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Said H, Kachingwe E, Gardee Y, Bhyat Z, Ratabane J, Erasmus L, Lebaka T, van der Meulen M, Gwala T, Omar S, Ismail F, Ismail N. Determining the risk-factors for molecular clustering of drug-resistant tuberculosis in South Africa. BMC Public Health 2023; 23:2329. [PMID: 38001453 PMCID: PMC10668341 DOI: 10.1186/s12889-023-17234-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 11/15/2023] [Indexed: 11/26/2023] Open
Abstract
BACKGROUND Drug-resistant tuberculosis (DR-TB) epidemic is driven mainly by the effect of ongoing transmission. In high-burden settings such as South Africa (SA), considerable demographic and geographic heterogeneity in DR-TB transmission exists. Thus, a better understanding of risk-factors for clustering can help to prioritise resources to specifically targeted high-risk groups as well as areas that contribute disproportionately to transmission. METHODS The study analyzed potential risk-factors for recent transmission in SA, using data collected from a sentinel molecular surveillance of DR-TB, by comparing demographic, clinical and epidemiologic characteristics with clustering and cluster sizes. A genotypic cluster was defined as two or more patients having identical patterns by the two genotyping methods used. Clustering was used as a proxy for recent transmission. Descriptive statistics and multinomial logistic regression were used. RESULT The study identified 277 clusters, with cluster size ranging between 2 and 259 cases. The majority (81.6%) of the clusters were small (2-5 cases) with few large (11-25 cases) and very large (≥ 26 cases) clusters identified mainly in Western Cape (WC), Eastern Cape (EC) and Mpumalanga (MP). In a multivariable model, patients in clusters including 11-25 and ≥ 26 individuals were more likely to be infected by Beijing family, have XDR-TB, living in Nelson Mandela Metro in EC or Umgungunglovo in Kwa-Zulu Natal (KZN) provinces, and having history of imprisonment. Individuals belonging in a small genotypic cluster were more likely to infected with Rifampicin resistant TB (RR-TB) and more likely to reside in Frances Baard in Northern Cape (NC). CONCLUSION Sociodemographic, clinical and bacterial risk-factors influenced rate of Mycobacterium tuberculosis (M. tuberculosis) genotypic clustering. Hence, high-risk groups and hotspot areas for clustering in EC, WC, KZN and MP should be prioritized for targeted intervention to prevent ongoing DR-TB transmission.
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Affiliation(s)
- Halima Said
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa.
| | - Elizabeth Kachingwe
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Yasmin Gardee
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Zaheda Bhyat
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - John Ratabane
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Linda Erasmus
- Centre for Enteric Diseases, National Institute of Communicable Diseases, Sandringham, Johannesburg, South Africa
| | - Tiisetso Lebaka
- Division of Surveillance and Outbreak Response, National Institute of Communicable Diseases, Sandringham, Johannesburg, South Africa
| | - Minty van der Meulen
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Thabisile Gwala
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Shaheed Omar
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Farzana Ismail
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
| | - Nazir Ismail
- Centre for Tuberculosis, National Institute of Communicable Diseases, Moderfontein Road, Sandringham, Johannesburg, code 2131, South Africa
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2
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Country-wide genotyping of Mycobacterium tuberculosis complex in Singapore, 2011–2017. Tuberculosis (Edinb) 2022; 134:102204. [DOI: 10.1016/j.tube.2022.102204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 03/23/2022] [Accepted: 03/29/2022] [Indexed: 11/18/2022]
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Suppli CH, Norman A, Folkvardsen DB, Gissel TN, Weinreich UM, Koch A, Wejse C, Lillebaek T. First outbreak of multi-drug resistant tuberculosis (MDR-TB) in Denmark involving six Danish-born cases. Int J Infect Dis 2022; 117:258-263. [PMID: 35158061 DOI: 10.1016/j.ijid.2022.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/05/2022] [Accepted: 02/08/2022] [Indexed: 10/19/2022] Open
Abstract
BACKGROUND Denmark is a tuberculosis (TB) and multi-drug resistant (MDR) TB low-incidence country at 5 and 0.05 cases per 100.000 population, respectively. Until 2018, transmission of MDR-TB was nonexistent except for few pairwise related family-cases. In this study we describe the first MDR-TB outbreak in Denmark. METHODS Based on genotyping of all Mycobacterium tuberculosis (Mtb) culture-positive cases in Denmark spanning three decades, six molecular- and epidemiologically linked Danish-born cases were identified as the first cluster of MDR-TB in Denmark. The primary case was diagnosed posthumously in 2010 followed by five epidemiologically linked cases from 2018 through 2019. RESULTS AND CONCLUSION Through a combination of routine Mtb genotyping and clinical epidemiological surveillance data, we identified the first Danish MDR-TB outbreak spanning 10 years and were able to disclose the specific transmission pathways in detail guiding the outbreak investigations. The occurrence of an MDR-TB outbreak in a resource rich TB low incidence setting like Denmark, highlights the importance of a collaborative control system combining classical contact tracing; timely identification of drug resistant TB through rapid diagnostics; and a close collaboration between clinicians, classical- and molecular epidemiologists for the benefit of TB control.
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Affiliation(s)
- Camilla Hiul Suppli
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut Artillerivej 5, DK-2300 Copenhagen, Denmark
| | - Anders Norman
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut Artillerivej 5, DK-2300 Copenhagen, Denmark
| | - Dorte Bek Folkvardsen
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut Artillerivej 5, DK-2300 Copenhagen, Denmark
| | - Tina Nørregaard Gissel
- Department of Internal Medicine, Region Hospital Viborg, Heibergs Alle 4F, DK-8800 Viborg, Denmark
| | - Ulla Møller Weinreich
- Department of Respiratory Diseases, Aalborg University Hospital, Aalborg, Mølleparkvej 4, DK-9000 Aalborg, Denmark; Department of Clinical Medicine, Aalborg University, Aalborg, Søndre Skovvej 15, DK-9000 Aalborg, Denmark
| | - Anders Koch
- Global Health Section, Department of Public Health, University of Copenhagen Øster Farimagsgade 5, DK-1353 Copenhagen, Denmark; Department of Infectious Disease Epidemiology and Prevention, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen, Denmark; Department of Infectious Diseases, Rigshospitalet University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
| | - Christian Wejse
- GloHAU, Center for Global Health, Dept of Public Health, Aarhus University, Bartholins Allé 2, DK-8000 Aarhus C, Denmark; Dept of Infectious Diseases, Institute for Clinical Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200 Aarhus N, Denmark
| | - Troels Lillebaek
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut Artillerivej 5, DK-2300 Copenhagen, Denmark; Global Health Section, Department of Public Health, University of Copenhagen Øster Farimagsgade 5, DK-1353 Copenhagen, Denmark.
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4
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Asgharzadeh M, Rashedi J, Poor BM, Kafil HS, Zadeh HM, Ahmadpour E. How Molecular Epidemiology Can Affect Tuberculosis Control in the Middle East Countries: A Systematic Review and Meta-Analysis. Infect Disord Drug Targets 2021; 21:28-37. [PMID: 31903887 DOI: 10.2174/1871526520666200106123619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/13/2019] [Accepted: 12/24/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Nowadays, due to the incidence of specific strains of Mycobacterium tuberculosis and also an increase in the rate of drug resistant-TB, the mortality rate has been increased by this disease. The identification of common strains in the region, as well as the sources of transmission, is essential to control the disease, which is possible by using molecular epidemiology. OBJECTIVES In this survey, the studies utilizing the spoligotyping method in Muslim Middle East countries are reviewed to determine their role in the control of TB. METHODS All studies conducted from 2005 to June 2016 were considered systematically in three electronic databases out of which 23 studies were finally selected. RESULTS The average rate of clustering was 84% and the rate of recent transmission varied from 21.7% to 92.4%. The incidence of Beijing strains has been found to be rising in the abovementioned countries. In Iran and Saudi Arabia known as immigration and labour-hosting countries, respectively, rapid transmittable and drug-resistant Beijing strains were higher than those in other Muslim Middle East countries. CONCLUSION Considering the incidence of highly virulent strains, due to the increase in immigration and people infected with HIV, tuberculosis, especially drug-resistant form, careful monitoring is needed.
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Affiliation(s)
- Mohammad Asgharzadeh
- Biotechnology Research Center, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Jalil Rashedi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behroz Mahdavi Poor
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Moharram Zadeh
- Women's Reproduction Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ehsan Ahmadpour
- Department of Medical Parasitology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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5
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Medina-Macías O, Stoesslé P, Perales-Rendón LE, Moreno-Cuevas JE, González-Salazar F. Latent tuberculosis in migrants travelling through the northeast regions of Mexico. J Clin Tuberc Other Mycobact Dis 2020; 21:100194. [PMID: 33195823 PMCID: PMC7644743 DOI: 10.1016/j.jctube.2020.100194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background Latent tuberculosis infection (LTBI) affects nearly a quarter of the global population. Public health interventions aimed at interrupting tuberculosis transmission do not routinely include systematic screening of migrant populations for LTBI in Mexico, nor other high-income countries. However, early detection and treatment of LTBI in immigrant populations from high-burden countries are recommended by the World Health Organization. Objective The objective of this study was to determine the proportion of migrants with LTBI in shelters in northeastern Mexico. Methods In this cross-sectional study, blood samples were obtained from 455 migrants living in shelters in northeastern Mexico during January 2017 to October 2019. LTBI was diagnosed using the QuantiFERON®-TB Gold Plus test. Results Most of the migrants evaluated in this study were from Honduras; ∼86% were male; the average age was 29 ± 10 years. LTBI was identified in 18.4% of those from Central America. Migrants from El Salvador and Nicaragua were more likely to have LTBI than those from Honduras or Guatemala. Overweight or obese persons and older persons had a higher prevalence of LTBI. We detected no significant differences with respect to LTBI when the results were compared based on gender, education, or marital status. Conclusion The LTBI rates amongst migrants from Central America recently screened in shelters in northeastern Mexico appears to be relatively low given recent estimates of LTBI prevalence in Mexico.
