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Bromfield JA, Aguwa UT, Sata E, Jensen KA, Mihretu F, Callahan EK, West SK, Wolle MA, Nash SD. Severity of Trachomatous Scarring among Adults in Trachoma-Endemic Amhara Region of Ethiopia. Am J Trop Med Hyg 2024; 111:121-126. [PMID: 38917786 PMCID: PMC11376122 DOI: 10.4269/ajtmh.23-0894] [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: 12/18/2023] [Accepted: 04/08/2024] [Indexed: 06/27/2024] Open
Abstract
Trachomatous scarring has been shown to progress regardless of active ocular Chlamydia trachomatis infection, indicating that scarring drivers may be unrelated to ongoing transmission. Although scarring prevalence is commonly associated with older age and female sex, less is known about other potential contributors to its development. This study identified and assessed risk factors associated with scarring magnitude in a trachoma-endemic setting, utilizing a five-point photographic scale (S0-S4). During 2017 trachoma surveys of Amhara, Ethiopia, photographers captured left and right conjunctival images of adults (ages 15 years and older) from 10 districts. Subsequently, two graders independently assessed photographs for scarring, with discrepancies adjudicated by an expert grader. Scarring scores for 729 individuals were aggregated from the eye level to the participant level, excluding 17 participants because of poor photograph quality. Among those with scarring, most cases (20.4%) were severe (S4, comprising more than 90% of the tarsal conjunctiva) compared with the prevalence of moderate S3-A/B (11.2%), S2 (8.3%), and mild S1 (19.2%). The youngest group (ages 15-19 years) exhibited all scarring stages. Older participants (60 years and older) experienced a greater burden of severe scarring (S4 prevalence: 32.6%) than their younger (15-19 years) counterparts (6.2%). Multivariate ordinal logistic regression models indicated female sex, increasing age, and district-level trachomatous follicular-inflammation prevalence were significant predictors of scarring severity. Trachomatous scarring and its progression to trichiasis, may prove a barrier to meeting WHO timelines for trachoma elimination and will necessitate ongoing surveillance and interventions after elimination thresholds have been met.
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Affiliation(s)
| | - Ugochi T Aguwa
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland
| | - Eshetu Sata
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | | | - Fetene Mihretu
- Trachoma Control Program, The Carter Center, Addis Ababa, Ethiopia
| | | | - Sheila K West
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland
| | - Meraf A Wolle
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland
| | - Scott D Nash
- Trachoma Control Program, The Carter Center, Atlanta, Georgia
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Toumasis P, Vrioni G, Tsinopoulos IT, Exindari M, Samonis G. Insights into Pathogenesis of Trachoma. Microorganisms 2024; 12:1544. [PMID: 39203386 PMCID: PMC11355952 DOI: 10.3390/microorganisms12081544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 05/31/2024] [Accepted: 07/25/2024] [Indexed: 09/03/2024] Open
Abstract
Trachoma is the most common infectious cause of blindness worldwide. This review investigates the pathogenesis of trachoma, focusing on its causative agent, transmission pathways, disease progression, and immune responses. Trachoma is caused by serovars A-C of the bacterium Chlamydia trachomatis (Ct). Transmission occurs through direct or indirect exchanges of ocular and nasal secretions, especially in regions with poor hygiene and overcrowded living conditions. The disease is initiated in early childhood by repeated infection of the ocular surface by Ct. This triggers recurrent chronic inflammatory episodes, leading to the development of conjunctival scarring and potentially to trichiasis, corneal opacity, and visual impairment. Exploring the pathogenesis of trachoma not only unveils the intricate pathways and mechanisms underlying this devastating eye disease but also underscores the multifaceted dimensions that must be considered in its management.
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Affiliation(s)
- Panagiotis Toumasis
- MSc in Ocular Surgery, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (P.T.); (I.T.T.); (M.E.)
| | - Georgia Vrioni
- Department of Microbiology, School of Medicine, National and Kapodistrian University of Athens, 115 25 Athens, Greece;
| | - Ioannis T. Tsinopoulos
- MSc in Ocular Surgery, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (P.T.); (I.T.T.); (M.E.)
