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Gutierrez J, Nsereko M, Malone LL, Mayanja-Kizza H, Kisingo H, Boom WH, Bark CM, Stein CM. Capturing Recent Mycobacterium tuberculosis Infection by Tuberculin Skin Test vs. Interferon-Gamma Release Assay. Trop Med Infect Dis 2024; 9:81. [PMID: 38668542 PMCID: PMC11053984 DOI: 10.3390/tropicalmed9040081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/27/2024] [Accepted: 04/09/2024] [Indexed: 04/29/2024] Open
Abstract
Reductions in tuberculosis (TB) incidence require identification of individuals at high risk of developing active disease, such as those with recent Mycobacterium tuberculosis (Mtb) infection. Using a prospective household contact (HHC) study in Kampala, Uganda, we diagnosed new Mtb infection using both the tuberculin skin test (TST) and interferon-gamma release assay (IGRA). Our study aimed to determine if the TST adds additional value to the characterization of IGRA converters. We identified 13 HHCs who only converted the IGRA (QFT-only converters), 39 HHCs who only converted their TST (TST-only converters), and 24 HHCs who converted both tests (QFT/TST converters). Univariate analysis revealed that TST-only converters were older. Additionally, increased odds of TST-only conversion were associated with older age (p = 0.02) and crowdedness (p = 0.025). QFT/TST converters had higher QFT quantitative values at conversion than QFT-only converters and a bigger change in TST quantitative values at conversion than TST-only converters. Collectively, these data indicate that TST conversion alone likely overestimates Mtb infection. Its correlation to older age suggests an "environmental" boosting response due to prolonged exposure to environmental mycobacteria. This result also suggests that QFT/TST conversion may be associated with a more robust immune response, which should be considered when planning vaccine studies.
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Affiliation(s)
- Jesús Gutierrez
- Department of Population and Quantitative Health Science, Case Western Reserve University, Cleveland, OH 44106, USA;
| | - Mary Nsereko
- Uganda-CWRU Research Collaboration and Department of Medicine, School of Medicine, Makerere University, Kampala 7062, Uganda; (M.N.); (H.M.-K.); (H.K.)
| | - LaShaunda L. Malone
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA (W.H.B.)
| | - Harriet Mayanja-Kizza
- Uganda-CWRU Research Collaboration and Department of Medicine, School of Medicine, Makerere University, Kampala 7062, Uganda; (M.N.); (H.M.-K.); (H.K.)
| | - Hussein Kisingo
- Uganda-CWRU Research Collaboration and Department of Medicine, School of Medicine, Makerere University, Kampala 7062, Uganda; (M.N.); (H.M.-K.); (H.K.)
| | - W. Henry Boom
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA (W.H.B.)
| | - Charles M. Bark
- Division of Infectious Diseases, MetroHealth Medical Center, Cleveland, OH 44109, USA;
| | - Catherine M. Stein
- Department of Population and Quantitative Health Science, Case Western Reserve University, Cleveland, OH 44106, USA;
- Department of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA (W.H.B.)
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2
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Miles TT, Riley-Powell AR, Lee GO, Gotlieb EE, Barth GC, Tran EQ, Ortiz K, Huaynate CA, Cabrera L, Gravitt PE, Oberhelman RA, Paz-Soldan VA. Knowledge, attitudes, and practices of cervical cancer prevention and pap smears in two low-income communities in Lima, Peru. BMC Womens Health 2021; 21:168. [PMID: 33882904 PMCID: PMC8059236 DOI: 10.1186/s12905-021-01291-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 03/30/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cervical cancer is a leading cause of death among Peruvian women. Barriers at multiple levels impact effective screening and treatment, including a lack of knowledge about cervical cancer and how regular screening can reduce morbidity and mortality through earlier detection. The aim of this study is to assess knowledge, attitudes, and practices regarding cervical cancer and its prevention in the peri-urban communities of Oasis and Pampas in southern Lima, Peru that can be used to inform future campaigns about cervical cancer prevention. METHODS A cross-sectional survey that included several open-ended questions was administered to women in Pampas and Oasis between 2015 and 2016 to evaluate the knowledge, attitudes, and practices regarding cervical cancer and Pap smears. RESULTS In total, 224 women were interviewed. Knowledge about cervical cancer and Pap smears was high, and attitudes were predominantly positive among most participants. Most participants knew how often they should get Pap smears (89.7%), when to begin seeking screening (74.6%), knew the price of a Pap smear (61.9%), and felt Pap smears were important for their health (70.1%). About one third (29.5%) of premenopausal women reported receiving a Pap smear in the last year. However, open ended questions revealed some knowledge gaps around Pap smears, as well as some stigma associated to Human Papilloma Virus (HPV) infection. CONCLUSION Although knowledge of cervical cancer prevention was generally high and perceptions were positive among women in peri-urban Peruvian communities, our findings revealed there is a need for education on HPV infection prevalence among sexually active individuals to reduce stigma. Future research should focus on exploring experiences with follow-up and treatment associated with abnormal Pap smears, as well as perspectives from health authorities and professionals about barriers in the early detection and treatment process for cervical cancer.
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Affiliation(s)
- Thomas T Miles
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Amy R Riley-Powell
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Gwenyth O Lee
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
- Department of Epidemiology, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI, 48109-2029, USA
| | - Esther E Gotlieb
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Gabriela C Barth
- Tulane University, 6823 St Charles Ave, New Orleans, LA, 70118, USA
| | - Emma Q Tran
- Tulane University, 6823 St Charles Ave, New Orleans, LA, 70118, USA
| | - Katherine Ortiz
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Cynthia Anticona Huaynate
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Lilia Cabrera
- Asociación Benéfica PRISMA, Lima, Peru - Carlos Gonzales 251, San Miguel, 15088, USA
| | - Patti E Gravitt
- Department of Epidemiology and Public Health, School of Medicine, University of Maryland, Baltimore, 655 W. Baltimore Street, Baltimore, MD, 21201, USA
| | - Richard A Oberhelman
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA
| | - Valerie A Paz-Soldan
- Global Community Health and Behavioral Sciences Department, Tulane University School of Public Health and Tropical Medicine, 1440 Canal St., Suite 2200, New Orleans, LA, 70112, USA.
- Asociación Benéfica PRISMA, Lima, Peru - Carlos Gonzales 251, San Miguel, 15088, USA.