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Affiliation(s)
- Obed Medina-Macías
- División de Ciencias de La Salud, Departamento de Ciencias Básicas, Universidad de Monterrey, Monterrey, Mexico
| | - Philippe Stoesslé
- Departamento de Ciencias Sociales, Universidad de Monterrey, Monterrey, Mexico
| | - Leonardo E Perales-Rendón
- Centro de Investigaciones Biomédicas Del Noreste, Instituto Mexicano Del Seguro Social, Monterrey, Mexico
| | - Jorge E Moreno-Cuevas
- División de Ciencias de La Salud, Departamento de Ciencias Básicas, Universidad de Monterrey, Monterrey, Mexico
| | - Francisco González-Salazar
- División de Ciencias de La Salud, Departamento de Ciencias Básicas, Universidad de Monterrey, Monterrey, Mexico.,Centro de Investigaciones Biomédicas Del Noreste, Instituto Mexicano Del Seguro Social, Monterrey, Mexico
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6
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Tadokera R, Bekker LG, Kreiswirth BN, Mathema B, Middelkoop K. TB transmission is associated with prolonged stay in a low socio-economic, high burdened TB and HIV community in Cape Town, South Africa. BMC Infect Dis 2020; 20:120. [PMID: 32041530 PMCID: PMC7011372 DOI: 10.1186/s12879-020-4828-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 01/28/2020] [Indexed: 11/16/2022] Open
Abstract
Background While several studies have assessed the associations between biological factors and tuberculosis (TB) transmission, our understanding of the associations between TB transmission and social and economic factors remains incomplete. We aimed to explore associations between community TB transmission and socio-economic factors within a high TB-HIV burdened setting. Methods We conducted a cross-sectional molecular epidemiology study among adult patients attending a routine TB clinic. Demographic and clinical data were extracted from TB registers and clinical folders; social and economic data were collected using interviewer-administered questionnaires; Mycobacterium tuberculosis isolates were genotyped and classified as clustered/non-clustered using IS6110-based Restriction Fragment Length Polymorphism. Composite “social” and “economic” scores were generated from social and economic data. Data were analyzed using StataCorp version 15.0 software. Stratified, bivariable analyses were performed using chi-squared. Wilcoxon signed rank tests; univariable and multivariable logistic regression models were developed to explore associations in the social, economic, traditional and composite TB risk factors with TB transmission. Results Of the 505 patient Mtb strains, 348(69%) cases were classified as clustered and 157(31%) were non-clustered. Clustered cases were more likely to have lived longer in the study community, (odds ratio [OR] = 1.05, 95% Confidence interval [C.I]:1.02–1.09, p = 0.006); in the same house (OR = 1.04, C.I: 0.99–1.08, p = 0.06); and had increased household crowding conditions (i.e fewer rooms used for sleeping, OR = 0.45, C.I:0.21–0.95, p = 0.04). Although a higher proportion of clustered cases had a low economic score, no statistically significant association was found between clustering and either the economic score (p = 0.13) or social score (p = 0.26). Conclusions We report a novel association between Mtb transmission and prolonged stay within a high burdened community. Transmission was also associated with fewer rooms for sleeping in a household. Increased social interaction and prolonged residence in a high burdened community are important factors linked to Mtb transmission, possibly due to increased probability of higher effective contact rates. The possible importance of degrees of poverty within low socio-economic setting warrants further study.
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Affiliation(s)
- Rebecca Tadokera
- Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, PO Box 13801, Mowbray Observatory, Cape Town, 7705, South Africa.,NRF/DST Centre of Excellence for Biomedical Tuberculosis Research, Medical Research Council Centre for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
| | - Linda-Gail Bekker
- Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, PO Box 13801, Mowbray Observatory, Cape Town, 7705, South Africa.,Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Barry N Kreiswirth
- Public Health Research Institute Tuberculosis Center, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| | - Barun Mathema
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City, NY, USA
| | - Keren Middelkoop
- Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, PO Box 13801, Mowbray Observatory, Cape Town, 7705, South Africa. .,Department of Medicine, University of Cape Town, Cape Town, South Africa.
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7
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Black AT, Hamblion EL, Buttivant H, Anderson SR, Stone M, Casali N, Drobniewski F, Nwoguh F, Marshall BG, Booth L. Tracking and responding to an outbreak of tuberculosis using MIRU-VNTR genotyping and whole genome sequencing as epidemiological tools. J Public Health (Oxf) 2019; 40:e66-e73. [PMID: 29106587 DOI: 10.1093/pubmed/fdx075] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 06/13/2017] [Indexed: 11/13/2022] Open
Abstract
Background We describe an outbreak that contributed to a near doubling of the incidence of tuberculosis in Southampton, UK. We examine the importance of 24 locus mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) genotyping in its identification and management and the role of whole genome sequencing (WGS) in tracing the spread of the strain. Methods Outbreak cases were defined as those diagnosed between January and December 2011 with indistinguishable 24 locus-MIRU-VNTR genotypes or, cases linked epidemiologically. A cluster questionnaire was administered by TB nurses to identify contacts and social settings. Results Overall, 25 patients fulfilled the case definition. No cases with this MIRU-VNTR genotype had been detected in the UK previously. Connections were found between all cases through household contacts or social venues including a football club, Internet cafe and barber's shop. Public health actions included extended contact tracing, venue screening and TB awareness-raising. The outbreak resulted in a high rate of transmission and high incidence of clinical disease among contacts. Conclusions This outbreak illustrates the value of combining active case-finding with prospective MIRU-VNTR genotyping to identify settings to undertake public health action. In addition WGS revealed that the VNTR-defined cluster was a single outbreak and that active TB transmission not reactivation was responsible for this outbreak in non-UK born individuals.
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Affiliation(s)
- Anne T Black
- Public Health England Wessex Centre, Whiteley, Hampshire, UK
| | - Esther L Hamblion
- Public Health England, Field Epidemiology Service (Victoria), London, UK
| | - Helen Buttivant
- Health Education Wessex, Wessex School of Public Health, Winchester, Hampshire, UK
| | - Sarah R Anderson
- Public Health England, Field Epidemiology Service (Victoria), London, UK
| | | | - Nicola Casali
- National Mycobacterium Reference Laboratory, London, UK
| | | | | | - Ben G Marshall
- University Hospital of Southampton, Faculty of Southampton, Life Sciences Building, Highfield Campus, University of Southampton, Southampton, UK
| | - Linda Booth
- Public Health England Wessex Centre, Whiteley, Hampshire, UK
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8
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Barac A, Karimzadeh-Esfahani H, Pourostadi M, Rahimi MT, Ahmadpour E, Rashedi J, Mahdavipoor B, Kafil HS, Spotin A, Abate KH, Mathioudakis AG, Asgharzadeh M. Laboratory Cross-Contamination of Mycobacterium tuberculosis: A Systematic Review and Meta-analysis. Lung 2019; 197:651-661. [PMID: 31203380 DOI: 10.1007/s00408-019-00241-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 05/24/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Microbiological cultures are the mainstay of the diagnosis of tuberculosis (TB). False-positive TB results lead to significant unnecessary therapeutic and economic burden and are frequently caused by laboratory cross-contamination. The aim of this meta-analysis was to quantify the prevalence of laboratory cross-contamination. METHODS Through a systematic review of five electronic databases, we identified studies reporting rates of laboratory cross-contamination, confirmed by molecular techniques in TB cultures. We evaluated the quality of the identified studies using the National Institute of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies, and conducted a meta-analysis using standard methodology recommended by the Cochrane Collaboration. RESULTS Based on 31 eligible studies evaluating 29,839 TB cultures, we found that 2% (95% confidence intervals [CI] 1-2%) of all positive TB cultures represent false-positive results secondary to laboratory cross-contamination. More importantly, we evaluated the rate of laboratory cross-contamination in cases where a single-positive TB culture was available in addition to at least one negative TB culture, and we found a rate of 15% (95% CI 6-33%). Moreover, 9.2% (91/990) of all patients with a preliminary diagnosis of TB had false-positive results and received unnecessary and potentially harmful treatments. CONCLUSIONS Our results highlight a remarkably high prevalence of false-positive TB results as a result of laboratory cross-contamination, especially in single-positive TB cultures, leading to the administration of unnecessary, harmful treatments. The need for the adoption of strict technical standards for mycobacterial cultures cannot be overstated.
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Affiliation(s)
- Aleksandra Barac
- Clinic for Infectious and Tropical Diseases, Clinical Centre of Serbia, Belgrade, Serbia.,Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | | | - Mahya Pourostadi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Ehsan Ahmadpour
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. .,Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Jalil Rashedi
- Tuberculosis and Lung Disease Research Center, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behroz Mahdavipoor
- Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Medical Parasitology, School of Medical Sciences, Tarbiat Modarres University, Tehran, Iran
| | - Hossein Samadi Kafil
- Department of Microbiology, Tabriz University of Medical Sciences, Tabriz, Iran.,Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Adel Spotin
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Alexander G Mathioudakis
- Division of Infection, Immunity and Respiratory Medicine, The University of Manchester, Manchester, UK. .,North West Lung Centre, Wythenshawe Hospital, Manchester University NHS Foundation Trust, Manchester, UK.
| | - Mohammad Asgharzadeh
- Faculty of Paramedicine, Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Asare P, Asante-Poku A, Prah DA, Borrell S, Osei-Wusu S, Otchere ID, Forson A, Adjapong G, Koram KA, Gagneux S, Yeboah-Manu D. Reduced transmission of Mycobacterium africanum compared to Mycobacterium tuberculosis in urban West Africa. Int J Infect Dis 2018; 73:30-42. [PMID: 29879521 PMCID: PMC6069673 DOI: 10.1016/j.ijid.2018.05.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 05/23/2018] [Accepted: 05/29/2018] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Understanding transmission dynamics is useful for tuberculosis (TB) control. A population-based molecular epidemiological study was conducted to determine TB transmission in Ghana. METHODS Mycobacterium tuberculosis complex (MTBC) isolates obtained from prospectively sampled pulmonary TB patients between July 2012 and December 2015 were characterized using spoligotyping and standard 15-locus mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) typing for transmission studies. RESULTS Out of 2309 MTBC isolates, 1082 (46.9%) unique cases were identified, with 1227 (53.1%) isolates belonging to one of 276 clusters. The recent TB transmission rate was estimated to be 41.2%. Whereas TB strains of lineage 4 belonging to M. tuberculosis showed a high recent transmission rate (44.9%), reduced recent transmission rates were found for lineages of Mycobacterium africanum (lineage 5, 31.8%; lineage 6, 24.7%). CONCLUSIONS The study findings indicate high recent TB transmission, suggesting the occurrence of unsuspected outbreaks in Ghana. The observed reduced transmission rate of M. africanum suggests other factor(s) (host/environmental) may be responsible for its continuous presence in West Africa.