- Second Department of Ophthalmology, School of Medicine, Aristotle University of Thessaloniki, Papageorgiou General Hospital, 564 29 Thessaloniki, Greece
| | - Maria Exindari
- MSc in Ocular Surgery, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece; (P.T.); (I.T.T.); (M.E.)
- Department of Microbiology, School of Medicine, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | - George Samonis
- School of Medicine, University of Crete, 715 00 Heraklion, Greece
- Metropolitan Hospital, 185 47 Piraeus, Greece
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Shu’aibu J, Ajege G, Mpyet C, Dejene M, Isiyaku S, Tafida A, Kelly M, Emereuwa I, Courtright P. Optimizing Trichiasis Case Finding to Attain the Elimination of Trachoma as a Public Health Problem. Trop Med Infect Dis 2024; 9:157. [PMID: 39058199 PMCID: PMC11281651 DOI: 10.3390/tropicalmed9070157] [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: 05/08/2024] [Revised: 07/04/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND As national trachoma programmes increase efforts to reduce the burden of trachomatous trichiasis (TT), TT case finding and referral are critical public health programme components. Our research aimed to explore the most effective and efficient approaches to finding, referring, and managing TT cases. METHODS This was a prospective descriptive study, utilizing both routine programme data and primary data collection. This study compared four different approaches to finding TT cases across three different local government areas (LGAs) in Kano State, Nigeria. Each of the study LGAs was divided into four sub-units to accommodate the four different approaches. RESULTS The number of outreach attendees was 4795 across the four case finding approaches, and this varied hugely, with the smallest number and proportion (403, 0.26%) in settings only employing house-to-house case finding and the largest number and proportion (1901, 0.99%) when town criers were used. That said, the proportion of TT cases among people presenting at outreach was highest (32.5%) when house-to-house case finding was used and lowest (10.3%) when town criers were used. More female TT patients were found (53-70%) and had surgery (79-85%) compared to male cases, across all approaches. The average project expenditure for finding one TT case was similar for approaches that included house-to-house case finding (USD 5.4-6.3), while it was 3.5 times higher (USD 21.5 per TT case found) when town criers were used. DISCUSSION This study found that the house-to-house TT case finding approaches were the most efficient method with the highest yield of TT cases. Including other eye condition and/or vision testing yielded similar results but required more personnel and cost.
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Affiliation(s)
- Joy Shu’aibu
- Sightsavers, Abuja 900231, Nigeria
- Department of Family Medicine, Bingham University, Karu 961105, Nigeria
| | | | - Caleb Mpyet
- Sightsavers, Abuja 900231, Nigeria
- Department of Ophthalmology, University of Jos, Jos 930003, Nigeria
| | - Michael Dejene
- Public Health Consultancy Services, Addis Ababa 1169, Ethiopia
| | | | | | | | | | - Paul Courtright
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town 7925, South Africa
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Srivathsan A, Abdou A, Al-Khatib T, Apadinuwe SC, Badiane MD, Bucumi V, Chisenga T, Kabona G, Kabore M, Kanyi SK, Bella L, M’po N, Masika M, Minnih A, Sitoe HM, Mishra S, Olobio N, Omar FJ, Phiri I, Sanha S, Seife F, Sharma S, Tekeraoi R, Traore L, Watitu T, Bol YY, Borlase A, Deiner MS, Renneker KK, Hooper PJ, Emerson PM, Vasconcelos A, Arnold BF, Porco TC, Hollingsworth TD, Lietman TM, Blumberg S. District-Level Forecast of Achieving Trachoma Elimination as a Public Health Problem By 2030: An Ensemble Modelling Approach. Clin Infect Dis 2024; 78:S101-S107. [PMID: 38662700 PMCID: PMC11045026 DOI: 10.1093/cid/ciae031] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2024] Open
Abstract
Assessing the feasibility of 2030 as a target date for global elimination of trachoma, and identification of districts that may require enhanced treatment to meet World Health Organization (WHO) elimination criteria by this date are key challenges in operational planning for trachoma programmes. Here we address these challenges by prospectively evaluating forecasting models of trachomatous inflammation-follicular (TF) prevalence, leveraging ensemble-based approaches. Seven candidate probabilistic models were developed to forecast district-wise TF prevalence in 11 760 districts, trained using district-level data on the population prevalence of TF in children aged 1-9 years from 2004 to 2022. Geographical location, history of mass drug administration treatment, and previously measured prevalence data were included in these models as key predictors. The best-performing models were included in an ensemble, using weights derived from their relative likelihood scores. To incorporate the inherent stochasticity of disease transmission and challenges of population-level surveillance, we forecasted probability distributions for the TF prevalence in each geographic district, rather than predicting a single value. Based on our probabilistic forecasts, 1.46% (95% confidence interval [CI]: 1.43-1.48%) of all districts in trachoma-endemic countries, equivalent to 172 districts, will exceed the 5% TF control threshold in 2030 with the current interventions. Global elimination of trachoma as a public health problem by 2030 may require enhanced intervention and/or surveillance of high-risk districts.
