95% CI 0.05–0.6). We found high TB rates in LTBI-positive, treatment-naïve individuals and a strong association between no treatment and becoming a TB case, demonstrating feasibility and effectiveness of LTBI screening and providing important policy lessons for LTBI screening in England and beyond. Screening follow-up showed high TB rates in LTBI-positive, treatment-naïve individuals and treatment protectionhttp://ow.ly/IUaW30bggkH
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Affiliation(s)
- Dominik Zenner
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK .,Institute for Global Health, University College London, London, UK.,National Institute for Health Research Health Protection Research Unit in Respiratory Infections, Imperial College London, London, UK
| | - Miranda G Loutet
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK
| | - Ross Harris
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK
| | - Stephen Wilson
- Dept of Respiratory and General Medicine, East Lancashire Hospitals NHS Trust, Blackburn, UK
| | - L Peter Ormerod
- Institute of Inflammation, University of Manchester, Manchester, UK.,Lancashire Postgraduate School of Medicine and Health, University of Central Lancashire, Preston, UK
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9
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Pareek M, Greenaway C, Noori T, Munoz J, Zenner D. The impact of migration on tuberculosis epidemiology and control in high-income countries: a review. BMC Med 2016; 14:48. [PMID: 27004556 PMCID: PMC4804514 DOI: 10.1186/s12916-016-0595-5] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 03/08/2016] [Indexed: 02/08/2023] Open
Abstract
Tuberculosis (TB) causes significant morbidity and mortality in high-income countries with foreign-born individuals bearing a disproportionate burden of the overall TB case burden in these countries. In this review of tuberculosis and migration we discuss the impact of migration on the epidemiology of TB in low burden countries, describe the various screening strategies to address this issue, review the yield and cost-effectiveness of these programs and describe the gaps in knowledge as well as possible future solutions.The reasons for the TB burden in the migrant population are likely to be the reactivation of remotely-acquired latent tuberculosis infection (LTBI) following migration from low/intermediate-income high TB burden settings to high-income, low TB burden countries.TB control in high-income countries has historically focused on the early identification and treatment of active TB with accompanying contact-tracing. In the face of the TB case-load in migrant populations, however, there is ongoing discussion about how best to identify TB in migrant populations. In general, countries have generally focused on two methods: identification of active TB (either at/post-arrival or increasingly pre-arrival in countries of origin) and secondly, conditionally supported by WHO guidance, through identifying LTBI in migrants from high TB burden countries. Although health-economic analyses have shown that TB control in high income settings would benefit from providing targeted LTBI screening and treatment to certain migrants from high TB burden countries, implementation issues and barriers such as sub-optimal treatment completion will need to be addressed to ensure program efficacy.
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Affiliation(s)
- Manish Pareek
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK. .,Department of Infection and HIV Medicine, University Hospitals of Leicester NHS Trust, Leicester, UK.
| | - Christina Greenaway
- Division of Infectious Diseases and Department of Clinical Epidemiology, Jewish General Hospital, McGill University, Montreal, Canada
| | - Teymur Noori
- European Centre for Disease Prevention and Control, Solna, Sweden
| | - Jose Munoz
- Barcelona Institute for Global Health, Barcelona, Spain
| | - Dominik Zenner
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK.,Centre for Infectious Disease Epidemiology, University College London, London, UK
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10
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Atchison C, Zenner D, Barnett L, Pareek M. Treating latent TB in primary care: a survey of enablers and barriers among UK General Practitioners. BMC Infect Dis 2015; 15:331. [PMID: 26268227 PMCID: PMC4535609 DOI: 10.1186/s12879-015-1091-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 08/05/2015] [Indexed: 11/25/2022] Open
Abstract
Background Treating latent tuberculosis infection (LTBI) is an important public health intervention. In the UK, LTBI treatment is delivered in secondary care. Treating LTBI in the community would move care closer to home and could increase uptake and treatment completion rates. However, healthcare providers’ views about the feasibility of this in the UK are unknown. This is the first study to investigate perceived barriers and enablers to primary care-based LTBI treatment among UK general practitioners (GPs). Methods A national survey amongst 140 randomly sampled UK GPs practising in areas of high TB incidence was performed. GPs’ experience and perceived confidence, barriers and enablers of primary care-based LTBI treatment were explored and multivariable logistic regression was used to determine whether these were associated with a GP’s willingness to deliver LTBI treatment. Results One hundred and twelve (80 %) GPs responded. Ninety-three (83 %; 95 % CI 75 %–89 %) GPs said they would be willing to deliver LTBI treatment in primary care, if key perceived barriers were addressed during service development. The major perceived barriers to delivering primary care-based LTBI treatment were insufficient experience among GPs of screening and treating LTBI, lack of timely specialist support and lack of allied healthcare staff. In addition, GPs felt that appropriate resourcing was key to the successful and sustainable delivery of the service. GPs who reported previous experience of screening or treatment of patients with active or latent TB were almost ten times more likely to be willing to deliver LTBI treatment in primary care compared to GPs with no experience (OR: 9.98; 95 % CI 1.22–81.51). Conclusions UK GPs support primary care-based LTBI treatment, provided they are given appropriate training, specialist support, staffing and financing. Electronic supplementary material The online version of this article (doi:10.1186/s12879-015-1091-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christina Atchison
- Department of Primary Care and Public Health, Imperial College London, Room 332, Reynolds Building, Charing Cross Campus, London, W6 8RF, UK.