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Affiliation(s)
- Prince Asare
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana; West African Centre for Cell Biology of Infectious Pathogens, University of Ghana, Legon, Ghana; Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Ghana
| | - Adwoa Asante-Poku
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana
| | - Diana Ahu Prah
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana
| | - Sonia Borrell
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Stephen Osei-Wusu
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana
| | - Isaac Darko Otchere
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana
| | | | | | - Kwadwo Ansah Koram
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana
| | - Sebastien Gagneux
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Dorothy Yeboah-Manu
- Noguchi Memorial Institute for Medical Research (NMIMR), University of Ghana, Legon, Ghana.
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How effective are approaches to migrant screening for infectious diseases in Europe? A systematic review. THE LANCET. INFECTIOUS DISEASES 2018; 18:e259-e271. [PMID: 29778396 DOI: 10.1016/s1473-3099(18)30117-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/26/2018] [Accepted: 02/06/2018] [Indexed: 12/20/2022]
Abstract
Rates of migration to Europe, and within Europe, have increased in recent years, with considerable implications for health systems. Migrants in Europe face a disproportionate burden of tuberculosis, HIV, and hepatitis B and C, yet experience a large number of barriers to accessing statutory health care on arrival. A better understanding of how to deliver effective and cost-effective screening, vaccination, and health services to this group is now crucial. We did a systematic review to document and assess the effectiveness and cost-effectiveness of approaches used for infectious diseases screening, and to explore facilitators and barriers experienced by migrants to accessing screening programmes. Following PRISMA guidelines, we searched Embase, PubMed, PsychINFO, the Cochrane Library, and Web of Science (1989 to July 1, 2015, updated on Jan 1, 2018), with no language restrictions, and systematically approached experts across the European Union (EU) for grey literature. Inclusion criteria were primary research studies assessing screening interventions for any infectious disease in the migrant (foreign-born) population residing in EU or European Economic Area (EEA) countries. Primary outcomes were the following effectiveness indicators: uptake of screening, coverage, infections detected, and treatment outcomes. Of 4112 unique records, 47 studies met our inclusion criteria, from ten European countries (Belgium, Denmark, France, Italy, the Netherlands, Norway, Spain, Sweden, Switzerland, and the UK) encompassing 248 402 migrants. We found that most European countries screening migrants focus on single diseases only-predominantly active or latent tuberculosis infection-and specifically target asylum seekers and refugees, with 22 studies reporting on other infections (including HIV and hepatitis B and C). An infection was detected in 3·74% (range 0·00-95·16) of migrants. Latent tuberculosis had the highest prevalence across all infections (median 15·02% [0·35-31·81]). Uptake of screening by migrants was high (median 79·50% [18·62-100·00]), particularly in primary health-care settings (uptake 96·77% [76·00-100·00]). However, in 24·62% (0·12-78·99) of migrants screening was not completed and a final diagnosis was not made. Pooled data highlight high treatment completion in migrants (83·79%, range 0·00-100·00), yet data were highly heterogeneous for this outcome, masking important disparities between studies and infections, with only 54·45% (35·71-72·27) of migrants with latent tuberculosis ultimately completing treatment after screening. Coverage of the migrant population in Europe is low (39·29% [14·53-92·50]). Data on cost-effectiveness were scarce, but suggest moderate to high cost-effectiveness of migrant screening programmes depending on migrant group and disease targeted. European countries have adopted a variety of approaches to screening migrants for infections; however, these are limited in scope to single diseases and a narrow subset of migrants, with low coverage. More emphasis must be placed on developing innovative and sustainable strategies to facilitate screening and treatment completion and improve health outcomes, encompassing multiple key infections with consideration given to a wider group of high-risk migrants. Policy makers and researchers involved with global migration need to ensure a longer-term view on improving health outcomes in migrant populations as they integrate into health systems in host countries.
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Hamblion EL, Le Menach A, Anderson LF, Lalor MK, Brown T, Abubakar I, Anderson C, Maguire H, Anderson SR. Recent TB transmission, clustering and predictors of large clusters in London, 2010-2012: results from first 3 years of universal MIRU-VNTR strain typing. Thorax 2017; 71:749-56. [PMID: 27417280 PMCID: PMC4975838 DOI: 10.1136/thoraxjnl-2014-206608] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 02/12/2016] [Indexed: 11/29/2022]
Abstract
Background The incidence of TB has doubled in the last 20 years in London. A better understanding of risk groups for recent transmission is required to effectively target interventions. We investigated the molecular epidemiological characteristics of TB cases to estimate the proportion of cases due to recent transmission, and identify predictors for belonging to a cluster. Methods The study population included all culture-positive TB cases in London residents, notified between January 2010 and December 2012, strain typed using 24-loci multiple interspersed repetitive units-variable number tandem repeats. Multivariable logistic regression analysis was performed to assess the risk factors for clustering using sociodemographic and clinical characteristics of cases and for cluster size based on the characteristics of the first two cases. Results There were 10 147 cases of which 5728 (57%) were culture confirmed and 4790 isolates (84%) were typed. 2194 (46%) were clustered in 570 clusters, and the estimated proportion attributable to recent transmission was 34%. Clustered cases were more likely to be UK born, have pulmonary TB, a previous diagnosis, a history of substance abuse or alcohol abuse and imprisonment, be of white, Indian, black-African or Caribbean ethnicity. The time between notification of the first two cases was more likely to be <90 days in large clusters. Conclusions Up to a third of TB cases in London may be due to recent transmission. Resources should be directed to the timely investigation of clusters involving cases with risk factors, particularly those with a short period between the first two cases, to interrupt onward transmission of TB.
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Affiliation(s)
- Esther L Hamblion
- Field Epidemiology Services (Victoria), Public Health England, London, UK
| | - Arnaud Le Menach
- Field Epidemiology Services (Victoria), Public Health England, London, UK European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Control and Prevention, Stockholm, Sweden
| | - Laura F Anderson
- Tuberculosis Section, Respiratory Disease Department, Public Health England, London, UK
| | - Maeve K Lalor
- Tuberculosis Section, Respiratory Disease Department, Public Health England, London, UK
| | - Tim Brown
- National Mycobacterium Reference Laboratory, Institute of Cell and Molecular Science (ICMS), London, UK
| | - Ibrahim Abubakar
- Tuberculosis Section, Respiratory Disease Department, Public Health England, London, UK Centre for Infectious Disease Epidemiology, University College London, Mortimer Market Centre, London, UK
| | - Charlotte Anderson
- Field Epidemiology Services (Victoria), Public Health England, London, UK
| | - Helen Maguire
- Field Epidemiology Services (Victoria), Public Health England, London, UK European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Control and Prevention, Stockholm, Sweden
| | - Sarah R Anderson
- Field Epidemiology Services (Victoria), Public Health England, London, UK
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12
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Pourostadi M, Rashedi J, Mahdavi Poor B, Samadi Kafil H, Kazemi A, Asgharzadeh M. Tuberculosis Control and Role of Molecular Epidemiology Studies in Iran: A Systematic Review. TANAFFOS 2017; 16:190-200. [PMID: 29849672 PMCID: PMC5960223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Today because of immigration, HIV pandemic and spread of drug resistant tuberculosis, mortality caused by tuberculosis (TB) has increased. To control the disease it is essential to identify the sources of the infection and patterns of transmission. This becomes possible through using molecular epidemiology methods. MATERIALS AND METHODS This research reviewed studies based on IS6110-restriction fragment length polymorphism (IS6110-RFLP) as a primary method to recognize the role of molecular epidemiology researches in managing TB in Iran. Within 1995-2015 all human population based studies which had use IS6110-RFLP as the primary method systematically reviewed. RESULTS At the end, 11 articles were selected. The mean clustering rate obtained was 28.1%. The rate of recent transmission was variable from 2% to 49% and the mean value was determined 17%. CONCLUSION The studies revealed that in Iran both reactivation and recent transmission were significant in developing new cases of TB. Yet, reactivation plays greater role. If the matter is supervised insufficiently and carelessly, because of increasing rate of drug resistant TB, immigration of HIV infected individuals, TB especially drug resistant TB will be problematic in the near future.
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Affiliation(s)
- Mahya Pourostadi
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Jalil Rashedi
- Tuberculosis and Lung Diseases Research Center, and Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran.,Correspondence to: Rashedi J, Address: Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Golgasht Ave, Azadi St, Tabriz, Iran., Email address:
| | - Behroz Mahdavi Poor
- Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abdolhassan Kazemi
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Asgharzadeh
- Biotechnology Research Center, and Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, Iran
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13
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Pourostadi M, Rashedi J, Mahdavi Poor B, Samadi Kafil H, Shirazi S, Asgharzadeh M. Molecular Diversity of Mycobacterium tuberculosis Strains in Northwestern Iran. Jundishapur J Microbiol 2016; 9:e35520. [PMID: 27800145 PMCID: PMC5086081 DOI: 10.5812/jjm.35520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 07/23/2016] [Accepted: 08/07/2016] [Indexed: 11/22/2022] Open
Abstract
Background Years after the development of antituberculosis (TB) drugs, many people continue to suffer from this disease. To control the spread of TB, strains of the Mycobacterium tuberculosis complex need to be determined, and sources of infection must be identified. Such steps should help to prevent transmission of the infection. Objectives The aim of this study was to perform molecular genotyping of isolates of the M. tuberculosis complex obtained from patients in northwestern Iran. Methods One hundred ninety-four culture-positive M. tuberculosis isolates obtained from patients in northwestern Iran were analyzed using the mycobacterial interspersed repetitive unit-exact tandem repeats (MIRU-ETR) method. Results The MIRU-ETR method distinguished 162 different patterns in the 194 isolates, comprising 23 clusters and 139 unique patterns. Its discriminatory power according to the Hunter-Gaston discriminatory index (HGDI) was 0.9978. The largest cluster contained six isolates. Conclusions This research indicated that various strains of M. tuberculosis were responsible for TB and that the majority of cases were due to reactivation.