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3
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Cords O, Martinez L, Warren JL, O'Marr JM, Walter KS, Cohen T, Zheng J, Ko AI, Croda J, Andrews JR. Incidence and prevalence of tuberculosis in incarcerated populations: a systematic review and meta-analysis. LANCET PUBLIC HEALTH 2021; 6:e300-e308. [PMID: 33765455 PMCID: PMC8168455 DOI: 10.1016/s2468-2667(21)00025-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/17/2020] [Accepted: 01/25/2021] [Indexed: 12/24/2022]
Abstract
Background Prisons are recognised as high-risk environments for tuberculosis, but there has been little systematic investigation of the global and regional incidence and prevalence of tuberculosis, and its determinants, in prisons. We did a systematic review and meta-analysis to assess the incidence and prevalence of tuberculosis in incarcerated populations by geographical region. Methods In this systematic review and meta-analysis, we searched MEDLINE, Embase, Web of Knowledge, and the LILACS electronic database from Jan 1, 1980, to Nov 15, 2020, for cross-sectional and cohort studies reporting the incidence of Mycobacterium tuberculosis infection, incidence of tuberculosis, or prevalence of tuberculosis among incarcerated individuals in all geographical regions. We extracted data from individual studies, and calculated pooled estimates of incidence and prevalence through hierarchical Bayesian meta-regression modelling. We also did subgroup analyses by region. Incidence rate ratios between prisons and the general population were calculated by dividing the incidence of tuberculosis in prisons by WHO estimates of the national population-level incidence. Findings We identified 159 relevant studies; 11 investigated the incidence of M tuberculosis infection (n=16 318), 51 investigated the incidence of tuberculosis (n=1 858 323), and 106 investigated the prevalence of tuberculosis (n=6 727 513) in incarcerated populations. The overall pooled incidence of M tuberculosis infection among prisoners was 15·0 (95% credible interval [CrI] 3·8–41·6) per 100 person-years. The incidence of tuberculosis (per 100 000 person-years) among prisoners was highest in studies from the WHO African (2190 [95% CrI 810–4840] cases) and South-East Asia (1550 [240–5300] cases) regions and in South America (970 [460–1860] cases), and lowest in North America (30 [20–50] cases) and the WHO Eastern Mediterranean region (270 [50–880] cases). The prevalence of tuberculosis was greater than 1000 per 100 000 prisoners in all global regions except for North America and the Western Pacific, and highest in the WHO South-East Asia region (1810 [95% CrI 670–4000] cases per 100 000 prisoners). The incidence rate ratio between prisons and the general population was much higher in South America (26·9; 95% CrI 17·1–40·1) than in other regions, but was nevertheless higher than ten in the WHO African (12·6; 6·2–22·3), Eastern Mediterranean (15·6; 6·5–32·5), and South-East Asia (11·7; 4·1–27·1) regions. Interpretation Globally, people in prison are at high risk of contracting M tuberculosis infection and developing tuberculosis, with consistent disparities between prisons and the general population across regions. Tuberculosis control programmes should prioritise preventive interventions among incarcerated populations. Funding US National Institutes of Health.
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Affiliation(s)
- Olivia Cords
- Division of Infectious Diseases and Geographic Medicine, Stanford, CA, USA
| | - Leonardo Martinez
- Division of Infectious Diseases and Geographic Medicine, Stanford, CA, USA; Department of Epidemiology, School of Public Health, Boston University, Boston, MA, USA.
| | - Joshua L Warren
- Department of Biostatistics, Yale School of Public Health, New Haven, CT, USA
| | - Jamieson Michael O'Marr
- Division of Infectious Diseases and Geographic Medicine, Stanford, CA, USA; Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Katharine S Walter
- Division of Infectious Diseases and Geographic Medicine, Stanford, CA, USA
| | - Ted Cohen
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA
| | - Jimmy Zheng
- Stanford University School of Medicine, Stanford, CA, USA
| | - Albert I Ko
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA; Oswaldo Cruz Foundation, Salvador, Brazil
| | - Julio Croda
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, USA; Universidade Federal de Mato Grosso do Sul, Faculdade de Medicina, Campo Grande, Mato Grosso do Sul, Brazil; Fundação Oswaldo Cruz, Campo Grande, Mato Grosso do Sul, Brazil
| | - Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford, CA, USA
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Bustamante-Rengifo JA, González-Salazar LÁ, Osorio-Certuche N, Bejarano-Lozano Y, Tovar Cuevas JR, Astudillo-Hernández M, Crespo-Ortiz MDP. Prevalence of and risk factors associated with latent tuberculosis infection in a Latin American region. PeerJ 2020. [DOI: 10.7717/peerj.9429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tuberculosis (TB) represents a health problem in Colombia, and its control is focused on the search for contacts and treatment of TB cases underscoring the role of latent tuberculosis infection (LTBI) as a reservoir of Mycobacterium tuberculosis. The burden of LTBI in Colombia is unknown. We aimed to estimate the prevalence of LTBI and identify the associated risk factors. In this cross-sectional study, we recruited participants from four health care centers in Cali, Colombia. The participants were eligible if they were aged between 14 and 70 years, and all participants answered a survey evaluating their medical history and sociodemographic and lifestyle factors. LTBI status was based on tuberculin skin test (TST) positivity using two thresholds: ≥10 mm (TST-10) and ≥15 mm (TST-15). The magnitude of the associations between independent factors and dependent outcomes (LTBI status and TST induration) were evaluated by logistic regression and generalized linear models, respectively. A total of 589 individuals were included with TST positivity rates of 25.3% (TST-10) and 13.2% (TST-15). Logistic regression showed that being between age 40 and 69 years (OR = 7.28, 95% CI [1.62–32.7]), being male (OR = 1.71, 95% CI [1.04–2.84]), being employed (OR = 1.56, 95% CI [1.02–2.38]), and having a low intake of alcohol (OR = 2.40, 95% CI [1.13–5.11]) were risk factors for TST positivity, while living in the north zone (OR = 0.32, 95% CI [0.18–0.55]), living in the suburb zone (OR = 0.28, 95% CI [0.15–0.52]) and having a secondary education (OR = 0.49 95% CI [0.29–0.83]) lowered the risk of TST positivity. The generalized linear model showed that the previous predictors, as well as a low body mass index, had an effect on TST reaction size. The LTBI prevalence found in the population was moderate, reflecting the continuous transmission of M. tuberculosis. Social factors seem to play a decisive role in the risk of LTBI. Employed males, who are over 40 years of age, are overweight, have a lower level of education and have a low intake of alcohol (50–100 mL, once/week) should be a priority group for prophylactic treatment as a strategy for TB control in this city.
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Affiliation(s)
| | - Luz Ángela González-Salazar
- Biotechnology and Bacterial Infections Group, Department of Microbiology, Universidad del Valle, Cali, Colombia
| | - Nicole Osorio-Certuche
- Biotechnology and Bacterial Infections Group, Department of Microbiology, Universidad del Valle, Cali, Colombia
| | | | | | - Miryam Astudillo-Hernández
- Biotechnology and Bacterial Infections Group, Department of Microbiology, Universidad del Valle, Cali, Colombia
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Martinez L, Woldu H, Chen C, Hallowell BD, Castellanos ME, Lu P, Liu Q, Whalen CC, Zhu L. Transmission Dynamics in Tuberculosis Patients with Human Immunodeficiency Virus: A Systematic Review and Meta-Analysis of 32 Observational Studies. Clin Infect Dis 2020; 73:e3446-e3455. [PMID: 32770236 DOI: 10.1093/cid/ciaa1146] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND There are large knowledge gaps on the transmission dynamics of Mycobacterium tuberculosis in settings where both tuberculosis and HIV are endemic. We aimed to assess the infectiousness of tuberculosis patients coinfected with HIV. METHODS We systematically searched for studies of contacts of both HIV-positive and negative tuberculosis index cases. Our primary outcome was Mycobacterium tuberculosis infection in contacts. Data on sputum smear and lung cavitation status of index cases was extracted from each study to assess effect modification. Secondary outcomes included prevalent tuberculosis and HIV in contacts of HIV-positive and negative index cases. RESULTS Of 5,255 original citations identified, 32 studies met inclusion criteria including 25 studies investigating M. tuberculosis infection (Nparticipants=36,893), 13 on tuberculosis (Nparticipants=18,853), and 12 on HIV positivity (Nparticipants=18,424). Risk of M. tuberculosis infection was lower in contacts of HIV-positive index cases (Odds Ratio [OR], 0.67, 95% CI, 0.58-0.77) but was heterogeneous (I2=75.1%). Two factors modified this relationship: the lung cavitary status of the index case and immunosuppression (measured through CD4 counts or HIV or AIDS diagnoses) among index patients living with HIV. Rates of HIV were consistently higher in contacts of coinfected index cases (OR, 4.9, 95% CI, 3.0-8.0). This was modified by whether the study was in sub-Saharan Africa (OR, 2.8, 1.6-4.9) or in another global region (OR, 9.8, 5.9-16.3). CONCLUSIONS Tuberculosis patients coinfected with HIV are less infectious than HIV-uninfected cases when they have severe immunosuppression or paucibacillary disease. Contacts of coinfected index cases are almost five times more likely to also have HIV.