| | - Dominik Zenner
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, NW9 5EQ, UK. .,Centre for Infectious Disease Epidemiology, University College London, London, NW1 2DA, UK. .,National Institute for Health Research Health Protection Research Unit in Respiratory Infections, Imperial College London, London, W6 8RF, UK.
| | - Lily Barnett
- Department of Primary Care and Public Health, Imperial College London, Room 332, Reynolds Building, Charing Cross Campus, London, W6 8RF, UK.
| | - Manish Pareek
- Centre for Infectious Disease Surveillance and Control, Public Health England, London, NW9 5EQ, UK. .,Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, LE1 9HN, UK.
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Pareek M, Watson JP, Ormerod LP, Kon OM, Woltmann G, White PJ, Abubakar I, Lalvani A. Screening of immigrants in the UK for imported latent tuberculosis: a multicentre cohort study and cost-effectiveness analysis. THE LANCET. INFECTIOUS DISEASES 2011; 11:435-44. [PMID: 21514236 PMCID: PMC3108102 DOI: 10.1016/s1473-3099(11)70069-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background Continuing rises in tuberculosis notifications in the UK are attributable to cases in foreign-born immigrants. National guidance for immigrant screening is hampered by a lack of data about the prevalence of, and risk factors for, latent tuberculosis infection in immigrants. We aimed to determine the prevalence of latent infection in immigrants to the UK to define which groups should be screened and to quantify cost-effectiveness. Methods In our multicentre cohort study and cost-effectiveness analysis we analysed demographic and test results from three centres in the UK (from 2008 to 2010) that used interferon-γ release-assay (IGRA) to screen immigrants aged 35 years or younger for latent tuberculosis infection. We assessed factors associated with latent infection by use of logistic regression and calculated the yields and cost-effectiveness of screening at different levels of tuberculosis incidence in immigrants' countries of origin with a decision analysis model. Findings Results for IGRA-based screening were positive in 245 of 1229 immigrants (20%), negative in 982 (80%), and indeterminate in two (0·2%). Positive results were independently associated with increases in tuberculosis incidence in immigrants' countries of origin (p=0·0006), male sex (p=0·046), and age (p<0·0001). National policy thus far would fail to detect 71% of individuals with latent infection. The two most cost-effective strategies were to screen individuals from countries with a tuberculosis incidence of more than 250 cases per 100 000 (incremental cost-effectiveness ratio [ICER] was £17 956 [£1=US$1·60] per prevented case of tuberculosis) and at more than 150 cases per 100 000 (including immigrants from the Indian subcontinent), which identified 92% of infected immigrants and prevented an additional 29 cases at an ICER of £20 819 per additional case averted. Interpretation Screening for latent infection can be implemented cost-effectively at a level of incidence that identifies most immigrants with latent tuberculosis, thereby preventing substantial numbers of future cases of active tuberculosis. Funding Medical Research Council and Wellcome Trust.
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Affiliation(s)
- Manish Pareek
- Department of Infectious Disease Epidemiology, Imperial College London, London, UK
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