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Affiliation(s)
- Mahya Pourostadi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Jalil Rashedi
- Tuberculosis and Lung Disease Research Center, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, IR Iran
- Corresponding author: Jalil Rashedi, Tuberculosis and Lung Disease Research Center, Faculty of Paramedicine, Tabriz University of Medical Sciences, Golgasht Ave., Azadi St., Tabriz, IR Iran. Tel: +98-4133392633, Fax: +98-4133371971, E-mail:
| | - Behroz Mahdavi Poor
- Department of Laboratory Science, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, IR Iran
- Department of Medical Parasitology, Faculty of Medicine, Tarbiat Modares University, Tehran, IR Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Samaneh Shirazi
- Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Mohammad Asgharzadeh
- Hematology-Oncology Research Center, Faculty of Paramedicine, Tabriz University of Medical Sciences, Tabriz, IR Iran
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14
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Satta G, Witney AA, Shorten RJ, Karlikowska M, Lipman M, McHugh TD. Genetic variation in Mycobacterium tuberculosis isolates from a London outbreak associated with isoniazid resistance. BMC Med 2016; 14:117. [PMID: 27530812 PMCID: PMC4988016 DOI: 10.1186/s12916-016-0659-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 07/26/2016] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The largest outbreak of isoniazid-resistant (INH-R) Mycobacterium tuberculosis in Western Europe is centred in North London, with over 400 cases diagnosed since 1995. In the current study, we evaluated the genetic variation in a subset of clinical samples from the outbreak with the hypothesis that these isolates have unique biological characteristics that have served to prolong the outbreak. METHODS Fitness assays, mutation rate estimation, and whole-genome sequencing were performed to test for selective advantage and compensatory mutations. RESULTS This detailed analysis of the genetic variation of these INH-R samples suggests that this outbreak consists of successful, closely related, circulating strains with heterogeneous resistance profiles and little or no associated fitness cost or impact on their mutation rate. CONCLUSIONS Specific deletions and SNPs could be a peculiar feature of these INH-R M. tuberculosis isolates, and could potentially explain their persistence over the years.
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Affiliation(s)
- Giovanni Satta
- Department of Infection, Centre for Clinical Microbiology, University College London, London, UK. .,Imperial College Healthcare NHS Trust, London, UK.
| | - Adam A Witney
- Institute of Infection and Immunity, St George's, University of London, London, UK
| | - Robert J Shorten
- Department of Infection, Centre for Clinical Microbiology, University College London, London, UK.,Public Health Laboratory Manchester, Manchester Royal Infirmary, Manchester, UK
| | - Magdalena Karlikowska
- Department of Infection, Centre for Clinical Microbiology, University College London, London, UK
| | - Marc Lipman
- Royal Free London NHS Foundation Trust, London, UK.,UCL Respiratory, Division of Medicine, University College London, London, UK
| | - Timothy D McHugh
- Department of Infection, Centre for Clinical Microbiology, University College London, London, UK
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15
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Iliaz S, Caglar E, Koksalan OK, Chousein EGU. An outbreak of multidrug-resistant tuberculosis among a family. Indian J Tuberc 2016; 63:130-2. [PMID: 27451825 DOI: 10.1016/j.ijtb.2015.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/01/2015] [Accepted: 07/13/2015] [Indexed: 11/25/2022]
Abstract
Tuberculosis is a major public health problem and it may be complicated by multidrug-resistant tuberculosis (MDR-TB). Wide transmission among immunocompetent contacts of the index case is possible. If you detect tuberculosis in two contacts of the index case, it is called an outbreak. The aim of our paper is to evaluate the characteristics of a MDR-TB outbreak affecting 7 people in a family treated during 2012-2014 in Istanbul Yedikule Training and Research Hospital for Chest Disease and Thoracic Surgery, Turkey. The cultures, spoligotyping, and DNA fingerprinting revealed the same Mycobacterium tuberculosis species as T1 genotype and ST53 subtype. All patients were negative for human immunodeficiency virus and free of other underlying diseases.
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Affiliation(s)
- Sinem Iliaz
- Yedikule Training and Research Hospital for Chest Disease and Thoracic Surgery, Department of Pulmonary Medicine, Zeytinburnu, Istanbul, Turkey.
| | - Emel Caglar
- Yedikule Training and Research Hospital for Chest Disease and Thoracic Surgery, Department of Pulmonary Medicine, Zeytinburnu, Istanbul, Turkey
| | - Orhan Kaya Koksalan
- Istanbul University, Institute for Medical Experimental Research, Molecular Tuberculosis Epidemiology Laboratory, Fatih, Istanbul, Turkey
| | - Efsun Gonca Ugur Chousein
- Yedikule Training and Research Hospital for Chest Disease and Thoracic Surgery, Department of Pulmonary Medicine, Zeytinburnu, Istanbul, Turkey
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16
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17
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Severi E, Maguire H, Ihekweazu C, Bickler G, Abubakar I. Outcomes analysis of new entrant screening for active tuberculosis in Heathrow and Gatwick airports, United Kingdom 2009/2010. BMC Infect Dis 2016; 16:178. [PMID: 27102741 PMCID: PMC4840491 DOI: 10.1186/s12879-016-1506-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 04/09/2016] [Indexed: 12/18/2022] Open
Abstract
Background In 2012, the United Kingdom (UK) Government announced that the new entrant screening for active tuberculosis (TB) in Heathrow and Gatwick airports would end. Our study objective was to estimate screening yield and diagnostic accuracy, and identify those at risk of active TB after entry. Methods We designed a retrospective cohort study and linked new entrants screened from June 2009 to September 2010 through probabilistic matching with UK Enhanced TB Surveillance (ETS) data (June 2009 to December 2010). Yield was the proportion of cases reported to ETS within three months of airport screening in the screened population. To estimate screening diagnostic accuracy we assessed sensitivity, specificity, positive and negative predictive values. Through Poisson regression we identified groups at increased risk of TB diagnosis after entry. Results We identified 200,199 screened entrants, of these 59 had suspected TB at screening and were reported within 3 months to ETS (yield = 0.03 %). Sensitivity was 26 %; specificity was 99.7 %; positive predictive value was 13.2 %; negative predictive value was 99.9 %. Overall, 350 entrants were reported in ETS. Persons from countries with annual TB incidence higher than 150 cases per 100,000 population and refugees and asylum seekers were at increased risk of TB diagnosis after entry (population attributable risk 77 and 3 % respectively). Conclusion Airport screening has very low screening yields, sensitivity and positive predictive value. New entrants coming from countries with annual TB incidence higher than 150 per 100,000 population, refugees and asylum seekers should be prioritised at pre- or post-entry screening.
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Affiliation(s)
- Ettore Severi
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, Stockholm, 17183, Sweden.,Health Protection Agency (HPA), London, SW1W 9SZ, UK.,Present address: European Centre for Disease Prevention and Control, Surveillance and Response Support Unit, Stockholm, 17183, Sweden
| | - Helen Maguire
- European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, Stockholm, 17183, Sweden.,Health Protection Agency (HPA), London, SW1W 9SZ, UK
| | | | | | - Ibrahim Abubakar
- University College London, Centre for Infectious Disease Epidemiology, London, WC1E 6BT, UK. .,Health Protection Agency, Colindale, NW9 5EQ, UK.
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18
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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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19
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Saavedra-Campos M, Welfare W, Cleary P, Sails A, Burkitt A, Hungerford D, Okereke E, Acheson P, Petrovic M. Identifying areas and risk groups with localisedMycobacterium tuberculosistransmission in northern England from 2010 to 2012: spatiotemporal analysis incorporating highly discriminatory genotyping data. Thorax 2015; 71:742-8. [DOI: 10.1136/thoraxjnl-2014-206416] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 03/30/2015] [Indexed: 02/04/2023]
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20
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Griffiths C, Barne M, Saxena P, Yaphe J. Challenges of tuberculosis management in high and low prevalence countries in a mobile world. PRIMARY CARE RESPIRATORY JOURNAL : JOURNAL OF THE GENERAL PRACTICE AIRWAYS GROUP 2014; 23:106-11. [PMID: 24615415 PMCID: PMC6442296 DOI: 10.4104/pcrj.2014.00019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chris Griffiths
- Professor of Primary Care, Centre for Primary Care and Public Health, Blizard Institute, Queen Mary University of London, London, UK
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21
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Abarca Tomás B, Pell C, Bueno Cavanillas A, Guillén Solvas J, Pool R, Roura M. Tuberculosis in migrant populations. A systematic review of the qualitative literature. PLoS One 2013; 8:e82440. [PMID: 24349284 PMCID: PMC3857814 DOI: 10.1371/journal.pone.0082440] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Accepted: 10/24/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The re-emergence of tuberculosis (TB) in low-incidence countries and its disproportionate burden on immigrants is a public health concern posing specific social and ethical challenges. This review explores perceptions, knowledge, attitudes and treatment adherence behaviour relating to TB and their social implications as reported in the qualitative literature. METHODS Systematic review in four electronic databases. Findings from thirty selected studies extracted, tabulated, compared and synthesized. FINDINGS TB was attributed to many non-exclusive causes including air-born transmission of bacteria, genetics, malnutrition, excessive work, irresponsible lifestyles, casual contact with infected persons or objects; and exposure to low temperatures, dirt, stress and witchcraft. Perceived as curable but potentially lethal and highly contagious, there was confusion around a condition surrounded by fears. A range of economic, legislative, cultural, social and health system barriers could delay treatment seeking. Fears of deportation and having contacts traced could prevent individuals from seeking medical assistance. Once on treatment, family support and "the personal touch" of health providers emerged as key factors facilitating adherence. The concept of latent infection was difficult to comprehend and while TB screening was often seen as a socially responsible act, it could be perceived as discriminatory. Immigration and the infectiousness of TB mutually reinforced each another exacerbating stigma. This was further aggravated by indirect costs such as losing a job, being evicted by a landlord or not being able to attend school. CONCLUSIONS Understanding immigrants' views of TB and the obstacles that they face when accessing the health system and adhering to a treatment programme-taking into consideration their previous experiences at countries of origin as well as the social, economic and legislative context in which they live at host countries- has an important role and should be considered in the design, evaluation and adaptation of programmes.