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Affiliation(s)
- Leonardo Martinez
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia, United States.,Center for Global Health, College of Public Health, University of Georgia, Athens, Georgia, United States.,Stanford University, School of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford, USA
| | - Henok Woldu
- Biostatistics & Research Design Unit School of Medicine, University of Missouri-Columbia, Columbia, Missouri
| | - Cheng Chen
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China.,Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China.,School of Public Health, Fudan University, Shanghai, China
| | - Benjamin D Hallowell
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia, United States.,Center for Global Health, College of Public Health, University of Georgia, Athens, Georgia, United States
| | - Maria Eugenia Castellanos
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia, United States.,Center for Global Health, College of Public Health, University of Georgia, Athens, Georgia, United States
| | - Peng Lu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Qiao Liu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Christopher C Whalen
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia, United States.,Center for Global Health, College of Public Health, University of Georgia, Athens, Georgia, United States
| | - Limei Zhu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
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6
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Wong YJ, Lee SWH. Prevalence of latent tuberculosis among refugee children in Malaysia. ERJ Open Res 2020; 6:00254-2019. [PMID: 32166089 PMCID: PMC7061204 DOI: 10.1183/23120541.00254-2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/12/2020] [Indexed: 12/14/2022] Open
Abstract
Introduction Tuberculosis remains one of the top 10 major causes of global mortality, imposing social-economic and medical challenges in Malaysia. Refugees sheltered in Malaysia are a high-risk population but basic health checks upon their arrival, including tuberculosis screening, are not practised. This study aimed to identify the prevalence and risk factors of tuberculosis and latent tuberculosis infection (LTBI) among refugee children in Malaysia. Methods A cross-sectional study was performed in three refugee schools in the Klang Valley, Malaysia, using tuberculin skin tests or interferon-γ release assays. Participants who tested positive were sent for further examination with chest radiography to confirm the tuberculosis diagnosis. Results From April 2018 to April 2019, we screened 430 refugee children with a median age of 13.0 years. Most of the children were born in Myanmar (n=274, 63.7%) and Pakistan (n=60, 14.0%). No children were diagnosed with active tuberculosis but 55 of the children (12.8%) were diagnosed with LTBI. Children with LTBI were generally older (OR 3.01, 95% CI 1.71-5.29; p<0.001) than those without LTBI infection. Sex, history of bacille Calmette-Guérin vaccination and country of birth were not associated with increased risk of LTBI. Conclusion The relatively high LTBI burden among refugee children in this study poses an indication of possible LTBI risk among this population nationwide, and thus would be an important group to target for preventive therapy. This provides a unique opportunity for researchers to further examine and implement well-structured preventive strategies in combating the endemic infectious disease in Malaysia.
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Affiliation(s)
- Yen Jun Wong
- School of Pharmacy, Monash University Malaysia, Selangor, Malaysia
| | - Shaun Wen Huey Lee
- School of Pharmacy, Monash University Malaysia, Selangor, Malaysia.,Asian Centre for Evidence Synthesis in Population, Implementation and Clinical Outcomes, Health and Well-being Cluster, Global Asia in the 21st Century Platform, Monash University Malaysia, Selangor, Malaysia.,School of Pharmacy, Taylor's University Lakeside Campus, Selangor, Malaysia
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7
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Cohen A, Mathiasen VD, Schön T, Wejse C. The global prevalence of latent tuberculosis: a systematic review and meta-analysis. Eur Respir J 2019; 54:13993003.00655-2019. [PMID: 31221810 DOI: 10.1183/13993003.00655-2019] [Citation(s) in RCA: 262] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/11/2019] [Indexed: 12/18/2022]
Abstract
In 1999, the World Health Organization (WHO) estimated that one-third of the world's population had latent tuberculosis infection (LTBI), which was recently updated to one-fourth. However, this is still based on controversial assumptions in combination with tuberculin skin test (TST) surveys. Interferon-γ release assays (IGRAs) with a higher specificity than TST have since been widely implemented, but never used to estimate the global LTBI prevalence.We conducted a systematic review and meta-analysis of LTBI estimates based on both IGRA and TST results published between 2005 and 2018. Regional and global estimates of LTBI prevalence were calculated. Stratification was performed for low, intermediate and high TB incidence countries and a pooled estimate for each area was calculated using a random effects model.Among 3280 studies screened, we included 88 studies from 36 countries with 41 IGRA (n=67 167) and 67 TST estimates (n=284 644). The global prevalence of LTBI was 24.8% (95% CI 19.7-30.0%) and 21.2% (95% CI 17.9-24.4%), based on IGRA and a 10-mm TST cut-off, respectively. The prevalence estimates correlated well to WHO incidence rates (Rs=0.70, p<0.001).In the first study of the global prevalence of LTBI derived from both IGRA and TST surveys, we found that one-fourth of the world's population is infected. This is of relevance, as both tests, although imperfect, are used to identify individuals eligible for preventive therapy. Enhanced efforts are needed targeting the large pool of latently infected individuals, as this constitutes an enormous source of potential active tuberculosis.
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Affiliation(s)
- Adam Cohen
- Dept of Pathology, St Olavs Hospital, Trondheim, Norway.,Both authors contributed equally
| | - Victor Dahl Mathiasen
- International Reference Laboratory of Mycobacteriology, Statens Serum Institut, Copenhagen, Denmark.,Dept of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark.,Both authors contributed equally
| | - Thomas Schön
- Division of Microbiology and Molecular Medicine, Dept of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Dept of Clinical Microbiology and Infectious Diseases, Kalmar County Hospital, Kalmar, Linköping University, Linköping, Sweden
| | - Christian Wejse
- Dept of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark .,Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau.,Center for Global Health, Aarhus University (GloHAU), Aarhus, Denmark
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8
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Knight GM, Zimic M, Funk S, Gilman RH, Friedland JS, Grandjean L. The relative fitness of drug-resistant Mycobacterium tuberculosis: a modelling study of household transmission in Peru. J R Soc Interface 2019; 15:rsif.2018.0025. [PMID: 29950511 PMCID: PMC6030636 DOI: 10.1098/rsif.2018.0025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 06/05/2018] [Indexed: 12/22/2022] Open
Abstract
The relative fitness of drug-resistant versus susceptible bacteria in an environment dictates resistance prevalence. Estimates for the relative fitness of resistant Mycobacterium tuberculosis (Mtb) strains are highly heterogeneous and mostly derived from in vitro experiments. Measuring fitness in the field allows us to determine how the environment influences the spread of resistance. We designed a household structured, stochastic mathematical model to estimate the fitness costs associated with multidrug resistance (MDR) carriage in Mtb in Lima, Peru during 2010–2013. By fitting the model to data from a large prospective cohort study of TB disease in household contacts, we estimated the fitness, relative to susceptible strains with a fitness of 1, of MDR-Mtb to be 0.32 (95% credible interval: 0.15–0.62) or 0.38 (0.24–0.61), if only transmission or progression to disease, respectively, was affected. The relative fitness of MDR-Mtb increased to 0.56 (0.42–0.72) when the fitness cost influenced both transmission and progression to disease equally. We found the average relative fitness of MDR-Mtb circulating within households in Lima, Peru during 2010–2013 to be significantly lower than concurrent susceptible Mtb. If these fitness levels do not change, then existing TB control programmes are likely to keep MDR-TB prevalence at current levels in Lima, Peru.
