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Vasconcelos A, King JD, Nunes-Alves C, Anderson R, Argaw D, Basáñez MG, Bilal S, Blok DJ, Blumberg S, Borlase A, Brady OJ, Browning R, Chitnis N, Coffeng LE, Crowley EH, Cucunubá ZM, Cummings DAT, Davis CN, Davis EL, Dixon M, Dobson A, Dyson L, French M, Fronterre C, Giorgi E, Huang CI, Jain S, James A, Kim SH, Kura K, Lucianez A, Marks M, Mbabazi PS, Medley GF, Michael E, Montresor A, Mutono N, Mwangi TS, Rock KS, Saboyá-Díaz MI, Sasanami M, Schwehm M, Spencer SEF, Srivathsan A, Stawski RS, Stolk WA, Sutherland SA, Tchuenté LAT, de Vlas SJ, Walker M, Brooker SJ, Hollingsworth TD, Solomon AW, Fall IS. Accelerating Progress Towards the 2030 Neglected Tropical Diseases Targets: How Can Quantitative Modeling Support Programmatic Decisions? Clin Infect Dis 2024; 78:S83-S92. [PMID: 38662692 PMCID: PMC11045030 DOI: 10.1093/cid/ciae082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2024] Open
Abstract
Over the past decade, considerable progress has been made in the control, elimination, and eradication of neglected tropical diseases (NTDs). Despite these advances, most NTD programs have recently experienced important setbacks; for example, NTD interventions were some of the most frequently and severely impacted by service disruptions due to the coronavirus disease 2019 (COVID-19) pandemic. Mathematical modeling can help inform selection of interventions to meet the targets set out in the NTD road map 2021-2030, and such studies should prioritize questions that are relevant for decision-makers, especially those designing, implementing, and evaluating national and subnational programs. In September 2022, the World Health Organization hosted a stakeholder meeting to identify such priority modeling questions across a range of NTDs and to consider how modeling could inform local decision making. Here, we summarize the outputs of the meeting, highlight common themes in the questions being asked, and discuss how quantitative modeling can support programmatic decisions that may accelerate progress towards the 2030 targets.
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Affiliation(s)
- Andreia Vasconcelos
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
- Centre for Global Health Research, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
| | - Jonathan D King
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Cláudio Nunes-Alves
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
| | - Roy Anderson
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Daniel Argaw
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Maria-Gloria Basáñez
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Shakir Bilal
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - David J Blok
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Seth Blumberg
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Anna Borlase
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | - Oliver J Brady
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Raiha Browning
- The Department of Statistics, The University of Warwick, Coventry, United Kingdom
| | - Nakul Chitnis
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Luc E Coffeng
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Emily H Crowley
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Zulma M Cucunubá
- Departamento de Epidemiología Clínica y Bioestadística, Facultad de Medicina, Universidad Pontificia Javeriana, Bogotá, Colombia
| | - Derek A T Cummings
- Department of Biology, University of Florida, Gainesville, Florida, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
| | - Christopher Neil Davis
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Emma Louise Davis
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Matthew Dixon
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Andrew Dobson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA
| | - Louise Dyson
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Michael French
- Schistosomiasis Control Initiative, Department of Infectious Disease Epidemiology, St Mary's Campus, Imperial College London, London, United Kingdom
- RTI International, Washington, D.C., USA
| | - Claudio Fronterre
- CHICAS, Lancaster Medical School, Lancaster University, Lancaster, United Kingdom
| | - Emanuele Giorgi
- CHICAS, Lancaster Medical School, Lancaster University, Lancaster, United Kingdom
| | - Ching-I Huang
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Saurabh Jain
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Ananthu James
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sung Hye Kim
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Klodeta Kura
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, United Kingdom
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, United Kingdom
| | - Ana Lucianez
- Communicable Diseases Prevention, Control, and Elimination, Pan American Health Organization, Washington D.C., USA
| | - Michael Marks
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Pamela Sabina Mbabazi
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Graham F Medley
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Edwin Michael
- College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Antonio Montresor
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Nyamai Mutono
- Centre for Epidemiological Modelling and Analysis, University of Nairobi, Nairobi, Kenya
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington, USA
| | - Thumbi S Mwangi
- Centre for Epidemiological Modelling and Analysis, University of Nairobi, Nairobi, Kenya
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington, USA
- Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Kat S Rock
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Mathematics Institute, The University of Warwick, Coventry, United Kingdom
| | - Martha-Idalí Saboyá-Díaz
- Communicable Diseases Prevention, Control, and Elimination, Pan American Health Organization, Washington D.C., USA
| | - Misaki Sasanami
- Lancaster Medical School, Lancaster University, Lancaster, United Kingdom
| | - Markus Schwehm
- ExploSYS GmbH, Interdisciplinary Institute for Exploratory Systems, Leinfelden-Echterdingen, Germany
| | - Simon E F Spencer
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Ariktha Srivathsan
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Robert S Stawski
- Institute of Public Health and Wellbeing, School of Health and Social Care, University of Essex, Essex, United Kingdom
| | - Wilma A Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Samuel A Sutherland
- Zeeman Institute for System Biology and Infectious Disease Epidemiology Research, The University of Warwick, Coventry, United Kingdom
- Warwick Medical School, The University of Warwick, Coventry, United Kingdom
| | | | - Sake J de Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | | | - T Déirdre Hollingsworth
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Old Road Campus, Oxford, United Kingdom
| | - Anthony W Solomon
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Ibrahima Socé Fall
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
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Miecha H, Dejene M, Adugna D, Kebede A, Yadeta D, Alemayehu A, Abateneh A, Dayessa M, Shafi M, Taye E, Balcha L, Negussu N, Mengistu B, Willis R, Jimenez C, Bakhtiari A, Boyd S, Kebede B, Tadesse F, Mamo A, Bekele M, Sinke Z, Solomon AW, Harding-Esch EM. Prevalence of Trachoma in Pre-validation Surveillance Surveys in 11 Evaluation Units (Covering 12 Districts) in Oromia Regional State, Ethiopia: Results from 2018-2020. Ophthalmic Epidemiol 2023; 30:655-662. [PMID: 36519777 PMCID: PMC10581667 DOI: 10.1080/09286586.2022.2119258] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 08/06/2022] [Accepted: 08/25/2022] [Indexed: 12/23/2022]
Abstract
PURPOSE Interventions to reduce the prevalence of trachoma and transmission of ocular Chlamydia trachomatis have been implemented in Oromia Region, Ethiopia. Following an impact survey in which the trachomatous inflammation-follicular (TF) prevalence in 1-9-year-olds is <5%, a surveillance survey is recommended 2 years later, without additional antibiotic treatment. We report results of surveillance surveys in 11 evaluation units (EUs) covering 12 districts in Oromia Region, to plan whether future interventions are needed. METHOD We use a two-stage cluster-sampling cross-sectional survey design. In each EU, 26 clusters (villages) were systematically selected with probability proportional to size; from each cluster, 30 households were selected using compact segment sampling. Water, sanitation and hygiene (WASH) access was assessed in all selected households. All residents of selected households aged ≥1 year were examined for TF and trachomatous trichiasis (TT) by certified graders. RESULT Of 31,991 individuals enumerated, 29,230 (91% of) individuals were examined. Eight EUs had an age-adjusted TF prevalence in 1-9-year-olds of ≥5% and seven had a TT prevalence unknown to the health system among adults aged ≥15 years of ≥0.2%. About one-third of visited households had access to an improved water source for drinking, and 5% had access to an improved latrine. CONCLUSION Despite TF reductions to <5% at impact survey, prevalence recrudesced to ≥5% in all but three of the 11 EUs. Operational research is needed to understand transmission dynamics and epidemiology, in order to optimise elimination strategies in high-transmission settings like these.