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Affiliation(s)
- Bruno Abarca Tomás
- Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain
| | - Christopher Pell
- Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- Centre for Social Science and Global Health, University of Amsterdam, Amsterdam, The Netherlands
| | - Aurora Bueno Cavanillas
- Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain
- Service of Preventive Medicine, San Cecilio University Hospital, Granada, Spain
- Consorcio de Investigación Biomédica en Red en Epidemiología y Salud Públic, (CIBERESP), Madrid, Spain
| | - José Guillén Solvas
- Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain
- Service of Preventive Medicine, San Cecilio University Hospital, Granada, Spain
- Consorcio de Investigación Biomédica en Red en Epidemiología y Salud Públic, (CIBERESP), Madrid, Spain
| | - Robert Pool
- Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- Centre for Social Science and Global Health, University of Amsterdam, Amsterdam, The Netherlands
| | - María Roura
- Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
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22
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Padovese V, Egidi AM, Melillo TF, Farrugia B, Carabot P, Didero D, Costanzo G, Mirisola C. Prevalence of latent tuberculosis, syphilis, hepatitis B and C among asylum seekers in Malta. J Public Health (Oxf) 2013; 36:22-7. [PMID: 23559596 DOI: 10.1093/pubmed/fdt036] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND In the last few years, Malta has witnessed increasing immigration flows from the Libyan coasts. Public health policies are focused on screening migrants for tuberculosis, whereas no systematic actions against STIs are implemented. The aim of this study is to define the epidemiological profile of asylum seekers in Malta as regards syphilis, hepatitis B, C and latent tuberculosis, thus supporting screening policies. METHODS Five hundred migrants living in open centres were screened between December 2010 and June 2011. RESULTS 83.2% of people was from Somalia, 81.2% males, average age 26.5 years. The tuberculin skin test (TST) was positive in 225 migrants (45%). Latent syphilis was diagnosed in 11 migrants, hepatitis C in 3 and 31 migrants were HBsAg positive. CONCLUSION Systematic screening for asymptomatic migrants in Malta is not recommended for hepatitis C and syphilis, given the low prevalence observed. On the contrary, it should be considered for hepatitis B. TST could be indicated as the first step of a two step screening for migrants from countries with high TB incidence. Efficacy and cost-effectiveness could be achieved by further targeting screening to specific subgroups at higher risk of reactivation, such as people living with HIV and subjects affected by chronic diseases.
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Affiliation(s)
- V Padovese
- National Institute for Health, Migration and Poverty (NIHMP), Via di San Gallicano 25/A, Rome 00153, Italy
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Wagner KS, Lawrence J, Anderson L, Yin Z, Delpech V, Chiodini PL, Redman C, Jones J. Migrant health and infectious diseases in the UK: findings from the last 10 years of surveillance. J Public Health (Oxf) 2013; 36:28-35. [PMID: 23520266 DOI: 10.1093/pubmed/fdt021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Migrants account for an increasing proportion of the UK population. They are at risk of acquiring infectious diseases in their country of origin (prior to migration or during return visits), during migration, as well as in their destination country. Migrants can therefore have different risk profiles to the indigenous population. METHODS UK enhanced surveillance data for TB, HIV, malaria and enteric fever were analysed, with a focus on 2010, for migrant (non-UK born) populations. RESULTS South Asia was the most common region of birth for TB and enteric fever cases (57 and 80% of migrant cases, respectively). Sub-Saharan Africa was the predominant region of birth for HIV in heterosexuals and malaria cases (80 and 75% of migrant cases, respectively). The majority of cases of TB, HIV in heterosexuals, malaria and enteric fever reported in the UK are migrants. Among UK-born cases, ethnic minorities are disproportionately represented. CONCLUSIONS This analysis highlights the importance of considering, and improving the recording of, country of birth as a risk factor for infection. Consideration of multiple health risks is of value for migrant patients, and this has implications for the design of improved preventative strategies.
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Affiliation(s)
- K S Wagner
- Travel and Migrant Health Section, Health Protection Agency, London NW9 5EQ, UK
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Bothamley GH, Kruijshaar ME, Kunst H, Woltmann G, Cotton M, Saralaya D, Woodhead MA, Watson JP, Chapman ALN. Tuberculosis in UK cities: workload and effectiveness of tuberculosis control programmes. BMC Public Health 2011; 11:896. [PMID: 22122757 PMCID: PMC3235177 DOI: 10.1186/1471-2458-11-896] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 11/28/2011] [Indexed: 11/10/2022] Open
Abstract
Background Tuberculosis (TB) has increased within the UK and, in response, targets for TB control have been set and interventions recommended. The question was whether these had been implemented and, if so, had they been effective in reducing TB cases. Methods Epidemiological data were obtained from enhanced surveillance and clinics. Primary care trusts or TB clinics with an average of > 100 TB cases per year were identified and provided reflections on the reasons for any change in their local incidence, which was compared to an audit against the national TB plan. Results Access to data for planning varied (0-22 months). Sputum smear status was usually well recorded within the clinics. All cities had TB networks, a key worker for each case, free treatment and arrangements to treat HIV co-infection. Achievement of targets in the national plan correlated well with change in workload figures for the commissioning organizations (Spearman's rank correlation R = 0.8, P < 0.01) but not with clinic numbers. Four cities had not achieved the target of one nurse per 40 notifications (Birmingham, Bradford, Manchester and Sheffield). Compared to other cities, their loss to follow-up during treatment was usually > 6% (χ2 = 4.2, P < 0.05), there was less TB detected by screening and less outreach. Manchester was most poorly resourced and showed the highest rate of increase of TB. Direct referral from radiology, sputum from primary care and outreach workers were cited as important in TB control. Conclusion TB control programmes depend on adequate numbers of specialist TB nurses for early detection and case-holding. Please see related article: http://www.biomedcentral.com/1741-7015/9/127
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Weisenberg SA, Gibson AL, Huard RC, Kurepina N, Bang H, Lazzarini LCO, Chiu Y, Li J, Ahuja S, Driscoll J, Kreiswirth BN, Ho JL. Distinct clinical and epidemiological features of tuberculosis in New York City caused by the RD(Rio) Mycobacterium tuberculosis sublineage. INFECTION GENETICS AND EVOLUTION 2011; 12:664-70. [PMID: 21835266 DOI: 10.1016/j.meegid.2011.07.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 07/22/2011] [Accepted: 07/26/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND Genetic tracking of Mycobacterium tuberculosis is a cornerstone of tuberculosis (TB) control programs. The RD(Rio) M. tuberculosis sublineage was previously associated with TB in Brazil. We investigated 3847 M. tuberculosis isolates and registry data from New York City (NYC) (2001-2005) to: (1) affirm the position of RD(Rio) strains within the M. tuberculosis phylogenetic structure, (2) determine its prevalence, and (3) define transmission, demographic, and clinical characteristics associated with RD(Rio) TB. METHODS Isolates classified as RD(Rio) or non-RD(Rio) M. tuberculosis by multiplex PCR were further classified as clustered (≥2 isolates) or unique based primarily upon IS6110-RFLP patterns and lineage-specific cluster proportions were calculated. The secondary case rate of RD(Rio) was compared with other prevalent M. tuberculosis lineages. Genotype data were merged with the data from the NYC TB Registry to assess demographic and clinical characteristics. RESULTS RD(Rio) strains were found to: (1) be restricted to the Latin American-Mediterranean family, (2) cause approximately 8% of TB cases in NYC, and (3) be associated with heightened transmission as shown by: (i) a higher cluster proportion compared to other prevalent lineages, (ii) a higher secondary case rate, and (iii) cases in children. Furthermore, RD(Rio) strains were significantly associated with US-born Black or Hispanic race, birth in Latin American and Caribbean countries, and isoniazid resistance. CONCLUSIONS The RD(Rio) genotype is a single M. tuberculosis strain population that is emerging in NYC. The findings suggest that expanded RD(Rio) case and exposure identification could be of benefit due to its association with heightened transmission.
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Affiliation(s)
- Scott A Weisenberg
- Division of Infectious Diseases, Department of Medicine, Weill Medical College of Cornell University, New York, NY, USA
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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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Lucerna MA, Rodríguez-Contreras R, Barroso P, Martínez MJ, Sánchez-Benítez ML, García de Viedma D. [Molecular epidemiology of tuberculosis in Almeria (Spain). Factors associated with recent transmission]. Enferm Infecc Microbiol Clin 2011; 29:174-8. [PMID: 21353342 DOI: 10.1016/j.eimc.2010.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 06/22/2010] [Accepted: 06/29/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND Molecular epidemiology is used in tuberculosis (TB) to identify clusters in which the cases are assumed to belong to the same recent transmission chain. An endogenous reactivation of latent TB is considered when the Mycobacterium tuberculosis isolates have a unique genotype. OBJECTIVE To describe factors associated with recent transmission of TB in Almeria, from 2003-2007. METHODS We conducted an observational prospective study that included patients with Mycobacterium tuberculosis positive culture. The strains were genotyped by Restriction Fragment Length Polymorphism and spoligotyping. Adjusted odds ratio and 95% confidence intervals were calculated to study factors associated with cluster groups, using a multivariate logistic regression model. RESULTS We analysed 427 isolates, of which 71% were from males and 56.2% of them belonged to foreign residents. Furthermore, 44% were classified as a cluster. The resistance to isoniazid was 8.4%. The factors associated with clusters were age, principally the group under 10 years (adjusted OR=12.75; 95% CI, 2.52-64.58) and the group aged between 50-59 years (adjusted OR=13.85; 95% CI, 3.04-63.17), and born in Spain (adjusted OR=2.17; 95% CI, 1.41-3.36). CONCLUSIONS In Almeria, native population, children under 10 years old and patients aged between 50-59 years have more probability to belong to the same recent transmission chain. The molecular epidemiology can be used to find out which population groups need more control and this information must be used in tuberculosis prevention programs.
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Genotypes and characteristics of clustering and drug susceptibility of Mycobacterium tuberculosis isolates collected in Heilongjiang Province, China. J Clin Microbiol 2011; 49:1354-62. [PMID: 21325562 DOI: 10.1128/jcm.02274-10] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
For the last decade China has occupied second place, after India, among the top five countries with high burdens of tuberculosis (TB). Heilongjiang Province is located in northeastern China. The prevalence of drug-resistant TB in Heilongjiang Province is higher than the average level in China. To determine the transmission characteristics of Mycobacterium tuberculosis strains isolated in this area and their genetic relationships, especially among the Beijing family strains, we investigated their genotypes. From May 2007 to October 2008, 200 M. tuberculosis isolates from patients presenting pulmonary TB were analyzed by molecular typing using PCR-based methods: spacer-oligonucleotide typing (spoligotyping), Beijing family-specific PCR (detection of the deletion of region of difference 105 [RD105]), and mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. Different combinations of MIRU-VNTR loci were evaluated to define the genotypes and clustering characteristics of the local strains. We found that Beijing family strains represented 89.5% of the isolates studied. However, the rates of multidrug-resistant (MDR) M. tuberculosis among Beijing and non-Beijing family strains were not statistically different. The 15-locus set is considered the optimal MIRU-VNTR locus combination for analyzing the M. tuberculosis strains epidemic in this area, while the 10-locus set is an ideal set for first-line molecular typing. We found that the clustering rate of all the M. tuberculosis isolates analyzed was 10.0% using the 15-locus set typing. We conclude that the Beijing family genotype is predominant and that highly epidemic TB and MDR TB are less likely associated with the active transmission of M. tuberculosis in the study area.