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Affiliation(s)
- Gwenan M Knight
- National Institute of Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Imperial College London, Commonwealth Building, Hammersmith Campus, Du Cane Road, London W12 0NN, UK .,Infectious Diseases and Immunity, Imperial College London, Commonwealth Building, Hammersmith Campus, Du Cane Road, London W12 0NN, UK.,Centre for the Mathematical Modelling of Infectious Diseases, Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.,TB Centre, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Mirko Zimic
- Laboratorio de Bioinformática y Biología Molecular, Facultad de Ciencias, Universidad Peruana Cayetano Heredia, 31 Avenue Honorio Delgado 430, Distrito de Lima, Peru
| | - Sebastian Funk
- Centre for the Mathematical Modelling of Infectious Diseases, Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Robert H Gilman
- Laboratorio de Bioinformática y Biología Molecular, Facultad de Ciencias, Universidad Peruana Cayetano Heredia, 31 Avenue Honorio Delgado 430, Distrito de Lima, Peru.,Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe Street, Baltimore, MD 21205, USA
| | - Jon S Friedland
- Infectious Diseases and Immunity, Imperial College London, Commonwealth Building, Hammersmith Campus, Du Cane Road, London W12 0NN, UK.,Wellcome Trust Imperial College Centre for Global Health, St Mary's Hospital Campus, Imperial College London, Praed Street, London, W2 1NY, UK
| | - Louis Grandjean
- TB Centre, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.,Laboratorio de Bioinformática y Biología Molecular, Facultad de Ciencias, Universidad Peruana Cayetano Heredia, 31 Avenue Honorio Delgado 430, Distrito de Lima, Peru.,Wellcome Trust Imperial College Centre for Global Health, St Mary's Hospital Campus, Imperial College London, Praed Street, London, W2 1NY, UK
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9
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Martinez L, Zhu L, Castellanos ME, Liu Q, Chen C, Hallowell BD, Whalen CC. Glycemic Control and the Prevalence of Tuberculosis Infection: A Population-based Observational Study. Clin Infect Dis 2018; 65:2060-2068. [PMID: 29059298 DOI: 10.1093/cid/cix632] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 09/28/2017] [Indexed: 01/03/2023] Open
Abstract
Background Several cohort studies demonstrate that diabetics are at increased risk for active tuberculosis, and poor glycemic control may exacerbate this risk. A higher prevalence of tuberculosis infection at baseline among diabetics may partially explain these results; however, no population-based studies have investigated this association. Furthermore, whether glycemic control modifies the relationship between diabetes and tuberculosis infection, as it does with active tuberculosis, is unknown. Methods Diabetics were diagnosed through physician evaluation and using 3 laboratory tests including hemoglobin A1C (HbA1C), fasting plasma glucose (FPG), or 2-hour plasma glucose (PG). Tuberculosis infection was diagnosed through tuberculin skin tests, and glycemic control was assessed linearly and categorically using recommended targets. Results Among 4215 participants, the prevalence of tuberculosis infection was 4.1%, 5.5%, and 7.6% in nondiabetic, prediabetic, and diabetic participants (Ptrend = .012). In multivariate analysis, diabetes was associated with tuberculosis infection (adjusted odds ratio [AOR], 1.5; 95% confidence interval [CI], 1.0-2.2). Compared to nondiabetics, diabetics who were undiagnosed (AOR, 2.2 and 1.2 in diagnosed diabetics), FPG >130 mg/dL (AOR, 2.6 and 1.3 in diabetics with FPG ≤130 mg/dL), or not on insulin (AOR, 1.7 and 0.8 in diabetics on insulin) had elevated tuberculosis infection rates. In a linear dose-response analysis, increasing values of FPG (AOR, 1.02 per 1-mg/dL; 95% CI, 1.01-1.03), PG (AOR, 1.02 per 1-mg/dL; 95% CI, 1.01-1.04), and HbA1C (AOR, 1.13 per 1%; 95% CI, 1.04-1.22) all predicted tuberculosis infection. Conclusions Our results suggest glycemic control may modify the relationship between tuberculosis infection and diabetes.
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Affiliation(s)
- Leonardo Martinez
- Department of Epidemiology and Biostatistics.,Center for Global Health, College of Public Health, University of Georgia, Athens
| | - Limei Zhu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, People's Republic of China
| | - Maria E Castellanos
- Department of Epidemiology and Biostatistics.,Center for Global Health, College of Public Health, University of Georgia, Athens
| | - Qiao Liu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, People's Republic of China
| | - Cheng Chen
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, People's Republic of China.,Key Laboratory of Public Health Safety, Ministry of Education.,School of Public Health, Fudan University, Shanghai, China
| | - Benjamin D Hallowell
- Department of Epidemiology and Biostatistics.,Center for Global Health, College of Public Health, University of Georgia, Athens
| | - Christopher C Whalen
- Department of Epidemiology and Biostatistics.,Center for Global Health, College of Public Health, University of Georgia, Athens
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10
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Teklu T, Legesse M, Medhin G, Zewude A, Chanyalew M, Zewdie M, Wondale B, Haile-Mariam M, Pieper R, Ameni G. Latent tuberculosis infection and associated risk indicators in pastoral communities in southern Ethiopia: a community based cross-sectional study. BMC Public Health 2018; 18:266. [PMID: 29454325 PMCID: PMC5816385 DOI: 10.1186/s12889-018-5149-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 02/02/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Research pertaining to the community-based prevalence of latent tuberculosis infection (LTBI) is important to understand the magnitude of this infection. This study was conducted to estimate LTBI prevalence and to identify associated risk factors in the Omo Zone of Southern Ethiopia. METHODS A community-based cross-sectional study was conducted in six South Omo districts from May 2015 to February 2016. The sample size was allocated to the study districts proportional to their population sizes. Participants were selected using a multi-stage sampling approach. A total of 497 adult pastoralists were recruited. Blood samples were collected from the study participants and screened for LTBI using a U.S. Food and Drug Administration approved interferon-gamma release assay (IGRA). Logistic regression was used to model the likelihood of LTBI occurrence and to identify risk factors associated with LTBI. RESULTS The prevalence of LTBI was 50.5% (95% CI: 46%, 55%) with no significant gender difference (49.8% among males versus 51.2% among females; Chi-square (χ2) = 0.10; P = 0.41) and marginally non-significant increasing trends with age (44.6% among those below 24 years and 59.7% in the age range of 45-64 years; χ2 = 6.91; P = 0.075). Being residence of the Dasanech District (adjusted odds ratio, AOR = 2.62, 95% CI: 1.30, 5.28; P = 0.007) and having a habit of eating raw meat (AOR = 2.89, 95% CI: 1.09, 7.66; P = 0.033) were significantly associated with an increased odds of being positive for LTBI. A large family size (size of 5 to 10) has significant protective effect against associated a reduced odds of being positive for LTBI compared to a family size of below 5 (AOR = 0.65, 95% CI: 0.42, 0.99; P = 0.045). CONCLUSIONS A high prevalence of LTBI in the South Omo Zone raises the concern that elimination of TB in the pastoral communities of the region might be difficult. Screening for and testing individuals infected with TB, independent of symptoms, may be an effective way to minimize the risk of disease spread.