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Affiliation(s)
- Hirpa Miecha
- Oromia Regional State Health Bureau, Addis Ababa, Ethiopia
| | | | - Dereje Adugna
- Oromia Regional State Health Bureau, Addis Ababa, Ethiopia
| | - Ageru Kebede
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | - Damtew Yadeta
- Oromia Regional State Health Bureau, Addis Ababa, Ethiopia
| | | | | | | | | | | | - Leta Balcha
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | | | | | - Rebecca Willis
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | | | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Sarah Boyd
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | | | | | - Ayele Mamo
- Oromia Regional State Health Bureau, Addis Ababa, Ethiopia
| | | | - Zelalem Sinke
- Oromia Regional State Health Bureau, Addis Ababa, Ethiopia
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Emma M. Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
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3
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Barazanji M, Ngo JD, Powe JA, Schneider KP, Rychtář J, Taylor D. Modeling the "F" in "SAFE": The dynamic game of facial cleanliness in trachoma prevention. PLoS One 2023; 18:e0287464. [PMID: 37352249 PMCID: PMC10289400 DOI: 10.1371/journal.pone.0287464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 06/06/2023] [Indexed: 06/25/2023] Open
Abstract
Trachoma, a neglected tropical disease (NTDs) caused by bacterium Chlamydia trachomatis, is a leading cause of infectious blindness. Efforts are underway to eliminate trachoma as a public health problem by using the "SAFE" strategy. While mathematical models are now standard tools used to support elimination efforts and there are a variety of models studying different aspects of trachoma transmission dynamics, the "F" component of the strategy corresponding to facial cleanliness has received very little attention so far. In this paper, we incorporate human behavior into a standard epidemiological model and develop a dynamical game during which individuals practice facial cleanliness based on their epidemiological status and perceived benefits and costs. We found that the number of infectious individuals generally increases with the difficulty to access a water source. However, this increase happens only during three transition periods and the prevalence stays constant otherwise. Consequently, improving access to water can help eliminate trachoma, but the improvement needs to be significant enough to cross at least one of the three transition thresholds; otherwise the improved access will have no noticeable effect.
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Affiliation(s)
- Mary Barazanji
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Janesah D. Ngo
- Department of Biology, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Jule A. Powe
- Department of Mathematics and Applied Mathematics, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Kimberley P. Schneider
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Jan Rychtář
- Department of Mathematics and Applied Mathematics, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Dewey Taylor
- Department of Mathematics and Applied Mathematics, Virginia Commonwealth University, Richmond, VA, United States of America
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Robinson A, Gomes LRDO, Abdurahman OS, Alemayehu W, Shuka G, Melese E, Guye M, Legesse D, Elias E, Temam K, Koro KH, Adugna D, Seife F, Aga MA, Sarah V, Lambert SM, Walker SL, Habtamu E, Solomon AW, Last A, Macleod D, Burton MJ, Logan JG. Evaluation of the efficacy of insecticide-treated scarves to protect children from the trachoma vector Musca sorbens (Diptera: Muscidae): A phase II randomised controlled trial in Oromia, Ethiopia. EClinicalMedicine 2022; 49:101487. [PMID: 35747196 PMCID: PMC9189873 DOI: 10.1016/j.eclinm.2022.101487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 05/05/2022] [Accepted: 05/16/2022] [Indexed: 11/18/2022] Open
Abstract
Background The eye-seeking fly Musca sorbens can act as a vector for ocular Chlamydia trachomatis, causing trachoma, yet there has been very little research on control measures. We investigated whether insect repellent products, specifically insecticide-treated clothing, could provide personal protection to the user from eye-seeking flies. Methods We first conducted a series of phase I laboratory studies to inform our choice of field intervention. We then conducted a phase II randomised controlled trial testing the efficacy of permethrin-treated scarves (PTS) in reducing fly-face contact in Oromia, Ethiopia. Children aged 4-10 years in full health and with no known adverse reactions to permethrin or other insecticides were allocated to either arm using restricted randomisation. Intervention arm children wore Insect Shield® versatile wraps (as PTS) for 28 days. The primary outcomes, fly-eye, -nose and -mouth contact, were assessed on the first day (0/30/60/180 minutes), on day 7 and on day 28. All participants present per timepoint were included in analyses. This trial was registered with ClinicalTrials.gov (NCT03813069). Findings Participants were recruited to the field trial between 29/10/2019 and 01/11/2019, 58 were randomised to test or control arm. More fly (-eye, -nose and -mouth) contacts were observed in the PTS arm at baseline. After adjusting for baseline contact rates, across all timepoints there was a 35% decrease in fly-eye contacts in the PTS relative to control arm (rate ratio [RR] 0.65, 95% CI 0.52-0.83). Similar cross-timepoint reductions were seen for fly-nose and fly-mouth contacts (RR 0.69, 95% CI 0.51-0.92 and RR 0.79, 95% CI 0.62-1.01, respectively). All children were included on day 0. Two in the control arm were absent on day 7, one left the study and four were excluded from analysis at day 28. No adverse events occurred in the trial. Interpretation Musca sorbens flies are sufficiently repelled by PTS to reduce fly-eye contacts for the wearer, thus possibly reducing the risk of trachoma transmission. Permethrin-treated scarves may therefore an alternative to insecticide space spraying for protection from these flies. Funding Wellcome Trust.