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Nava-Aguilera E, López-Vidal Y, Harris E, Morales-Pérez A, Mitchell S, Flores-Moreno M, Villegas-Arrizón A, Legorreta-Soberanis J, Ledogar R, Andersson N. Clustering of Mycobacterium tuberculosis cases in Acapulco: Spoligotyping and risk factors. Clin Dev Immunol 2010; 2011:408375. [PMID: 21197077 PMCID: PMC3004385 DOI: 10.1155/2011/408375] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 09/28/2010] [Accepted: 10/12/2010] [Indexed: 11/18/2022]
Abstract
Recurrence and reinfection of tuberculosis have quite different implications for prevention. We identified 267 spoligotypes of Mycobacterium tuberculosis from consecutive tuberculosis patients in Acapulco, Mexico, to assess the level of clustering and risk factors for clustered strains. Point cluster analysis examined spatial clustering. Risk analysis relied on the Mantel Haenszel procedure to examine bivariate associations, then to develop risk profiles of combinations of risk factors. Supplementary analysis of the spoligotyping data used SpolTools. Spoligotyping identified 85 types, 50 of them previously unreported. The five most common spoligotypes accounted for 55% of tuberculosis cases. One cluster of 70 patients (26% of the series) produced a single spoligotype from the Manila Family (Clade EAI2). The high proportion (78%) of patients infected with cluster strains is compatible with recent transmission of TB in Acapulco. Geomatic analysis showed no spatial clustering; clustering was associated with a risk profile of uneducated cases who lived in single-room dwellings. The Manila emerging strain accounted for one in every four cases, confirming that one strain can predominate in a hyperendemic area.
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Affiliation(s)
- Elizabeth Nava-Aguilera
- Centro de Investigación de Enfermedades Tropicales, Universidad Autónoma de Guerrero, Calle Pino S/N, Colonia El Roble, 39640 Acapulco, Guerrero, Mexico.
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Melzer M, Gupta N, Petersen I, Cook S, Hall B. Previous treatment in predicting drug-resistant tuberculosis in an area bordering East London, UK. Int J Infect Dis 2010; 14:e717-22. [DOI: 10.1016/j.ijid.2010.02.2247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 01/08/2010] [Accepted: 02/09/2010] [Indexed: 10/19/2022] Open
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Gallego B, Sintchenko V, Jelfs P, Coiera E, Gilbert GL. Three-year longitudinal study of genotypes of Mycobacterium tuberculosis in a low prevalence population. Pathology 2010; 42:267-72. [PMID: 20350221 DOI: 10.3109/00313021003631346] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To investigate the molecular epidemiology of tuberculosis, temporal and spatial distribution of Mycobacterium tuberculosis isolates and associations between genotypes and clinical characteristics, in a low prevalence population. METHODS A total of 930 M. tuberculosis isolates referred to the New South Wales (NSW, Australia) Mycobacterium Reference Laboratory in 2004-2006 were characterised by mycobacterial interspersed repetitive unit (MIRU) and spacer oligonucleotide (spoligo) typing. Associations between genotypes, patient age, disease site and drug resistance were explored and the predictive power of molecular typing was analysed using Bayesian Belief Networks. RESULTS Among isolates from 855 NSW residents, there were 287 spoligotypes, 494 MIRU types and 643 unique spoligotype-MIRU type combinations. They formed 73 spoligotype, 104 MIRU type and 76 spoligo-MIRU clusters, most of which contained only two isolates. The majority (87.7%) of spoligotype clusters contained several MIRU profiles and 64.4% of MIRU clusters contained several spoligotypes. The three most common M. tuberculosis clades were Beijing (24.1%), East African Indian (11.8%) and Central Asian (6.5%); 6.9% and 0.7% isolates were resistant to isoniazid and rifampicin, respectively. There was no proof of association between genotype and drug resistance but isoniazid resistance increased independently over time. Given the low rates of genotype clustering, statistical analysis of genotype-phenotype associations was limited. Potential associations were not confirmed by Bayesian classifiers. CONCLUSIONS Spoligo and MIRU typing demonstrated low levels of M. tuberculosis clustering in NSW; temporal and spatial changes in M. tuberculosis genotypes reflected migration patterns to Australia. No analytically significant associations between M. tuberculosis genotypes and clinical phenotypes were detected.
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Affiliation(s)
- Blanca Gallego
- Centre for Health Informatics, University of New South Wales, Sydney, Australia
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Al-Hajoj SA. Tuberculosis in Saudi Arabia: can we change the way we deal with the disease? J Infect Public Health 2010; 3:17-24. [PMID: 20701887 DOI: 10.1016/j.jiph.2009.12.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 09/28/2009] [Accepted: 12/13/2009] [Indexed: 11/17/2022] Open
Abstract
Infection from Mycobacterium tuberculosis results in the death of three million people worldwide per annum of which an estimated one thousand are in Saudi Arabia. The WHO has set a target for successful treatment of 85% but Saudi Arabia is currently not meeting that target. We believe that the first step in improving the control of tuberculosis in Saudi Arabia is to improve and unify the standards of diagnostic services and laboratories responsible for tuberculosis. This paper reviews the current status and suggests possible improvements.
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Affiliation(s)
- Sahal Abdulaziz Al-Hajoj
- Department of Comparative Medicine, King Faisal Specialist Hospital & Research Centre (MBC 03), PO Box 3354, Riyadh 11211, Saudi Arabia.
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Velji P, Nikolayevskyy V, Brown T, Drobniewski F. Discriminatory ability of hypervariable variable number tandem repeat loci in population-based analysis of Mycobacterium tuberculosis strains, London, UK. Emerg Infect Dis 2010; 15:1609-16. [PMID: 19861054 PMCID: PMC2866407 DOI: 10.3201/eid1510.090463] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
To address conflicting results about the stability of variable number tandem repeat (VNTR) loci and their value in prospective molecular epidemiology of Mycobacterium tuberculosis, we conducted a large prospective population-based analysis of all M. tuberculosis strains in a metropolitan setting. Optimal and reproducible conditions for reliable PCR and fragment analysis, comprising enzymes, denaturing conditions, and capillary temperature, were identified for a panel of hypervariable loci, including 3232, 2163a, 1982, and 4052. A total of 2,261 individual M. tuberculosis isolates and 265 sets of serial isolates were analyzed by using a standardized 15-loci VNTR panel, then an optimized hypervariable loci panel. The discriminative ability of loci varied substantially; locus VNTR 3232 varied the most, with 19 allelic variants and Hunter-Gaston index value of 0.909. Hypervariable loci should be included in standardized panels because they can provide consistent comparable results at multiple settings, provided the proposed conditions are adhered to.
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Affiliation(s)
- Preya Velji
- Barts and The London School of Medicine, Queen Mary, University of London, London, UK
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Barniol J, Niemann S, Louis VR, Brodhun B, Dreweck C, Richter E, Becher H, Haas W, Junghanss T. Transmission dynamics of pulmonary tuberculosis between autochthonous and immigrant sub-populations. BMC Infect Dis 2009; 9:197. [PMID: 19961606 PMCID: PMC3224697 DOI: 10.1186/1471-2334-9-197] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 12/04/2009] [Indexed: 12/03/2022] Open
Abstract
Background The overall incidence of tuberculosis (TB) in Western Europe has been declining since the 19th Century. However, immigrant sub-groups from high-prevalence countries are slowing down this trend. The aim of this study was to describe how immigration influences TB transmission in Germany. For that we prospectively investigated the dynamics of TB transmission between TB high-prevalence immigrant and TB low-prevalence local populations with molecular epidemiological methods and conventional contact investigations. Besides, we assessed transmission in relation to social mixing using an innovative tool that measures the integration of immigrants into the local social environment. Methods A prospective study of confirmed culture positive cases of pulmonary TB and their contacts was carried out in a German federal state from 2003 to 2005. Data for the study included: 1) case data routinely collected by the local public health staff and transmitted to the state health office and the national surveillance centre, 2) a study questionnaire designed to capture social interactions of relevance for TB transmission and 3) molecular genotyping data (IS6110 DNA fingerprint and spoligotyping). The proportion of German cases caused by foreign-born cases, and vice versa, was estimated and an integration index was computed using a selected set of questions from the study questionnaire. Results A total of 749 cases of culture-positive pulmonary tuberculosis voluntarily enrolled in the study, representing 57.8% of all registered cases diagnosed over the study period. Data that included study questionnaire and DNA fingerprinting were available for 41% (n = 308) of the study participants. Forty-seven clusters, defined as a least two cases infected by the same TB strains, were identified by molecular methods and included 132 (17%) of the study participants. Epidemiological links were identified for 28% of the clusters by conventional epidemiological data. In mixed clusters, defined as clusters including German and foreign-born individuals, the probability of cases to be caused by foreign-born cases was estimated at 18.3%. We observed a trend to mixed clusters with increasing time spent by immigrants in the host country. This group also presented comparatively higher integration indexes than immigrants in immigrant-only clusters. Conclusion Our results confirm the findings of other studies that there is no significant TB transmission from TB high-prevalence immigrant to TB low-prevalence autochthonous population. This may be explained by the good performance of tuberculosis screening programmes for certain groups arriving in Germany from high- prevalence countries, by a low degree of mixing of immigrants with the local population or by a combination of both.
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Affiliation(s)
- Judit Barniol
- Section Clinical Tropical Medicine, Department for Infectious Diseases, University Hospital Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
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Abstract
OBJECTIVE To investigate the incidence of, and risk factors for, tuberculosis among HIV clinic attendees in the United Kingdom. DESIGN AND METHODS Observational cohort study of 27 868 individuals in the United Kingdom Collaborative HIV Cohort collaboration, 1996-2005. RESULTS Among individuals not taking combination antiretroviral therapy (cART), tuberculosis incidence was considerably higher among individuals of black African vs. white or other ethnicities {incidence rates 9.9 [95% confidence intervals (CIs) 7.2, 12.6], 2.5 [95% CI 1.8, 3.0] and 4.4 [95% CI 2.7, 6.0] episodes per 1000 person-years, respectively}. Tuberculosis incidence decreased with time after starting cART; among black Africans, incidence was consistently higher and remained substantial (5.3 per 1000 person-years) at 24 months and longer after starting cART. The strongest independent risk factors for tuberculosis after cART start were most recent CD4 cell count: adjusted rate ratios (aRR) 10.65 (95% CI 6.11, 18.57), 3.40 (95% CI 2.05, 5.65), 1.77 (95% CI 1.06, 2.96) and 1.84 (95% CI 1.09, 3.12) for individuals with CD4 cell counts less than 50, 50-199, 200-349 and 350-499 cells/microl, respectively, compared with at least 500 cells/microl; and black African vs. white ethnicity [aRR 2.93 (95% CI 1.89, 4.54)]. HIV risk group, shorter time on cART, later calendar period and unsuppressed viral load were also independently associated with incident tuberculosis. CONCLUSIONS Tuberculosis incidence among people attending UK HIV clinics is substantial, particularly among those with non-white ethnicity and low CD4 cell counts, even after starting cART. Earlier HIV diagnosis is needed in order to implement interventions to prevent tuberculosis; tuberculosis preventive therapy should be considered in addition to cART.