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Affiliation(s)
- Takele Teklu
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
- Department of Immunology and Molecular Biology, College on Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Mengistu Legesse
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
| | - Girmay Medhin
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
| | - Aboma Zewude
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
| | - Mahlet Chanyalew
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
| | - Martha Zewdie
- Armauer Hansen Research Institute, AHRI, PO Box 1005, Addis Ababa, Ethiopia
| | - Biniam Wondale
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
- Department of Biology, College of Natural Sciences, Arbaminch University, Arbaminch, Ethiopia
| | - Milkessa Haile-Mariam
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
- Department of Veterinary Laboratory, College of Agriculture, Ambo University, Guder, Ethiopia
| | | | - Gobena Ameni
- Aklilu Lemma Institute of Pathobiology (ALIPB), Addis Ababa University, P O Box 1176, Addis Ababa, Ethiopia
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11
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Lu P, Ding X, Liu Q, Lu W, Martinez L, Sun J, Lu F, Zhong C, Jiang H, Miao C, Zhu L, Yang H. Mediating Effect of Repeated Tuberculosis Exposure on the Risk of Transmission to Household Contacts of Multidrug-Resistant Tuberculosis Patients. Am J Trop Med Hyg 2017; 98:364-371. [PMID: 29210348 PMCID: PMC5929184 DOI: 10.4269/ajtmh.17-0325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Primary Mycobacterium tuberculosis transmission is an important driver of the global epidemic of resistance to tuberculosis drugs. A few studies have compared tuberculosis infection in contacts of index cases with different drug-resistant profiles, suggesting that contacts of multidrug-resistant (MDR) tuberculosis cases are at higher risk. Repeated tuberculosis exposure in contacts of MDR tuberculosis patients through recurrent tuberculosis may modify this relationship. We compared tuberculosis infection in household contacts of MDR and drug-susceptible (DS) tuberculosis patients from six cities in southeastern China and investigated whether repeated tuberculosis exposure was a mediating factor. Tuberculosis infection was defined as a tuberculin skin test induration ≥ 10 mm. In all, 111 (28.0%) of 397 household contacts of MDR tuberculosis patients and 165 (24.7%) of 667 contacts of DS tuberculosis index cases were infected with tuberculosis. In a multivariate model not including the previous tuberculosis exposure, contacts of MDR tuberculosis patients had a higher likelihood of tuberculosis infection (adjusted odds ratio [AOR] = 1.37; 95% confidence interval [CI] = 1.01-1.84; P = 0.041). In a separate multivariate model adjusted for the previous tuberculosis exposure, the odds ratio of tuberculosis infection flipped and contacts of MDR cases were now at lower risk for tuberculosis infection (AOR = 0.55; 95% CI = 0.38-0.81; P = 0.003). These findings suggest prior tuberculosis exposure in contacts strongly mediates the relationship between tuberculosis infection and the index drug resistance profile. Prior studies showing lower risk of developing tuberculosis among contacts of MDR tuberculosis patients may be partially explained by a lower rate of tuberculosis infection at baseline.
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Affiliation(s)
- Peng Lu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Xiaoyan Ding
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Qiao Liu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Wei Lu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Leonardo Martinez
- School of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California.,Department of Epidemiology and Biostatistics, University of Georgia School of Public Health, Athens, Georgia
| | - Jiansheng Sun
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Xuzhou City, Jiangsu Province, China
| | - Feng Lu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Nantong City, Jiangsu Province, China
| | - Chongqiao Zhong
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Lianyungang City, Jiangsu Province, China
| | - Hui Jiang
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Zhenjiang City, Jiangsu Province, China
| | - Changdong Miao
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Taizhou City, Jiangsu Province, China
| | - Limei Zhu
- Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
| | - Haitao Yang
- Jiangsu Institute of Parasitic Diseases, Jiangsu Province, China.,Department of Chronic Communicable Disease, Center for Disease Control and Prevention of Jiangsu Province, Nanjing, Jiangsu Province, People's Republic of China
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12
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Datta S, Sherman JM, Tovar MA, Bravard MA, Valencia T, Montoya R, Quino W, D'Arcy N, Ramos ES, Gilman RH, Evans CA. Sputum Microscopy With Fluorescein Diacetate Predicts Tuberculosis Infectiousness. J Infect Dis 2017; 216:514-524. [PMID: 28510693 PMCID: PMC5853787 DOI: 10.1093/infdis/jix229] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 05/11/2017] [Indexed: 01/03/2023] Open
Abstract
Background Sputum from patients with tuberculosis contains subpopulations of metabolically active and inactive Mycobacterium tuberculosis with unknown implications for infectiousness. Methods We assessed sputum microscopy with fluorescein diacetate (FDA, evaluating M. tuberculosis metabolic activity) for predicting infectiousness. Mycobacterium tuberculosis was quantified in pretreatment sputum of patients with pulmonary tuberculosis using FDA microscopy, culture, and acid-fast microscopy. These 35 patients’ 209 household contacts were followed with prevalence surveys for tuberculosis disease for 6 years. Results FDA microscopy was positive for a median of 119 (interquartile range [IQR], 47–386) bacteria/µL sputum, which was 5.1% (IQR, 2.4%–11%) the concentration of acid-fast microscopy–positive bacteria (2069 [IQR, 1358–3734] bacteria/μL). Tuberculosis was diagnosed during follow-up in 6.4% (13/209) of contacts. For patients with lower than median concentration of FDA microscopy–positive M. tuberculosis, 10% of their contacts developed tuberculosis. This was significantly more than 2.7% of the contacts of patients with higher than median FDA microscopy results (crude hazard ratio [HR], 3.8; P = .03). This association maintained statistical significance after adjusting for disease severity, chemoprophylaxis, drug resistance, and social determinants (adjusted HR, 3.9; P = .02). Conclusions Mycobacterium tuberculosis that was FDA microscopy negative was paradoxically associated with greater infectiousness. FDA microscopy–negative bacteria in these pretreatment samples may be a nonstaining, slowly metabolizing phenotype better adapted to airborne transmission.
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Affiliation(s)
- Sumona Datta
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Infectious Diseases and Immunity and Wellcome Trust Centre for Global Health Research, Imperial College London, United Kingdom.,Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
| | - Jonathan M Sherman
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Marco A Tovar
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
| | - Marjory A Bravard
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Teresa Valencia
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Rosario Montoya
- Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
| | - Willi Quino
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
| | - Nikki D'Arcy
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
| | - Eric S Ramos
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Robert H Gilman
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Carlton A Evans
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Peru.,Infectious Diseases and Immunity and Wellcome Trust Centre for Global Health Research, Imperial College London, United Kingdom.,Innovacion por la Salud y el Desarollo (IPSYD), Asociación Benéfica Prisma, Lima, Peru
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13
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Bonadonna LV, Saunders MJ, Zegarra R, Evans C, Alegria-Flores K, Guio H. Why wait? The social determinants underlying tuberculosis diagnostic delay. PLoS One 2017; 12:e0185018. [PMID: 28945782 PMCID: PMC5612650 DOI: 10.1371/journal.pone.0185018] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 09/04/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Early detection and diagnosis of tuberculosis remain major global priorities for tuberculosis control. Few studies have used a qualitative approach to investigate the social determinants contributing to diagnostic delay and none have compared data collected from individual, community, and health-system levels. We aimed to characterize the social determinants that contribute to diagnostic delay among persons diagnosed with tuberculosis living in resource-constrained settings. METHODS/PRINCIPLE FINDINGS Data were collected in public health facilities with high tuberculosis incidence in 19 districts of Lima, Peru. Semi-structured interviews with persons diagnosed with tuberculosis (n = 105) and their family members (n = 63) explored health-seeking behaviours, community perceptions of tuberculosis and socio-demographic circumstances. Focus groups (n = 6) were conducted with health personnel (n = 35) working in the National Tuberculosis Program. All interview data were transcribed and analysed using a grounded theory approach. The median delay between symptom onset and the public health facility visit that led to the first positive diagnostic sample was 57 days (interquartile range 28-126). The great majority of persons diagnosed with tuberculosis distrusted the public health system and sought care at public health facilities only after exhausting other options. It was universally agreed that persons diagnosed with tuberculosis faced discrimination by public and health personnel. Self-medication with medicines bought at local pharmacies was reported as the most common initial health-seeking behaviour due to the speed and low-cost of treatment in pharmacies. Most persons diagnosed with tuberculosis initially perceived their illness as a simple virus. CONCLUSIONS Diagnostic delay was common and prolonged. When individuals reached a threshold of symptom severity, they addressed their health with the least time-consuming, most economically feasible, and well-known healthcare option available to them. In high-burden settings, more human and material resources are required to promote tuberculosis case-finding initiatives, reduce tuberculosis associated stigma and address the social determinants underlying diagnostic delay.