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Affiliation(s)
- Ailie Robinson
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Laura Reis de Oliveira Gomes
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Oumer Shafi Abdurahman
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Wondu Alemayehu
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Gemeda Shuka
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Ewunetu Melese
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Meseret Guye
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Demitu Legesse
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Eden Elias
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Kedir Temam
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Korso Hirpo Koro
- The Fred Hollows Foundation, P.O. Box 6307, Addis Ababa, Ethiopia
| | - Dereje Adugna
- Oromia Regional Health Bureau, Addis Ababa, Ethiopia
| | - Fikre Seife
- The Ethiopian Federal Ministry of Health, Disease Prevention and Control Directorate, Addis Ababa, Ethiopia
| | | | - Virginia Sarah
- Global Partnerships Executive, The Fred Hollows Foundation, 12-15 Crawford Mews, York Street, London W1H1LX
| | - Saba M. Lambert
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Stephen L. Walker
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Esmael Habtamu
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Avenue Appia 20, 1202 Genève, Switzerland
| | - Anna Last
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - David Macleod
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Matthew J. Burton
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
- National Institute for Health Research Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - James G. Logan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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Blumberg S, Borlase A, Prada JM, Solomon AW, Emerson P, Hooper PJ, Deiner MS, Amoah B, Hollingsworth TD, Porco TC, Lietman TM. Implications of the COVID-19 pandemic in eliminating trachoma as a public health problem. Trans R Soc Trop Med Hyg 2021; 115:222-228. [PMID: 33449114 PMCID: PMC7928550 DOI: 10.1093/trstmh/traa170] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/07/2020] [Accepted: 01/09/2021] [Indexed: 11/13/2022] Open
Abstract
Background Progress towards elimination of trachoma as a public health problem has been substantial, but the coronavirus disease 2019 (COVID-19) pandemic has disrupted community-based control efforts. Methods We use a susceptible-infected model to estimate the impact of delayed distribution of azithromycin treatment on the prevalence of active trachoma. Results We identify three distinct scenarios for geographic districts depending on whether the basic reproduction number and the treatment-associated reproduction number are above or below a value of 1. We find that when the basic reproduction number is <1, no significant delays in disease control will be caused. However, when the basic reproduction number is >1, significant delays can occur. In most districts, 1 y of COVID-related delay can be mitigated by a single extra round of mass drug administration. However, supercritical districts require a new paradigm of infection control because the current strategies will not eliminate disease. Conclusions If the pandemic can motivate judicious, community-specific implementation of control strategies, global elimination of trachoma as a public health problem could be accelerated.
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Affiliation(s)
- Seth Blumberg
- Francis I Proctor Foundation, University of California, San Francisco, San Francisco, CA, USA
| | | | - Joaquin M Prada
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Paul Emerson
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Pamela J Hooper
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Michael S Deiner
- Francis I Proctor Foundation, University of California, San Francisco, San Francisco, CA, USA
| | - Benjamin Amoah
- Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
| | | | - Travis C Porco
- Francis I Proctor Foundation, University of California, San Francisco, San Francisco, CA, USA.,Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
| | - Thomas M Lietman
- Francis I Proctor Foundation, University of California, San Francisco, San Francisco, CA, USA.,Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA.,Institute for Global Health Sciences, University of California, San Francisco, San Francisco, CA, USA.,Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
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Insights from mathematical modelling and quantitative analysis on the proposed 2030 goals for trachoma. Gates Open Res 2021; 3:1721. [PMID: 34027309 PMCID: PMC8111938 DOI: 10.12688/gatesopenres.13086.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2021] [Indexed: 01/21/2023] Open
Abstract
Trachoma is a neglected tropical disease and the leading infectious cause of blindness worldwide. The current World Health Organization goal for trachoma is elimination as a public health problem, defined as reaching a prevalence of trachomatous inflammation-follicular below 5% in children (1-9 years) and a prevalence of trachomatous trichiasis in adults below 0.2%. Current targets to achieve elimination were set to 2020 but are being extended to 2030. Mathematical and statistical models suggest that 2030 is a realistic timeline for elimination as a public health problem in most trachoma endemic areas. Although the goal can be achieved, it is important to develop appropriate monitoring tools for surveillance after having achieved the elimination target to check for the possibility of resurgence. For this purpose, a standardized serological approach or the use of multiple diagnostics in complement would likely be required.
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7
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Insights from mathematical modelling and quantitative analysis on the proposed 2030 goals for trachoma. Gates Open Res 2021; 3:1721. [PMID: 34027309 DOI: 10.12688/gatesopenres.13086.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/12/2019] [Indexed: 11/20/2022] Open
Abstract
Trachoma is a neglected tropical disease and the leading infectious cause of blindness worldwide. The current World Health Organization goal for trachoma is elimination as a public health problem, defined as reaching a prevalence of trachomatous inflammation-follicular below 5% in children (1-9 years) and a prevalence of trachomatous trichiasis in adults below 0.2%. Current targets to achieve elimination were set to 2020 but are being extended to 2030. Mathematical and statistical models suggest that 2030 is a realistic timeline for elimination as a public health problem in most trachoma endemic areas. Although the goal can be achieved, it is important to develop appropriate monitoring tools for surveillance after having achieved the elimination target to check for the possibility of resurgence. For this purpose, a standardized serological approach or the use of multiple diagnostics in complement would likely be required.
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8
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Nash SD, Astale T, Nute AW, Bethea D, Chernet A, Sata E, Zerihun M, Gessese D, Ayenew G, Ayele Z, Melak B, Haile M, Zeru T, Tadesse Z, Arnold BF, Callahan EK, Martin DL. Population-Based Prevalence of Chlamydia trachomatis Infection and Antibodies in Four Districts with Varying Levels of Trachoma Endemicity in Amhara, Ethiopia. Am J Trop Med Hyg 2021; 104:207-215. [PMID: 33200728 PMCID: PMC7790060 DOI: 10.4269/ajtmh.20-0777] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The Trachoma Control Program in Amhara region, Ethiopia, scaled up the surgery, antibiotics, facial cleanliness, and environmental improvement (SAFE) strategy in all districts starting in 2007. Despite these efforts, many districts still require additional years of SAFE. In 2017, four districts were selected for the assessment of antibody responses against Chlamydia trachomatis antigens and C. trachomatis infection to better understand transmission. Districts with differing endemicity were chosen, whereby one had a previous trachomatous inflammation-follicular (TF) prevalence of ≥ 30% (Andabet), one had a prevalence between 10% and 29.9% (Dera), one had a prevalence between 5% and 10% (Woreta town), and one had a previous TF prevalence of < 5% (Alefa) and had not received antibiotic intervention for 2 years. Survey teams assessed trachoma clinical signs and took conjunctival swabs and dried blood spots (DBS) to measure infection and antibody responses. Trachomatous inflammation-follicular prevalence among children aged 1–9 years was 37.0% (95% CI: 31.1–43.3) for Andabet, 14.7% (95% CI: 10.0–20.5) for Dera, and < 5% for Woreta town and Alefa. Chlamydia trachomatis infection was only detected in Andabet (11.3%). Within these districts, 2,195 children provided DBS. The prevalence of antibody responses to the antigen Pgp3 was 36.9% (95% CI: 29.0–45.6%) for Andabet, 11.3% (95% CI: 5.9–20.6%) for Dera, and < 5% for Woreta town and Alefa. Seroconversion rate for Pgp3 in Andabet was 0.094 (95% CI: 0.069–0.128) events per year. In Andabet district, where SAFE implementation has occurred for 11 years, the antibody data support the finding of persistently high levels of trachoma transmission.