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Houben RMGJ, Glynn JR. A systematic review and meta-analysis of molecular epidemiological studies of tuberculosis: development of a new tool to aid interpretation. Trop Med Int Health 2009; 14:892-909. [DOI: 10.1111/j.1365-3156.2009.02316.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Achonu C, Jamieson F, Behr MA, Lillebaek T, Khan K, Gardam M. Evidence for local transmission and reactivation of tuberculosis in the Toronto Somali community. ACTA ACUST UNITED AC 2009; 38:778-81. [PMID: 16938731 DOI: 10.1080/00365540600664084] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
To further understand the molecular and clinical epidemiology of tuberculosis in the Toronto Somali community, molecular fingerprinting using IS6110 restriction fragment length polymorphism typing or spoligotyping was performed on M. tuberculosis isolates obtained from Somali-Canadians who developed active disease from 1997 to 2001. Molecular fingerprints were further compared with those obtained from Somalis residing in Denmark. 142 Somali TB patients were reported, for whom, 80 isolates were fingerprinted. 25% of isolates were clustered. Three clusters involving 2 patients each were identified out of the17 isolates that underwent spoligotyping. Of the 63 isolates typed by the IS6110 method, 6 clusters (4 of 2 patients and 2 of 3 patients) were identified. 57% of these isolates were found to be identical to Danish isolates. Our study suggests that a combination of reactivation and recent transmission are responsible for the high incidence rates of tuberculosis in this community. We recommend that ongoing surveillance and treatment programmes be directed towards this community.
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Dandoulakis M, Roussos N, Karageorgopoulos DE, Yatromanolakis N, Falagas ME. Trends of tuberculin skin test positivity rate among schoolchildren in Attica, Greece. ACTA ACUST UNITED AC 2009; 41:195-200. [DOI: 10.1080/00365540902721392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Tardin A, Dominicé Dao M, Ninet B, Janssens JP. Tuberculosis cluster in an immigrant community: case identification issues and a transcultural perspective. Trop Med Int Health 2009; 14:995-1002. [PMID: 19563432 DOI: 10.1111/j.1365-3156.2009.02325.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES In a low incidence area for tuberculosis (TB), a computerized database identified an unusually high proportion of patients coming from one single country between 2004 and 2006. To determine whether they constituted a cluster, whether clustering was due to recent transmission, and to understand what undermined the efficacy of the contact tracing procedure, we conducted a retrospective study of all patients with TB from this country. METHODS Mycobacterium tuberculosis isolates of 15 TB cases originating from the same country over a 2(1/2) year period were analysed by restriction fragment length polymorphism (RFLP) and/or Rep-PCR. To identify links between patients, we revisited the social worker's files, cross-matched contacts' databases, and performed internet searches. A cultural evaluation was conducted by an anthropologist and an expert physician, through patient and community key informant interviews and a literature review. RESULTS Genotyping confirmed that 11 of 15 patients had identical isolates. Additional data revealed an unsuspected complex network of social links between 9 of these 11 patients. The transcultural evaluation pointed out the major obstacles to efficient contact tracing, such as importance of social stigma related to TB, differences in communication style and health beliefs, and linguistic barriers. CONCLUSION The combined finding of identical genotypes and important social links between patients confirmed the suspicion of a TB cluster due to recent transmission. The cultural evaluation helped to explain the difficulties encountered during the contact tracing procedure, and offered strategies to improve its efficacy despite the magnitude of the social stigma attached to TB in this community.
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Affiliation(s)
- A Tardin
- Tropical Medicine Unit, Division of International and Humanitarian Health, Geneva University Hospitals, Switzerland.
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Bodenmann P, Vaucher P, Wolff H, Favrat B, de Tribolet F, Masserey E, Zellweger JP. Screening for latent tuberculosis infection among undocumented immigrants in Swiss healthcare centres; a descriptive exploratory study. BMC Infect Dis 2009; 9:34. [PMID: 19317899 PMCID: PMC2667187 DOI: 10.1186/1471-2334-9-34] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Accepted: 03/24/2009] [Indexed: 12/04/2022] Open
Abstract
Background Migration is one of the major causes of tuberculosis in developed countries. Undocumented patients are usually not screened at the border and are not covered by a health insurance increasing their risk of developing the disease unnoticed. Urban health centres could help identify this population at risk. The objective of this study is to assess the prevalence of latent tuberculosis infection (LTBI) and adherence to preventive treatment in a population of undocumented immigrant patients. Methods All consecutive undocumented patients that visited two urban healthcare centres for vulnerable populations in Lausanne, Switzerland for the first time were offered tuberculosis screening with an interferon-γ assay. Preventive treatment was offered if indicated. Adherence to treatment was evaluated monthly over a nine month period. Results Of the 161 participants, 131 (81.4%) agreed to screening and 125 had complete examinations. Twenty-four of the 125 patients (19.2%; CI95% 12.7;27.2) had positive interferon-γ assay results, two of which had active tuberculosis. Only five patients with LTBI completed full preventive treatments. Five others initiated the treatment but did not follow through. Conclusion Screening for tuberculosis infection in this hard-to-reach population is feasible in dedicated urban clinics, and the prevalence of LTBI is high in this vulnerable population. However, the low adherence to treatment is an important public health concern, and new strategies are needed to address this problem.
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Affiliation(s)
- Patrick Bodenmann
- Department of Ambulatory Care and Community Medicine, University of Lausanne, Switzerland.
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Alner JM, Hagen D, Andrews S, Loveday R, van Woerden HC. Are residential and nursing homes adequately screening overseas healthcare workers? BMC Res Notes 2008; 1:62. [PMID: 18710515 PMCID: PMC2527002 DOI: 10.1186/1756-0500-1-62] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 08/05/2008] [Indexed: 12/01/2022] Open
Abstract
Background There has been significant growth in the number of healthcare workers born outside the UK or recruited to the UK from countries with a high prevalence of TB, Hepatitis and other blood borne infections. Government policy recognises the need for occupational health procedures to facilitate treatment for these individuals and to reduce the risk of transmission of disease to patients. The aim of this study was to undertake a survey of nursing and residential homes in South East England, to assess whether homes had occupational health screening policies for healthcare workers who have originated from overseas, and what level of occupational health screening had been undertaken on these employees. Methods An anonymous survey was sent to all 500 homes in West Sussex assessing occupational health practices for "overseas health care workers", defined as health care workers who had been born outside the UK. Results Only one employer (0.8%) reported they had an occupational health screening policy specific for healthcare workers who originate from overseas. Over 80% of homes who had recruited directly had no evidence of screening results for HIV, TB, Hepatitis B and C. The commonest countries of origin for staff were the UK, Philippines, Poland, South Africa, Zimbabwe, and India. Conclusion This study suggests that screening of overseas healthcare workers is not routine practice for residential or nursing care homes and requires further input from Primary Care Trust's, Health Care Commission, Commission for Social Care Inspection, and Professional bodies.
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Affiliation(s)
- Joanne M Alner
- Public Health Department, Wandsworth Teaching PCT, Lupin Ward, Jasmine Tower, Springfield University Hospital, 61 Glenburnie Rd, London SW17 7DJ, UK.
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Akhtar S, Mohammad HGHH. Nonlinear pattern of pulmonary tuberculosis among migrants at entry in Kuwait: 1997-2006. BMC Public Health 2008; 8:264. [PMID: 18667057 PMCID: PMC2527606 DOI: 10.1186/1471-2458-8-264] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 07/30/2008] [Indexed: 12/04/2022] Open
Abstract
Background There is a paucity of published data on the pattern of pulmonary tuberculosis among migrant workers entering Middle Eastern countries particularly Kuwait. The objectives of this study were to use routine health surveillance data i) to estimate the prevalence of pulmonary tuberculosis among migrant workers at entry in Kuwait and ii) to determine the occurrence of any time trends in the proportions of pulmonary tuberculosis positive workers over the study period. Methods The monthly aggregates of daily number of migrants tested and the number of pulmonary tuberculosis cases detected during routine health examinations of migrant workers from tuberculosis high-prevalence countries were used to generate the monthly series of proportions (per 100,000) of pulmonary tuberculosis cases over 120 months between January 1, 1997 and December 31, 2006 and analysed using time series methods. Results The overall prevalence (per 100,000) of documented pulmonary tuberculosis cases among screened migrants was 198 (4608/2328582). Year-specific prevalence (per 100,000) of tuberculosis cases consistently declined from 456 (95% CI: 424 – 490) in 1997 to 124 (95% CI: 110 – 140) in 2002 before showing a steady increase up to 183 (95% CI: 169–197) in 2006. The second-order polynomial regression model revealed significant (P < 0.001) initial decline, followed by a significant (P < 0.001) increasing trend thereafter in monthly proportions of tuberculosis cases among migrant workers. Conclusion The proportions of documented tuberculosis cases among migrant workers showed a significant nonlinear pattern, with an initial decline followed by a significant increasing trend towards the end of the study period. These findings underscore the need to maintain the current policy of migrants' screening for tuberculosis at entry. The public health authorities in Kuwait and perhaps other countries in the region may consider complementing the current screening protocol with interferon-γ assays to detect migrants with latent Mycobacterium tuberculosis infection. An appropriate curative or preventive chemotherapy of detected tuberculosis cases may help in further minimizing the risk of local transmission of M. tuberculosis, while contributing in global efforts to control this public health menace.
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Affiliation(s)
- Saeed Akhtar
- Department of Community Medicine and Behavioural Sciences, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110, Kuwait.