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Affiliation(s)
- Lily Victoria Bonadonna
- The University of Michigan, Ann Arbor, Michigan, United States of America
- Instituto Nacional de Salud, Lima, Perú
- Innovación Por la Salud Y Desarrollo (IPSYD), Asociación Benéfica PRISMA, Lima, Perú
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Perú
- * E-mail:
| | - Matthew James Saunders
- Innovación Por la Salud Y Desarrollo (IPSYD), Asociación Benéfica PRISMA, Lima, Perú
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Perú
- Infectious Diseases & Immunity, Imperial College London, and Wellcome Trust Imperial College Centre for Global Health Research, London, United Kingdom
| | | | - Carlton Evans
- Innovación Por la Salud Y Desarrollo (IPSYD), Asociación Benéfica PRISMA, Lima, Perú
- Innovation for Health and Development (IFHAD), Laboratory of Research and Development, Universidad Peruana Cayetano Heredia, Lima, Perú
- Infectious Diseases & Immunity, Imperial College London, and Wellcome Trust Imperial College Centre for Global Health Research, London, United Kingdom
| | - Kei Alegria-Flores
- Department of Health Policy and Management, University of North Carolina Gillings School of Global Public Health, Chapel Hill, North Carolina, United States of America
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14
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Solari L, Soto A, Van der Stuyft P. Performance of clinical prediction rules for diagnosis of pleural tuberculosis in a high-incidence setting. Trop Med Int Health 2017; 22:1283-1292. [PMID: 28727272 DOI: 10.1111/tmi.12932] [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] [Indexed: 01/18/2023]
Abstract
OBJECTIVES Diagnosis of pleural tuberculosis (PT) is still a challenge, particularly in resource-constrained settings. Alternative diagnostic tools are needed. We aimed at evaluating the utility of Clinical Prediction Rules (CPRs) for diagnosis of pleural tuberculosis in Peru. METHODS We identified CPRs for diagnosis of PT through a structured literature search. CPRs using high-complexity tests, as defined by the FDA, were excluded. We applied the identified CPRs to patients with pleural exudates attending two third-level hospitals in Lima, Peru, a setting with high incidence of tuberculosis. Besides pleural fluid analysis, patients underwent closed pleural biopsy for reaching a final diagnosis through combining microbiological and histopathological criteria. We evaluated the performance of the CPRs against this composite reference standard using classic indicators of diagnostic test validity. RESULTS We found 15 eligible CPRs, of which 12 could be validated. Most included ADA, age, lymphocyte proportion and protein in pleural fluid as predictive findings. A total of 259 patients were included for their validation, of which 176 (67%) had PT and 50 (19%) malignant pleural effusion. The overall accuracy of the CPRs varied from 41% to 86%. Two had a positive likelihood ratio (LR) above 10, but none a negative LR below 0.1. ADA alone at a cut-off of ≥40 IU attained 87% diagnostic accuracy and had a positive LR of 6.6 and a negative LR of 0.2. CONCLUSION Many CPRs for PT are available. In addition to ADA alone, none of them contributes significantly to diagnosis of PT.
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Affiliation(s)
- Lely Solari
- Unit of General Epidemiology and Disease Control, Institute of Tropical Medicine of Antwerp, Antwerp, Belgium.,Escuela de Medicina, Universidad Peruana de Ciencias Aplicadas, Lima, Peru
| | - Alonso Soto
- Escuela de Medicina, Universidad Peruana de Ciencias Aplicadas, Lima, Peru
| | - Patrick Van der Stuyft
- Unit of General Epidemiology and Disease Control, Institute of Tropical Medicine of Antwerp, Antwerp, Belgium.,Department of Public Health, Ghent University, Ghent, Belgium
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15
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Ncayiyana JR, Bassett J, West N, Westreich D, Musenge E, Emch M, Pettifor A, Hanrahan CF, Schwartz SR, Sanne I, van Rie A. Prevalence of latent tuberculosis infection and predictive factors in an urban informal settlement in Johannesburg, South Africa: a cross-sectional study. BMC Infect Dis 2016; 16:661. [PMID: 27825307 PMCID: PMC5101651 DOI: 10.1186/s12879-016-1989-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 10/28/2016] [Indexed: 01/18/2023] Open
Abstract
Background South Africa has one of the highest burdens of latent tuberculosis infection (LTBI) in high-risk populations such as young children, adolescents, household contacts of TB cases, people living with HIV, gold miners and health care workers, but little is known about the burden of LTBI in its general population. Methods Using a community-based survey with random sampling, we examined the burden of LTBI in an urban township of Johannesburg and investigated factors associated with LTBI. The outcome of LTBI was based on TST positivity, with a TST considered positive if the induration was ≥5 mm in people living with HIV or ≥10 mm in those with unknown or HIV negative status. We used bivariate and multivariable logistic regression to identify factors associated with LTBI Results The overall prevalence of LTBI was 34.3 (95 % CI 30.0, 38.8 %), the annual risk of infection among children age 0–14 years was 3.1 % (95 % CI 2.1, 5.2). LTBI was not associated with HIV status. In multivariable logistic regression analysis, LTBI was associated with age (OR = 1.03 for every year increase in age, 95 % CI = 1.01–1.05), male gender (OR = 2.70, 95 % CI = 1.55–4.70), marital status (OR = 2.00, 95 % CI = 1.31–3.54), and higher socio-economic status (OR = 2.11, 95 % CI = 1.04–4.31). Conclusions The prevalence of LTBI and the annual risk of infection with M. tuberculosis is high in urban populations, especially in men, but independent of HIV infection status. This study suggests that LTBI may be associated with higher SES, in contrast to the well-established association between TB disease and poverty.