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Affiliation(s)
- Scott D Nash
- 1Trachoma Control Program, The Carter Center, Atlanta, Georgia
| | - Tigist Astale
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Andrew W Nute
- 1Trachoma Control Program, The Carter Center, Atlanta, Georgia
| | - Danaya Bethea
- 3Centers for Disease Control and Prevention, DPD, Atlanta, Georgia
| | - Ambahun Chernet
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Eshetu Sata
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Mulat Zerihun
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Demelash Gessese
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Gedefaw Ayenew
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Zebene Ayele
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Berhanu Melak
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Mahteme Haile
- 4Amhara Public Health Institute, Research and Technology Transfer Directorate, Bahir Dar, Ethiopia
| | - Taye Zeru
- 4Amhara Public Health Institute, Research and Technology Transfer Directorate, Bahir Dar, Ethiopia
| | - Zerihun Tadesse
- 2Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Benjamin F Arnold
- 5Francis I. Proctor Foundation, University of California San Francisco, San Francisco, California.,6Department of Ophthalmology, University of California San Francisco, San Francisco, California
| | | | - Diana L Martin
- 3Centers for Disease Control and Prevention, DPD, Atlanta, Georgia
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9
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Sata E, Nute AW, Astale T, Gessese D, Ayele Z, Zerihun M, Chernet A, Melak B, Jensen KA, Haile M, Zeru T, Beyen M, Dawed AA, Seife F, Tadesse Z, Callahan EK, Ngondi J, Nash SD. Twelve-Year Longitudinal Trends in Trachoma Prevalence among Children Aged 1-9 years in Amhara, Ethiopia, 2007-2019. Am J Trop Med Hyg 2021; 104:1278-1289. [PMID: 33534757 PMCID: PMC8045658 DOI: 10.4269/ajtmh.20-1365] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 11/23/2020] [Indexed: 11/07/2022] Open
Abstract
Trachoma control in the Amhara region of Ethiopia, where all districts were once endemic, began in 2001 and attained full scale-up of the Surgery, Antibiotics, Facial cleanliness, and Environmental improvement (SAFE) strategy by 2010. Since scaling up, the program has distributed approximately 14 million doses of antibiotic per year, implemented village- and school-based health education, and promoted latrine construction. This report aims to provide an update on the prevalence of trachoma among children aged 1-9 years as of the most recent impact or surveillance survey in all 160 districts of Amhara. As of 2019, 45 (28%) districts had a trachomatous inflammation-follicular (TF) prevalence below the 5% elimination threshold. There was a statistically significant relationship between TF prevalence observed at the first impact survey (2010-2015) and eventual achievement of TF < 5% (2015-2019). Of the 26 districts with a first impact survey < 10% TF, 20 (76.9%) had < 5% TF at the most recent survey. Of the 75 districts with a first survey between 10% and 29.9% TF, 21 (28.0%) had < 5% TF at the most recent survey. Finally, among 59 districts ≥ 30% TF at the first survey, four (6.8%) had < 5% TF by 2019. As of 2019, 30 (18.8%) districts remained with TF ≥ 30%. Amhara has seen considerable reductions of trachoma since the start of the program. A strong commitment to the SAFE strategy coupled with data-driven enhancements to that strategy is necessary to facilitate timely elimination of trachoma as a public health problem regionally in Amhara and nationwide in Ethiopia.
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Affiliation(s)
- Eshetu Sata
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Andrew W Nute
- 2Trachoma Control Program, The Carter Center, Atlanta, Georgia
| | - Tigist Astale
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Demelash Gessese
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Zebene Ayele
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Mulat Zerihun
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Ambahun Chernet
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Berhanu Melak
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | | | - Mahteme Haile
- 3Amhara Public Health Institute, Research and Technology Transfer Directorate, Bahir Dar, Ethiopia
| | - Taye Zeru
- 3Amhara Public Health Institute, Research and Technology Transfer Directorate, Bahir Dar, Ethiopia
| | - Melkamu Beyen
- 4Amhara Regional Health Bureau, Health Promotion and Disease Prevention, Bahir Dar, Ethiopia
| | - Adisu Abebe Dawed
- 4Amhara Regional Health Bureau, Health Promotion and Disease Prevention, Bahir Dar, Ethiopia
| | - Fikre Seife
- 5Federal Ministry of Health, Disease Prevention and Control Directorate, Addis Ababa, Ethiopia
| | - Zerihun Tadesse
- 1Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | | | - Jeremiah Ngondi
- 6RTI International, International Development (Global Health), London, United Kingdom
| | - Scott D Nash
- 2Trachoma Control Program, The Carter Center, Atlanta, Georgia
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10
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Solomon AW, Hooper PJ, Bangert M, Mwingira UJ, Bakhtiari A, Brady MA, Fitzpatrick C, Jones I, Kabona G, Kello AB, Millar T, Mosher AW, Ngondi JM, Nshala A, Renneker K, Rotondo LA, Stelmach R, Harding-Esch EM, Malecela MN. The Importance of Failure: How Doing Impact Surveys That Fail Saves Trachoma Programs Money. Am J Trop Med Hyg 2020; 103:2481-2487. [PMID: 33025878 PMCID: PMC7695084 DOI: 10.4269/ajtmh.20-0686] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Trachoma programs use annual antibiotic mass drug administration (MDA) in evaluation units (EUs) that generally encompass 100,000–250,000 people. After one, three, or five MDA rounds, programs undertake impact surveys. Where impact survey prevalence of trachomatous inflammation—follicular (TF) in 1- to 9-year-olds is ≥ 5%, ≥ 1 additional MDA rounds are recommended before resurvey. Impact survey costs, and the proportion of impact surveys returning TF prevalence ≥ 5% (the failure rate or, less pejoratively, the MDA continuation rate), therefore influence the cost of eliminating trachoma. We modeled, for illustrative EU sizes, the financial cost of undertaking MDA with and without conducting impact surveys. As an example, we retrospectively assessed how conducting impact surveys affected costs in the United Republic of Tanzania for 2017–2018. For EUs containing 100,000 people, the median (interquartile range) cost of continuing MDA without doing impact surveys is USD 28,957 (17,581–36,197) per EU per year, whereas continuing MDA solely where indicated by impact survey results costs USD 17,564 (12,158–21,694). If the mean EU population is 100,000, then continuing MDA without impact surveys becomes advantageous in financial cost terms only when the continuation rate exceeds 71%. For the United Republic of Tanzania in 2017–2018, doing impact surveys saved enough money to provide MDA for > 1,000,000 people. Although trachoma impact surveys have a nontrivial cost, they generally save money, providing EUs have > 50,000 inhabitants, the continuation rate is not excessive, and they generate reliable data. If all EUs pass their impact surveys, then we have waited too long to do them.