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Crofts JP, Gelb D, Andrews N, Delpech V, Watson JM, Abubakar I. Investigating tuberculosis trends in England. Public Health 2008; 122:1302-10. [PMID: 18672258 DOI: 10.1016/j.puhe.2008.04.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 12/07/2007] [Accepted: 04/16/2008] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To investigate the factors associated with the increasing incidence of tuberculosis in England. DESIGN Prospective national surveillance study. METHODS Measurement of relative trends in demographic, clinical and microbiological characteristics of tuberculosis cases reported in England between 1999 and 2003. RESULTS Between 1999 and 2003, the number of tuberculosis cases reported in England increased by 19% from 5539 to 6608. Significant increases in tuberculosis cases were seen in the non-UK-born population who were recent entrants to the UK (arrival less than 5 years prior to diagnosis) relative to cases in the UK-born population, both in London [1.08; 95% confidence interval (CI) 1.02-1.14] and outside London (1.22; 95% CI 1.16-1.28). Cases of tuberculosis co-infected with human immunodeficiency virus (HIV) increased significantly both in London (1.19; 95% CI 1.12-1.27) and outside London (1.22; 95% CI 1.12-1.33) relative to cases not known to be co-infected with HIV. Small increases in the number of cases living in less-deprived areas were observed relative to those in the most-deprived areas (1.11; 95% CI 1.02-1.21) in London. The number of cases of isoniazid-resistant (1.09; 95% CI 1.02-1.16) and multi-drug-resistant tuberculosis (1.22; 95% CI 1.02-1.45) increased relative to drug-susceptible cases in London. CONCLUSIONS Tuberculosis remains strongly associated with deprivation, but no real change in the distribution of tuberculosis cases by deprivation was observed over the study period. The proportion of tuberculosis cases co-infected with HIV has increased, but migration explains most of the recent trends in tuberculosis in England. Measures that target latent tuberculosis infection could have an increased role to play alongside measures against active disease in reducing the incidence of tuberculosis in the UK.
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Affiliation(s)
- J P Crofts
- Respiratory Diseases Department, Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK
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Comparison of mycobacterial interspersed repetitive unit-variable number tandem repeat and IS6110-RFLP methods in identifying epidemiological links in patients with tuberculosis in Northwest of Iran. ANN MICROBIOL 2008. [DOI: 10.1007/bf03175339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Dahle UR, Eldholm V, Winje BA, Mannsåker T, Heldal E. Impact of immigration on the molecular epidemiology of Mycobacterium tuberculosis in a low-incidence country. Am J Respir Crit Care Med 2007; 176:930-5. [PMID: 17673698 DOI: 10.1164/rccm.200702-187oc] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Programs to prevent the incidence rate of tuberculosis (TB) from increasing in many low-incidence countries are challenged by international travel and immigration from high-burden countries. OBJECTIVES The current study aimed to determine the effect of such immigration on the genetic diversity of Mycobacterium tuberculosis isolates in an entire nation's population during 1994-2005. METHODS A total of 3,131 patients were notified with TB during the 12-year period. Of these, 2,284 (73%) had TB verified by culture, and isolates from 2,173 (96%) of these were analyzed by IS6110 restriction fragment length polymorphism. MEASUREMENTS AND MAIN RESULTS Only 31% of the included strains were isolated from nonimmigrants, the remaining 69% were isolated from immigrants. Although the incidence increased throughout the period, the genetic diversity remained high. A total of 135 clusters were identified; the percentage of recent disease was reduced among nonimmigrants, and remained stable among the immigrants during the study period. Although 69% of the isolates originated from immigrants from high-incidence countries, the established TB control program in the receiving country was adequate for the prevention of disease transmission. On average per year, only 2 nonimmigrants and 13 immigrants developed disease as a result of infection within the country by imported M. tuberculosis. CONCLUSIONS Twelve years of M. tuberculosis importation as a result of immigration from high-incidence countries had little influence on the transmission of this pathogen in the receiving low-incidence country. To prevent future increase of transmission of TB, the current control strategies of low-incidence countries are adequate but must be maintained.
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Affiliation(s)
- Ulf R Dahle
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway.
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Affiliation(s)
- Tony Walls
- Great Ormond Street Hospital for Children, Great Ormond Street, London, UK
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Griffiths C, Sturdy P, Brewin P, Bothamley G, Eldridge S, Martineau A, MacDonald M, Ramsay J, Tibrewal S, Levi S, Zumla A, Feder G. Educational outreach to promote screening for tuberculosis in primary care: a cluster randomised controlled trial. Lancet 2007; 369:1528-1534. [PMID: 17482983 DOI: 10.1016/s0140-6736(07)60707-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Tuberculosis is re-emerging as an important health problem in industrialised countries. Uncertainty surrounds the effect of public-health control options. We therefore aimed to assess a programme to promote screening for tuberculosis in a UK primary health care district. METHODS In a cluster randomised controlled trial, we randomised 50 of 52 (96%) eligible general practices in Hackney, London, UK, to receive an outreach programme that promoted screening for tuberculosis in people registering in primary care, or to continue with usual care. Screening was verbal, and proceeded to tuberculin skin testing, if appropriate. The primary outcome was the proportion of new cases of active tuberculosis identified in primary care. Analyses were done on an intention-to-treat basis. This study was registered at clinicaltrials.gov, number NCT00214708. FINDINGS Between June 1, 2002, and Oct 1, 2004, 44,986 and 48,984 patients registered with intervention and control practices, respectively. In intervention practices 57% (13,478 of 23,573) of people attending a registration health check were screened for tuberculosis compared with 0.4% (84 of 23 051) in control practices. Intervention practices showed increases in the diagnosis of active tuberculosis cases in primary care compared with control practices (66/141 [47%] vs 54/157 [34%], odds ratio (OR) 1.68, 95% CI 1.05-2.68, p=0.03). Intervention practices also had increases in diagnosis of latent tuberculosis (11/59 [19%] vs 5/68 [9%], OR 3.00, 0.98-9.20, p=0.055) and BCG coverage (mean BCG rate 26.8/1000 vs 3.8/1000, intervention rate ratio 9.52, 4.0-22.7, p<0.001). INTERPRETATION Our educational intervention for promotion of screening for tuberculosis in primary care improved identification of active and latent tuberculosis, and increased BCG coverage. Yield from screening was low, but was augmented by improved case-finding. Screening programmes in primary care should be considered as part of tuberculosis control initiatives in industrialised countries.
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Affiliation(s)
- Chris Griffiths
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK; Lower Clapton Group Practice, Lower Clapton Road, Hackney, UK; MRC and Asthma UK Centre in Allergic Mechanisms of Asthma, King's College London School of Medicine, Guy's Hospital, St. Thomas' Street, London SE1 9RT, UK.
| | - Pat Sturdy
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK; Lower Clapton Group Practice, Lower Clapton Road, Hackney, UK
| | - Penny Brewin
- Department of Respiratory Medicine, Homerton University Hospital, Homerton Row, London, UK; Lower Clapton Group Practice, Lower Clapton Road, Hackney, UK
| | - Graham Bothamley
- Department of Respiratory Medicine, Homerton University Hospital, Homerton Row, London, UK
| | - Sandra Eldridge
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK
| | - Adrian Martineau
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK
| | - Meg MacDonald
- Lower Clapton Group Practice, Lower Clapton Road, Hackney, UK
| | - Jean Ramsay
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK
| | | | - Sue Levi
- City & Hackney Teaching Primary Care Trust, St. Leonard's Hospital, London
| | - Ali Zumla
- Centre for Infectious Diseases & International Health, Windeyer Building, Cleveland Street, London
| | - Gene Feder
- Centre for Health Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London, UK; Lower Clapton Group Practice, Lower Clapton Road, Hackney, UK
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Sintchenko V, Gilbert GL. Utility of genotyping of Mycobacterium tuberculosis in the contact investigation: A decision analysis. Tuberculosis (Edinb) 2007; 87:176-84. [DOI: 10.1016/j.tube.2006.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Revised: 10/18/2006] [Accepted: 10/25/2006] [Indexed: 10/23/2022]
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Brown M, Varia H, Bassett P, Davidson RN, Wall R, Pasvol G. Prospective study of sputum induction, gastric washing, and bronchoalveolar lavage for the diagnosis of pulmonary tuberculosis in patients who are unable to expectorate. Clin Infect Dis 2007; 44:1415-20. [PMID: 17479935 DOI: 10.1086/516782] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Accepted: 02/12/2007] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Many adults with pulmonary tuberculosis are unable to expectorate. Gastric washing, sputum induction using nebulized hypertonic saline, and bronchoscopy with bronchoalveolar lavage have all been used to obtain specimens for diagnosis, but to our knowledge, the timing and volume of induced sputum have not been well studied, and these 3 methods have not been compared. METHODS The study recruited consecutive adult inpatients with chest radiography findings suggestive of tuberculosis who were unable to expectorate. Subjects provided 3 induced sputum samples for culture on day 1 and additional samples on days 2 and 3. In addition, gastric washing specimens were collected on days 1, 2, and 3. A proportion of subjects with negative smear results underwent bronchoalveolar lavage. RESULTS The study recruited 140 subjects. Among 107 subjects who provided 3 gastric washing specimens and at least 3 induced sputum specimens, 43% had cultures positive for Mycobacterium tuberculosis. Use of 3 induced sputum samples detected more cases than did use of 3 gastric washings (39% vs. 30%; P=.03). Among 79 subjects with culture results for all 5 induced sputum specimens, there was no difference in yield between samples obtained by induced sputum induction performed in a single day or that performed over 3 days (34% vs. 37%; P=.63). There was no association between sputum volume and positive culture results. No additional cases were diagnosed in the 21 patients who underwent bronchoscopy. CONCLUSIONS Use of 3 induced sputum samples was more sensitive than use of 3 gastric washings for diagnosis of tuberculosis in patients who could not expectorate spontaneously. Use of bronchoscopy with bronchoalveolar lavage did not increase diagnostic sensitivity. Samples could be collected in 1 day, allowing for faster diagnosis, faster initiation of treatment, and shorter hospital stay.
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Affiliation(s)
- Michael Brown
- Department of Infection and Tropical Medicine, Lister Unit, Northwick Park Hospital, Harrow, Middlesex, United Kingdom.
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Asgharzade M, Shahbabian K, Samadi Kaf H, Rafi A. Use of DNA Fingerprinting in Identifying the Source Case of Tuberculosis in East Azarbaijan Province of Iran. JOURNAL OF MEDICAL SCIENCES 2007. [DOI: 10.3923/jms.2007.418.421] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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