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Affiliation(s)
- Jabulani R Ncayiyana
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA. .,Division of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 29 Princess of Wales Terrace, Johannesburg, 2193, South Africa.
| | - Jean Bassett
- Witkoppen Health and Welfare Centre, 105 William Nicol Drive, Fourways, Johannesburg, 2055, South Africa
| | - Nora West
- Witkoppen Health and Welfare Centre, 105 William Nicol Drive, Fourways, Johannesburg, 2055, South Africa
| | - Daniel Westreich
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Eustasius Musenge
- Division of Epidemiology and Biostatistics, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 29 Princess of Wales Terrace, Johannesburg, 2193, South Africa
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Audrey Pettifor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Colleen F Hanrahan
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD, 21205, USA
| | - Sheree R Schwartz
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe Street, Baltimore, MD, 21205, USA
| | - Ian Sanne
- Clinical HIV Research Unit, Department of Medicine, University of the Witwatersrand, Perth Road, Auckland Park, Johannesburg, 2092, South Africa
| | - Annelies van Rie
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.,Department of Epidemiology and Social Medicine, Faculty of Medicine and Health Sciences, University of Antwerp, Campus Drie Eiken, University Square, Wilrijk, Antwerp, 2610, Belgium
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16
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Martinez L, Sekandi JN, Castellanos ME, Zalwango S, Whalen CC. Infectiousness of HIV-Seropositive Patients with Tuberculosis in a High-Burden African Setting. Am J Respir Crit Care Med 2016; 194:1152-1163. [PMID: 27181053 PMCID: PMC5114446 DOI: 10.1164/rccm.201511-2146oc] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 04/28/2016] [Indexed: 12/11/2022] Open
Abstract
RATIONALE Policy recommendations on contact investigation of HIV-seropositive patients with tuberculosis have changed several times. Current epidemiologic evidence informing these recommendations is considered low quality, and few large studies investigating the infectiousness of HIV-seropositive and -seronegative index cases have been performed in sub-Saharan Africa. OBJECTIVES We assessed the infectiousness of HIV-seropositive and -seronegative patients with tuberculosis to their household contacts and examined potential modifiers of this relationship. METHODS Adults suffering from their first episode of pulmonary tuberculosis were identified in Kampala, Uganda. Field workers visited index households and enrolled consenting household contacts. Latent tuberculosis infection was measured through tuberculin skin testing, and relative risks were calculated using modified Poisson regression models. Standard assessments of interaction between latent tuberculosis infection, the HIV serostatus of index cases, and other variables were performed. MEASUREMENTS AND MAIN RESULTS Latent tuberculosis infection was found in 577 of 878 (65.7%) and 717 of 974 (73.6%) household contacts of HIV-seropositive and -seronegative tuberculosis cases (relative risk, 0.89; 95% confidence interval, 0.82-0.97). On further stratification, cavitary lung disease (P < 0.0001 for interaction) and smear status (P = 0.02 for interaction) of tuberculosis cases modified the infectiousness of HIV-seropositive indexes. Cough duration of index cases did not display interaction (P = 0.499 for interaction). CONCLUSIONS This study suggests that HIV-seropositive tuberculosis cases may be less infectious than HIV-seronegative patients only when they are smear-negative or lack cavitary lung disease. These results may explain heterogeneity between prior studies and provide evidence suggesting that tuberculosis contact investigation should include HIV-seropositive index cases in high disease burden settings.
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Affiliation(s)
- Leonardo Martinez
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia
| | - Juliet N. Sekandi
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia
- School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda; and
| | - María E. Castellanos
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia
| | - Sarah Zalwango
- Uganda–CWRU Research Collaboration, Makerere University and Mulago Hospital, Kampala, Uganda
| | - Christopher C. Whalen
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, Georgia
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17
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Westerlund EE, Tovar MA, Lönnermark E, Montoya R, Evans CA. Tuberculosis-related knowledge is associated with patient outcomes in shantytown residents; results from a cohort study, Peru. J Infect 2015; 71:347-57. [PMID: 26033695 DOI: 10.1016/j.jinf.2015.05.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/19/2015] [Accepted: 05/26/2015] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Tuberculosis is frequent among poor and marginalized people whose limited tuberculosis-related knowledge may impair healthcare access. We characterised tuberculosis-related knowledge and associations with delayed treatment and treatment outcome. METHODS Tuberculosis patients (n = 943), people being tested for suspected tuberculosis (n = 2020), and randomly selected healthy controls (n = 476) in 16 periurban shantytowns were interviewed characterizing: socio-demographic factors; tuberculosis risk-factors; and patients' treatment delay. Principle component analysis was used to generate a tuberculosis-related knowledge score. Patients were followed-up for median 7.7 years. Factors associated with tuberculosis treatment delay, treatment outcome and tuberculosis recurrence were assessed using linear, logistic and Cox regression. RESULTS Tuberculosis-related knowledge was poor, especially in older people who had not completed schooling and had never been diagnosed with tuberculosis. Tuberculosis treatment delay was median 60 days and was more delayed for patients who were poorer, older, had more severe tuberculosis and in only unadjusted analysis with incomplete schooling and low tuberculosis-related knowledge (all p ≤ 0.03). Lower than median tuberculosis-related knowledge was associated with tuberculosis recurrence (unadjusted hazard ratio = 2.1, p = 0.008), and this association was independent of co-morbidities, disease severity and demographic factors (multiple regression adjusted hazard ratio = 2.6, p = 0.008). CONCLUSIONS Low tuberculosis-related knowledge independently predicted tuberculosis recurrence. Thus health education may improve tuberculosis prognosis.
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Affiliation(s)
- Emma E Westerlund
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development #218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru; Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Marco A Tovar
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development #218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru; Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Elisabet Lönnermark
- Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Rosario Montoya
- Innovacion Por la Salud Y el Desarollo (IPSYD), Asociación Benefica Prisma, Lima, Peru
| | - Carlton A Evans
- IFHAD: Innovation For Health And Development, Laboratory of Research and Development #218, Universidad Peruana Cayetano Heredia, San Martin de Porres, Lima, Peru; Infectious Diseases & Immunity, Imperial College London, and Wellcome Trust Imperial College Centre for Global Health Research, London, UK.
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18
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Shu CC, Hsu CL, Lee CY, Wang JY, Wu VC, Yang FJ, Wang JT, Yu CJ, Lee LN. Comparison of the Prevalence of Latent Tuberculosis Infection among Non-Dialysis Patients with Severe Chronic Kidney Disease, Patients Receiving Dialysis, and the Dialysis-Unit Staff: A Cross-Sectional Study. PLoS One 2015; 10:e0124104. [PMID: 25919813 PMCID: PMC4412816 DOI: 10.1371/journal.pone.0124104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 02/25/2015] [Indexed: 01/15/2023] Open
Abstract
Background Patients with renal failure are vulnerable to tuberculosis, a common worldwide infectious disease. In the growing dialysis population, the risk for tuberculosis among the associated sub-groups is important but unclear. This study investigated latent tuberculosis infection (LTBI) in patients with severe chronic kidney disease (CKD) and among dialysis-unit staff caring for patients on dialysis. Methods From January 2012 to June 2013, patients undergoing dialysis, those with severe CKD (estimated glomerular filtration rate <30ml/min/1.73 m2), and the dialysis-unit staff (nursing staff and doctors in hemodialysis units) in several Taiwan hospitals were prospectively enrolled. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-tube was used to determine LTBI. Predictors for LTBI were analyzed. Results Of the 599 participants enrolled, 106 (25%) in the dialysis group were IGRA positive. This was higher than the seven (11%) among severe CKD patients and 12 (11%) in the dialysis-unit staff. Independent predictors of LTBI in patient with renal dysfunction were old age (odds ratio [OR]: 1.03 [1.01–1.04] per year increment), prior TB lesion on chest radiograph (OR: 2.90 [1.45–5.83]), serum albumin (OR: 2.59 [1.63–4.11] per 1 g/dl increment), and need for dialysis (OR: 2.47, [1.02–5.95]). The QFT-GIT response was similar among the three groups. Malignancy (OR: 4.91 [1.84–13.10]) and low serum albumin level (OR: 0.22 [0.10–0.51], per 1 g/dl decrease) were associated with indeterminate IGRA results. Conclusions More patients on dialysis have LTBI compared to those with severe CKD and the dialysis-unit staff. Old age, prior radiographic TB lesion, high serum albumin, and need for dialysis are predictors of LTBI in patients with renal failure. Patients with severe CKD are a lower priority for LTBI screening. The hemodialysis environment is not a risk for LTBI and dialysis-unit staff may be treated as general healthcare workers.