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Affiliation(s)
- Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Pamela J Hooper
- Task Force for Global Health, International Trachoma Initiative, Atlanta, Georgia
| | - Mathieu Bangert
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Upendo J Mwingira
- Neglected Tropical Disease Control Program, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, United Republic of Tanzania
| | - Ana Bakhtiari
- Task Force for Global Health, International Trachoma Initiative, Atlanta, Georgia
| | | | - Christopher Fitzpatrick
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Iain Jones
- Sightsavers, Haywards Heath, United Kingdom
| | - George Kabona
- Neglected Tropical Disease Control Program, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, United Republic of Tanzania
| | - Amir B Kello
- Expanded Special Project for Elimination of Neglected Tropical Diseases, World Health Organization Regional Office for Africa, Brazzaville, Congo
| | - Tom Millar
- Sightsavers, Haywards Heath, United Kingdom
| | - Aryc W Mosher
- United States Agency for International Development, Washington, District of Columbia
| | | | - Andreas Nshala
- Department of International Maternal and Child Health, Faculty of Medicine and Pharmacy, University of Uppsala, Uppsala, Sweden.,IMA World Health, Dar es Salaam, United Republic of Tanzania
| | - Kristen Renneker
- Task Force for Global Health, International Trachoma Initiative, Atlanta, Georgia
| | | | | | - Emma M Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Mwelecele N Malecela
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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11
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Nasir MA, Elsawy F, Omar A, Haque SO, Nadir R. Eliminating Trachoma by 2020: Assessing Progress in Nigeria. Cureus 2020; 12:e9450. [PMID: 32760636 PMCID: PMC7392186 DOI: 10.7759/cureus.9450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Trachoma is a neglected tropical disease that causes an eye infection which can lead to blindness if left untreated. In 1998, the World Health Organisation (WHO) launched a new goal to eradicate trachoma by 2020. Over the years, in partnership with the WHO, an effective strategy plan was devised to help tackle and control the disease. This involved surgery for trichiasis, antibiotic treatment, facial cleanliness, and environmental improvement (SAFE). Consequently, the number of people affected by trachoma has significantly decreased in recent times. Despite this, trachoma remains a major public health concern in 44 countries worldwide, including Nigeria. Although improvements have been seen throughout Nigeria, the disjointed application of the SAFE strategy has delayed progress compared to other countries. Providing quality treatment to those with trachoma, in addition to improving preventative measures are challenges faced throughout the country. However, a multi-pronged approach emulating the methods of other countries is recommended to achieve trachoma elimination. This review aims to evaluate the progress and challenges faced in Nigeria with regards to eliminating trachoma.
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Affiliation(s)
| | - Fayez Elsawy
- Medicine, Manchester University, Manchester, GBR
| | | | - Shah O Haque
- Medicine, Manchester University, Manchester, GBR
| | - Rans Nadir
- Medicine, Imperial College London, London, GBR
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12
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Nash SD, Chernet A, Moncada J, Stewart AEP, Astale T, Sata E, Zerihun M, Gessese D, Melak B, Ayenew G, Ayele Z, Chanyalew M, Lietman TM, Callahan EK, Schachter J, Tadesse Z. Ocular Chlamydia trachomatis infection and infectious load among pre-school aged children within trachoma hyperendemic districts receiving the SAFE strategy, Amhara region, Ethiopia. PLoS Negl Trop Dis 2020; 14:e0008226. [PMID: 32421719 PMCID: PMC7259799 DOI: 10.1371/journal.pntd.0008226] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 05/29/2020] [Accepted: 03/17/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND After approximately 5 years of SAFE (surgery, antibiotics, facial cleanliness, environmental improvement) interventions for trachoma, hyperendemic (trachomatous inflammation-follicular (TF) ≥30%) districts remained in Amhara, Ethiopia. This study's aim was to characterize the epidemiology of Chlamydia trachomatis (Ct) infection and load among pre-school aged children living under the SAFE strategy. METHODS Conjunctival swabs from a population-based sample of children aged 1-5 years collected between 2011 and 2015 were assayed to provide Ct infection data from 4 endemic zones (comprised of 58 districts). Ct load was determined using a calibration curve. Children were graded for TF and trachomatous inflammation-intense (TI). RESULTS 7,441 children were swabbed in 4 zones. TF and TI prevalence were 39.9% (95% confidence Interval [CI]: 37.5%, 42.4%), and 9.2% (95% CI: 8.1%, 10.3%) respectively. Ct infection prevalence was 6.0% (95% CI: 5.0%, 7.2%). Infection was highest among children aged 2 to 4 years (6.6%-7.0%). Approximately 10% of infection occurred among children aged 1 year. Ct load decreased with age (P = 0.002), with the highest loads observed in children aged 1 year (P = 0.01) vs. aged 5 years. Participants with TF (P = 0.20) and TI (P<0.01) had loads greater than individuals without active trachoma. CONCLUSIONS In this hyperendemic setting, it appears that the youngest children may contribute in meaningful ways towards persistent active trachoma.
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Affiliation(s)
- Scott D. Nash
- Trachoma Control Program, The Carter Center, Atlanta, United States of America
| | - Ambahun Chernet
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Jeanne Moncada
- Department of Laboratory Medicine, University of California, San Francisco, United States of America
| | - Aisha E. P. Stewart
- Trachoma Control Program, The Carter Center, Atlanta, United States of America
| | - Tigist Astale
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Eshetu Sata
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Mulat Zerihun
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Demelash Gessese
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Berhanu Melak
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Gedefaw Ayenew
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Zebene Ayele
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Melsew Chanyalew
- Health Promotion and Disease Prevention Core Process, Amhara Regional Health Bureau, Bahir Dar, Ethiopia
| | - Thomas M. Lietman
- Francis I. Proctor Foundation, University of California, San Francisco, United States of America
| | - E. Kelly Callahan
- Trachoma Control Program, The Carter Center, Atlanta, United States of America
| | - Julius Schachter
- Department of Laboratory Medicine, University of California, San Francisco, United States of America
| | - Zerihun Tadesse
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
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13
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Lietman TM, Pinsent A, Liu F, Deiner M, Hollingsworth TD, Porco TC. Models of Trachoma Transmission and Their Policy Implications: From Control to Elimination. Clin Infect Dis 2019; 66:S275-S280. [PMID: 29860288 PMCID: PMC5982784 DOI: 10.1093/cid/ciy004] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Despite great progress in eliminating trachoma from the majority of worldwide districts, trachoma control seems to have stalled in some endemic districts. Can mathematical models help suggest the way forward? We review specific achievements of models in trachoma control in the past. Models showed that, even with incomplete coverage, mass drug administration could eliminate disease through a spillover effect, somewhat analogous to how incomplete vaccine campaigns can eliminate disease through herd protection. Models also suggest that elimination can always be achieved if enough people are treated often enough with an effective enough drug. Other models supported the idea that targeting ages at highest risk or continued improvements in hygiene and sanitation can contribute meaningfully to trachoma control. Models of intensive targeting of a core group may point the way to final eradication even in areas with substantial transmission and within-community heterogeneity.