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Affiliation(s)
- Chin-Chung Shu
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei City, Taiwan
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Traumatology, National Taiwan University Hospital, Taipei City, Taiwan
- * E-mail:
| | - Chia-Lin Hsu
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Chih-Yuan Lee
- Department of Surgery, National Taiwan University Hospital, Taipei City, Taiwan
| | - Jann-Yuan Wang
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Vin-Cent Wu
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Feng-Jung Yang
- Department of Internal Medicine, National Taiwan University Hospital, Yun-Lin Branch, Yun-Lin County, Taiwan
| | - Jann-Tay Wang
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Chong-Jen Yu
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
| | - Li-Na Lee
- School of Medicine, National Taiwan University, Taipei City, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei City, Taiwan
- Department of Laboratory Medicine, National Taiwan University Hospital, Taipei City, Taiwan
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19
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Kizza FN, List J, Nkwata AK, Okwera A, Ezeamama AE, Whalen CC, Sekandi JN. Prevalence of latent tuberculosis infection and associated risk factors in an urban African setting. BMC Infect Dis 2015; 15:165. [PMID: 25879423 PMCID: PMC4392742 DOI: 10.1186/s12879-015-0904-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 03/13/2015] [Indexed: 11/10/2022] Open
Abstract
Background Nearly one third of the world is infected with latent tuberculosis infection (LTBI) and a vast pool of individuals with LTBI persists in developing countries, posing a major barrier to global TB control. The aim of the present study was to determine the prevalence of LTBI and the associated risk factors among adults in Kampala, Uganda. Methods We performed a secondary analysis from a door-to-door cross-sectional survey of chronic cough conducted from January 2008 to June 2009. Urban residents of Rubaga community in Kampala aged 15 years and older who had received Tuberculin skin testing (TST) were included in the analysis. The primary outcome was LTBI defined as a TST with induration 10 mm or greater. Multivariable logistic regression analyses were used to assess the risk factors associated with LTBI. Results A total of 290 participants were tested with TST, 283 had their tests read and 7 didn’t have the TST read because of failure to trace them within 48–72 hours. Of the participants with TST results, 68% were female, 75% were 15–34 years, 83% had attained at least 13 years of education, 12% were smokers, 50% were currently married, 57% left home for school or employment, 21% were HIV positive and 65% reported chronic cough of 2 weeks or longer. The overall prevalence of LTBI was 49% [95% CI 44–55] with some age-and sex-specific differences. On multivariable analysis, leaving home for school or employment, aOR = 1.72; [95%CI: 1.05, 2.81] and age 25–34, aOR = 1.94; [95%CI: 1.12, 3.38]; 35 years and older, aOR = 3.12; [95%CI: 1.65, 5.88] were significant risk factors of LTBI. Conclusion The prevalence of LTBI was high in this urban African setting. Leaving home for school or employment and older age were factors significantly associated with LTBI in this setting. This suggests a potential role of expansion of one’s social network outside the home and cumulative risk of exposure to TB with age in the acquisition of LTBI. Our results provide support for LTBI screening and preventive treatment programs of these sub-groups in order to enhance TB control.
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Affiliation(s)
- Florence N Kizza
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
| | - Justin List
- Department of Internal Medicine University of Michigan, Ann Arbor, MI, USA.
| | - Allan K Nkwata
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
| | - Alphonse Okwera
- National TB Treatment Center, School of Medicine, Makerere University, Mulago, Uganda.
| | - Amara E Ezeamama
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
| | - Christopher C Whalen
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA.
| | - Juliet N Sekandi
- Department of Epidemiology and Biostatistics, College of Public Health, University of Georgia, Athens, GA, USA. .,Makerere University School of Public Health, Kampala, Uganda.
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20
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Wingfield T, Schumacher SG, Sandhu G, Tovar MA, Zevallos K, Baldwin MR, Montoya R, Ramos ES, Jongkaewwattana C, Lewis JJ, Gilman RH, Friedland JS, Evans CA. The seasonality of tuberculosis, sunlight, vitamin D, and household crowding. J Infect Dis 2014; 210:774-83. [PMID: 24596279 PMCID: PMC4130318 DOI: 10.1093/infdis/jiu121] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background. Unlike other respiratory infections, tuberculosis diagnoses increase in summer. We performed an ecological analysis of this paradoxical seasonality in a Peruvian shantytown over 4 years. Methods. Tuberculosis symptom-onset and diagnosis dates were recorded for 852 patients. Their tuberculosis-exposed cohabitants were tested for tuberculosis infection with the tuberculin skin test (n = 1389) and QuantiFERON assay (n = 576) and vitamin D concentrations (n = 195) quantified from randomly selected cohabitants. Crowding was calculated for all tuberculosis-affected households and daily sunlight records obtained. Results. Fifty-seven percent of vitamin D measurements revealed deficiency (<50 nmol/L). Risk of deficiency was increased 2.0-fold by female sex (P < .001) and 1.4-fold by winter (P < .05). During the weeks following peak crowding and trough sunlight, there was a midwinter peak in vitamin D deficiency (P < .02). Peak vitamin D deficiency was followed 6 weeks later by a late-winter peak in tuberculin skin test positivity and 12 weeks after that by an early-summer peak in QuantiFERON positivity (both P < .04). Twelve weeks after peak QuantiFERON positivity, there was a midsummer peak in tuberculosis symptom onset (P < .05) followed after 3 weeks by a late-summer peak in tuberculosis diagnoses (P < .001). Conclusions. The intervals from midwinter peak crowding and trough sunlight to sequential peaks in vitamin D deficiency, tuberculosis infection, symptom onset, and diagnosis may explain the enigmatic late-summer peak in tuberculosis.
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Affiliation(s)
- Tom Wingfield
- IFHAD: Innovation For Health and Development, United Kingdom Infectious Diseases and Immunity, Imperial College London Wellcome Trust Imperial College Centre for Global Health Research, London The Monsall Infectious Diseases Unit, North Manchester General Hospital, Manchester
| | - Samuel G Schumacher
- IFHAD: Innovation For Health and Development, United Kingdom Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú
| | - Gurjinder Sandhu
- Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú Infectious Diseases and Immunity, Imperial College London Wellcome Trust Imperial College Centre for Global Health Research, London
| | - Marco A Tovar
- IFHAD: Innovation For Health and Development, United Kingdom Asociación Benefica Prisma Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú
| | - Karine Zevallos
- IFHAD: Innovation For Health and Development, United Kingdom Asociación Benefica Prisma
| | - Matthew R Baldwin
- Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú
| | - Rosario Montoya
- IFHAD: Innovation For Health and Development, United Kingdom Asociación Benefica Prisma
| | - Eric S Ramos
- Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú
| | | | - James J Lewis
- IFHAD: Innovation For Health and Development, United Kingdom Medical Research Council Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robert H Gilman
- Asociación Benefica Prisma School of Public Health, Johns Hopkins Bloomberg School of Hygiene and Public Health, Baltimore, Maryland
| | - Jon S Friedland
- Infectious Diseases and Immunity, Imperial College London Wellcome Trust Imperial College Centre for Global Health Research, London
| | - Carlton A Evans
- IFHAD: Innovation For Health and Development, United Kingdom Laboratorio de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Perú Infectious Diseases and Immunity, Imperial College London Wellcome Trust Imperial College Centre for Global Health Research, London
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