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Affiliation(s)
- Thomas M Lietman
- Francis I. Proctor Foundation, San Francisco.,Department of Ophthalmology, San Francisco.,Department of Epidemiology and Biostatistics, San Francisco.,Global Health Sciences, University of California, San Francisco
| | - Amy Pinsent
- School of Public Health and Preventative Medicine, Monash University, Melbourne, Australia
| | | | - Michael Deiner
- Francis I. Proctor Foundation, San Francisco.,Department of Ophthalmology, San Francisco
| | - T Deirdre Hollingsworth
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, United Kingdom
| | - Travis C Porco
- Francis I. Proctor Foundation, San Francisco.,Department of Ophthalmology, San Francisco.,Department of Epidemiology and Biostatistics, San Francisco
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14
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Alada JJ, Mpyet C, Florea VV, Boisson S, Willis R, Bakhtiari A, Muhammad N, Adamu MD, Umar MM, Olobio N, Isiyaku S, Adamani W, Amdife D, Solomon AW. Prevalence of Trachoma in Kogi State, Nigeria: Results of four Local Government Area-Level Surveys from the Global Trachoma Mapping Project. Ophthalmic Epidemiol 2019; 25:33-40. [PMID: 30806551 PMCID: PMC6444201 DOI: 10.1080/09286586.2017.1409359] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE To determine the prevalence of trachoma in four Local Government Areas (LGAs) of Kogi State, Nigeria. METHODS In June 2014, we conducted population-based, cross-sectional surveys according to Global Trachoma Mapping Project (GTMP) protocols in selected LGAs of Kogi State. In each LGA, 25 clusters were selected with probability proportional to size. In each of these clusters, 25 households were enrolled for the survey. All residents of selected households aged ≥1 year were examined by GTMP-certified graders for trachomatous inflammation-follicular (TF) and trichiasis using the simplified trachoma grading scheme. Data on sources of household water and types of sanitation facilities were collected through questioning and direct observation. RESULTS The age-adjusted TF prevalence in 1-9-year-olds ranged from 0.4% (95% CI 0.1-0.8%) in Bassa to 1.0% (95% CI 0.3-1.9%) in Omala. Across all four LGAs, only one case of trichiasis was found; this individual was in Omala, giving that LGA a trichiasis prevalence in individuals aged ≥15 years of 0.02% (95% CI 0.00-0.07%). Between 77 and 88% of households had access to water for hygiene purposes, while only 10-30% had access to improved sanitation facilities. CONCLUSION Trachoma is not a public health problem in any of the 4 LGAs surveyed. There is, however, the need to increase access to adequate water and sanitation services to contribute to the health and social and economic well-being of these communities.
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Affiliation(s)
- Joel J Alada
- a Department of Ophthalmology , Federal Medical Centre , Makurdi , Nigeria
| | - Caleb Mpyet
- b Department of Ophthalmology , University of Jos , Jos , Nigeria.,c Sightsavers , Kaduna , Nigeria.,d Kilimanjaro Centre for Community Ophthalmology International, Division of Ophthalmology , University of Cape Town , Cape Town , South Africa
| | - Victor V Florea
- e Department of Control of Neglected Tropical Diseases , World Health Organization , Geneva , Switzerland
| | - Sophie Boisson
- f Department of Public Health, the Environment and Social Determinants of Health , World Health Organization , Geneva , Switzerland
| | - Rebecca Willis
- g International Trachoma Initiative, Task Force for Global Health , Decatur , GA , USA
| | - Ana Bakhtiari
- g International Trachoma Initiative, Task Force for Global Health , Decatur , GA , USA
| | - Nasiru Muhammad
- h Ophthalmology Unit, Surgery Department , Usmanu Danfodiyo University , Sokoto , Nigeria
| | - Mohammed D Adamu
- h Ophthalmology Unit, Surgery Department , Usmanu Danfodiyo University , Sokoto , Nigeria
| | | | | | | | | | | | - Anthony W Solomon
- e Department of Control of Neglected Tropical Diseases , World Health Organization , Geneva , Switzerland.,l Clinical Research Department , London School of Hygiene & Tropical Medicine , London , United Kingdom.,m London Centre for Neglected Tropical Disease Research , London , United Kingdom
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15
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Astale T, Sata E, Zerihun M, Nute AW, Stewart AEP, Gessese D, Ayenew G, Melak B, Chanyalew M, Tadesse Z, Callahan EK, Nash SD. Population-based coverage survey results following the mass drug administration of azithromycin for the treatment of trachoma in Amhara, Ethiopia. PLoS Negl Trop Dis 2018; 12:e0006270. [PMID: 29451881 PMCID: PMC5833287 DOI: 10.1371/journal.pntd.0006270] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 03/01/2018] [Accepted: 01/25/2018] [Indexed: 11/18/2022] Open
Abstract
Background Trachoma is the leading infectious cause of blindness worldwide. In communities where the district level prevalence of trachomatous inflammation-follicular among children ages 1–9 years is ≥5%, WHO recommends annual mass drug administration (MDA) of antibiotics with the aim of at least 80% coverage. Population-based post-MDA coverage surveys are essential to understand the effectiveness of MDA programs, yet published reports from trachoma programs are rare. Methods In the Amhara region of Ethiopia, a population-based MDA coverage survey was conducted 3 weeks following the 2016 MDA to estimate the zonal prevalence of self-reported drug coverage in all 10 administrative zones. Survey households were selected using a multi-stage cluster random sampling design and all individuals in selected households were presented with a drug sample and asked about taking the drug during the campaign. Zonal estimates were weighted and confidence intervals were calculated using survey procedures. Self-reported drug coverage was then compared with regional reported administrative coverage. Results Region-wide, 24,248 individuals were enumerated, of which, 20,942 (86.4%) individuals were present. The regional self-reported antibiotic coverage was 76.8% (95%Confidence Interval (CI):69.3–82.9%) in the population overall and 77.4% (95%CI = 65.7–85.9%) among children ages 1–9 years old. Zonal coverage ranged from 67.8% to 90.2%. Five out of 10 zones achieved a coverage >80%. In all zones, the reported administrative coverage was greater than 90% and was considerably higher than self-reported MDA coverage. Main reasons reported for MDA campaign non-attendance included being physically unable to get to MDA site (22.5%), traveling (20.6%), and not knowing about the campaign (21.0%). MDA refusal was low (2.8%) in this population. Conclusions Although self-reported MDA coverage in Amhara was greater than 80% in some zones, programmatic improvements are warranted throughout Amhara to achieve higher coverage. These results will be used to enhance community mobilization and improve training for MDA distributors and supervisors to improve coverage in future MDAs. Mass drug administration (MDA) with antibiotics is a key component of the trachoma control strategy. The World Health Organization (WHO) recommends that at least 80% of the target population should be reached with MDA. Drug coverage estimates from population-based surveys may increase our understanding of factors affecting the effectiveness of MDA. We conducted a region-wide population-based survey to estimate the prevalence of self-reported drug coverage in all ten administrative zones of Amhara region, an area with a population of approximately 21 million people. The self-reported drug coverage was greater than 80% in five of the ten zones and was 76.8% region-wide. Zonal administrative coverage reports were greater than 90% and were considerably higher than self-reported coverage in all zones. The discrepancy between administrative and self-report coverages also suggest that efforts should be made to better understand the reasons for the disparity in the two measures. The main reasons reported for not attending the MDA included being physically unable to get to the distribution site, traveling during the campaign, and lack of knowledge about the campaign. These findings suggest that making the distribution site accessible to all individuals, informing constituents about timing of the campaign to allow for travel, and providing adequate information about the campaign would improve MDA participation.
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Affiliation(s)
- Tigist Astale
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
- * E-mail:
| | - Eshetu Sata
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Mulat Zerihun
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Andrew W. Nute
- Trachoma Control Program, The Carter Center, Atlanta, Georgia, United States of America
| | - Aisha E. P. Stewart
- Trachoma Control Program, The Carter Center, Atlanta, Georgia, United States of America
| | - Demelash Gessese
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Gedefaw Ayenew
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Berhanu Melak
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - Melsew Chanyalew
- Health Promotion and Disease Prevention Core Process, The Amhara Regional Health Bureau, Bahir Dar, Ethiopia
| | - Zerihun Tadesse
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | - E. Kelly Callahan
- Trachoma Control Program, The Carter Center, Atlanta, Georgia, United States of America
| | - Scott D. Nash
- Trachoma Control Program, The Carter Center, Atlanta, Georgia, United States of America
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16
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Delea MG, Solomon H, Solomon AW, Freeman MC. Interventions to maximize facial cleanliness and achieve environmental improvement for trachoma elimination: A review of the grey literature. PLoS Negl Trop Dis 2018; 12:e0006178. [PMID: 29370169 PMCID: PMC5800663 DOI: 10.1371/journal.pntd.0006178] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 02/06/2018] [Accepted: 12/19/2017] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Efforts are underway to scale-up the facial cleanliness and environmental improvement (F&E) components of the World Health Organization's SAFE strategy for elimination of trachoma as a public health problem. Improving understanding of the F&E intervention landscape could inform advancements prior to scale-up, and lead to more effective and sustained behavior change. METHODS/FINDINGS We systematically searched for relevant grey literature published from January 1965 through August 2016. Publications were eligible for review if they described interventions addressing F&E in the context of trachoma elimination programs. Subsequent to screening, we mapped attributes of F&E interventions. We then employed three behavior change frameworks to synthesize mapped data and identify potential intervention gaps. We identified 27 documents meeting inclusion criteria. With the exception of some recent programming, F&E interventions have largely focused on intermediate and distal antecedents of behavior change. Evidence from our analyses suggests many interventions are not designed to address documented determinants of improved F&E practices. No reviewed documents endorsed inclusion of intervention components related to behavioral maintenance or resilience-factors critical for sustaining improved behaviors. CONCLUSIONS If left unaddressed, identified gaps in intervention content may continue to challenge uptake and sustainability of improved F&E behaviors. Stakeholders designing and implementing trachoma elimination programs should review their F&E intervention content and delivery approaches with an eye toward improvement, including better alignment with established behavior change theories and empirical evidence. Implementation should move beyond information dissemination, and appropriately employ a variety of behavior change techniques to address more proximal influencers of change.
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Affiliation(s)
- Maryann G. Delea
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
- Department of Disease Control, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Hiwote Solomon
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Matthew C. Freeman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
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17
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Last AR, Burr SE, Harding-Esch E, Cassama E, Nabicassa M, Roberts CH, Mabey DCW, Holland MJ, Bailey RL. The impact of a single round of community mass treatment with azithromycin on disease severity and ocular Chlamydia trachomatis load in treatment-naïve trachoma-endemic island communities in West Africa. Parasit Vectors 2017; 10:624. [PMID: 29282126 PMCID: PMC5745817 DOI: 10.1186/s13071-017-2566-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 12/03/2017] [Indexed: 10/29/2022] Open
Abstract
BACKGROUND Trachoma, a neglected tropical disease, is caused by ocular infection with Chlamydia trachomatis (Ct). The World Health Organization (WHO) recommends three annual rounds of community mass drug treatment with azithromycin (MDA) if the prevalence of follicular trachoma in 1-9 year olds (TF1-9) exceeds 10% at district level to achieve an elimination target of district-level TF1-9 below 5% after. To evaluate this strategy in treatment-naïve trachoma-endemic island communities in Guinea Bissau, we conducted a cross-sectional population-based trachoma survey on four islands. The upper tarsal conjunctivae of each participant were clinically assessed for trachoma and conjunctival swabs were obtained (n = 1507). We used a droplet digital PCR assay to detect Ct infection and estimate bacterial load. We visited the same households during a second cross-sectional survey and repeated the ocular examination and obtained conjunctival swabs from these households one year after MDA (n = 1029). RESULTS Pre-MDA TF1-9 was 22.0% (136/618). Overall Ct infection prevalence (CtI) was 18.6% (25.4% in 1-9 year olds). Post-MDA (estimated coverage 70%), TF1-9 and CtI were significantly reduced (7.4% (29/394, P < 0.001) and 3.3% (34/1029, P < 0.001) (6.6% in 1-9 year olds, P < 0.001), respectively. Median ocular Ct load was reduced from 2038 to 384 copies/swab (P < 0.001). Following MDA cases of Ct infection were highly clustered (Moran's I 0.27, P < 0.001), with fewer clusters of Ct infection overall, fewer clusters of cases with high load infections and less severe disease. CONCLUSIONS Despite a significant reduction in the number of clusters of Ct infection, mean Ct load, disease severity and presence of clusters of cases of high load Ct infection suggesting the beginning of trachoma control in isolated island communities, following a single round of MDA we demonstrate that transmission is still ongoing. These detailed data are useful in understanding the epidemiology of ocular Ct infection in the context of MDA and the tools employed may have utility in determining trachoma elimination and surveillance activities in similar settings.
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Affiliation(s)
- Anna R Last
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Sarah E Burr
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Disease Control and Elimination Theme, Medical Research Council Unit The Gambia, P.OBox 273, Banjul, Atlantic Boulevard, Fajara, The, Gambia
| | - Emma Harding-Esch
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Eunice Cassama
- Programa Nacional de Saúde de Visão, Ministério de Saúde Publica, P.O. Box 50, Avenida de Unidade Africana, Bisssau, Guinea-Bissau
| | - Meno Nabicassa
- Programa Nacional de Saúde de Visão, Ministério de Saúde Publica, P.O. Box 50, Avenida de Unidade Africana, Bisssau, Guinea-Bissau
| | - Chrissy H Roberts
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - David C W Mabey
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Martin J Holland
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Robin L Bailey
- Clinical Research Department, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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18
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Pinsent A, Liu F, Deiner M, Emerson P, Bhaktiari A, Porco TC, Lietman T, Gambhir M. Probabilistic forecasts of trachoma transmission at the district level: A statistical model comparison. Epidemics 2017; 18:48-55. [PMID: 28279456 PMCID: PMC5340843 DOI: 10.1016/j.epidem.2017.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 01/20/2017] [Accepted: 01/31/2017] [Indexed: 11/09/2022] Open
Abstract
The World Health Organization and its partners are aiming to eliminate trachoma as a public health problem by 2020. In this study, we compare forecasts of TF prevalence in 2011 for 7 different statistical and mechanistic models across 9 de-identified trachoma endemic districts, representing 4 unique trachoma endemic countries. We forecast TF prevalence between 1-6 years ahead in time and compare the 7 different models to the observed 2011 data using a log-likelihood score. An SIS model, including a district-specific random effect for the district-specific transmission coefficient, had the highest log-likelihood score across all 9 districts and was therefore the best performing model. While overall the deterministic transmission model was the least well performing model, although it did comparably well to the other models for 8 of 9 districts. We perform a statistically rigorous comparison of the forecasting ability of a range of mathematical and statistical models across multiple endemic districts between 1 and 6 years ahead of the last collected TF prevalence data point in 2011, assessing results against surveillance data. This study is a step towards making statements about likelihood and time to elimination with regard to the WHO GET2020 goals.
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Affiliation(s)
- Amy Pinsent
- Department of Public Health and Preventative Medicine, Monash University, Melbourne, Australia.
| | - Fengchen Liu
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, CA, USA
| | - Michael Deiner
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, CA, USA; Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA
| | - Paul Emerson
- International Trachoma Initiative, Atlanta, GA, USA; School of Public Health, Emory University, Atlanta, GA, USA
| | | | - Travis C Porco
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, CA, USA; Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA; Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA
| | - Thomas Lietman
- F.I. Proctor Foundation, University of California San Francisco, San Francisco, CA, USA; Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA; Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA; Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Manoj Gambhir
- Department of Public Health and Preventative Medicine, Monash University, Melbourne, Australia
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Pinsent A, Gambhir M. Improving our forecasts for trachoma elimination: What else do we need to know? PLoS Negl Trop Dis 2017; 11:e0005378. [PMID: 28182664 PMCID: PMC5321453 DOI: 10.1371/journal.pntd.0005378] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 02/22/2017] [Accepted: 02/01/2017] [Indexed: 11/20/2022] Open
Abstract
The World Health Organization (WHO) has targeted trachoma for elimination as a public health concern by 2020. Mathematical modelling is used for a range of infectious diseases to assess the impact of different intervention strategies on the prevalence of infection or disease. Here we evaluate the performance of four different mechanistic mathematical models that could all realistically represent trachoma transmission. We fit the four different mechanistic models of trachoma transmission to cross-sectional age-specific Polymerase Chain Reaction (PCR) and Trachomatous inflammation, follicular (TF) prevalence data. We estimate 4 or 3 parameters within each model, including the duration of an individual's infection and disease episode using Markov Chain Monte Carlo. We assess the performance of each models fit to the data by calculating the deviance information criterion. We then model the implementation of different interventions for each model structure to assess the feasibility of elimination of trachoma with different model structures. A model structure which allowed some re-infection in the disease state (Model 2) was statistically the most well performing model. All models struggled to fit to the very high prevalence of active disease in the youngest age group. Our simulations suggested that for Model 3, with annual antibiotic treatment and transmission reduction, the chance of reducing active disease prevalence to < 5% within 5 years was very low, while Model 2 and 4 could ensure that active disease prevalence was reduced within 5 years. Model 2 here fitted to the data best of the models evaluated. The appropriate level of susceptibility to re-infection was, however, challenging to identify given the amount and kind of data available. We demonstrate that the model structure assumed can lead to different end points following the implementation of the same interventions. Our findings are likely to extend beyond trachoma and should be considered when modelling other neglected tropical diseases.
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Affiliation(s)
- Amy Pinsent
- Department of Epidemiology and Preventive Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
| | - Manoj Gambhir
- Department of Epidemiology and Preventive Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria, Australia
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Mohammadpour M, Abrishami M, Masoumi A, Hashemi H. Trachoma: Past, present and future. J Curr Ophthalmol 2016; 28:165-169. [PMID: 27830198 PMCID: PMC5093790 DOI: 10.1016/j.joco.2016.08.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 11/19/2022] Open
Abstract
Purpose To review the background, epidemiology and current management of trachoma in endemic areas and worldwide. Methods Review of literature. Results Trachoma is one of the leading causes of preventable blindness in developing countries. It was reported as one of the seven most neglected tropical diseases that can be prevented via drug administration. Its infliction is primarily aimed at those living in areas deprived of clean water and proper sanitation. It is estimated that trachoma is the cause of visual impairment in about 2.2 million people worldwide of which about 1.2 million are completely blind. With implementation of the SAFE (surgery, antibiotics, facial cleanliness, and environmental control) strategy with support from the International Trachoma Initiative (ITI) the incidence of trachoma has decreased significantly in the Middle East and North Africa region. Conclusion With the enhancement of socioeconomic and sanitary status of people, advent of new generations of antibiotics, training of expert ophthalmologists and eye care facilities the prevalence of trachoma is decreasing.
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Affiliation(s)
- Mehrdad Mohammadpour
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
- Corresponding author.
| | - Mojtaba Abrishami
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Masoumi
- Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
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