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Affiliation(s)
- Ariktha Srivathsan
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Amza Abdou
- Programme National de Santé Oculaire, Ministère De La Santé Publique, Niamey, Niger
| | - Tawfik Al-Khatib
- Prevention of Blindness Program, Ministry of Public Health & Population, Sana'a, Yemen
| | | | - Mouctar D Badiane
- Programme National de Promotion de La Santé Oculaire, Ministère de la Santé et de L'Action sociale, Dakar, Sénégal
| | - Victor Bucumi
- Département En Charge des Maladies Tropicales Négligées, Ministère De La Santé Publique Et De La Lutte Contre Le Sida, Bujumbura, Burundi
| | - Tina Chisenga
- Ministry of Health Public Health Department, Lusaka, Zambia
| | - George Kabona
- Neglected Tropical Disease Control Program, Ministry of Health and Social Welfare, Dar Es Salaam, United Republic of Tanzania
| | - Martin Kabore
- Programme national de lutte contre les maladies tropicales négligées, Ministère de la santé et de l'hygiène publique, Ouagadougou, Burkina Faso
| | - Sarjo Kebba Kanyi
- The National Eye Health Programme, Ministry of Health and Social Welfare, Banjul, Kanifing, The Gambia
| | - Lucienne Bella
- Programme National De Lutte Contre La Cécité, Ministère De La Santé Publique, Yaoundé, Cameroon
| | - Nekoua M’po
- Programme National De Lutte Contre Les Maladies Transmissibles, Ministère De La Santé, Cotonou, Benin
| | - Michael Masika
- Department of Clinical Services, Ministry of Health, Lilongwe, Malawi
| | - Abdellahi Minnih
- Département Des Maladies Transmissibles, Ministère De La Santé Nouakchott, Nouakchott, Mauritania
| | - Henis Mior Sitoe
- Direcção Nacional De Saúde Pública Ministerio Da Saude, Maputo, Mozambique
| | | | - Nicholas Olobio
- National Trachoma Elimination Programme, Federal Ministry of Health, Abuja, Nigeria
| | | | - Isaac Phiri
- Department of Epidemiology and Disease Control, Ministry of Health & Child Welfare, Harare, Zimbabwe
| | - Salimato Sanha
- Programa Nacional De Saúde De Visão, Minsap, Bissau, Guinea-Bissau
| | - Fikre Seife
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Rabebe Tekeraoi
- Eye Department, Ministry of Health and Medical Services, South Tarawa, Kiribati
| | - Lamine Traore
- Programme National de la Santé Oculaire, Ministère de la Santé, Bamako, Mali
| | | | - Yak Yak Bol
- Neglected Tropical Diseases Programme, Ministry of Health, Juba, South Sudan
| | - Anna Borlase
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | - Michael S Deiner
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Kristen K Renneker
- International Trachoma Initiative, The Task Force for Global Health, Decatur, Georgia, USA
| | - P J Hooper
- International Trachoma Initiative, The Task Force for Global Health, Decatur, Georgia, USA
| | - Paul M Emerson
- International Trachoma Initiative, The Task Force for Global Health, Decatur, Georgia, USA
| | - Andreia Vasconcelos
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, United Kingdom
| | - Benjamin F Arnold
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Travis C Porco
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - T Déirdre Hollingsworth
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, United Kingdom
| | - Thomas M Lietman
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Seth Blumberg
- Francis I. Proctor Foundation, University of California, San Francisco, California, USA
- Department of Medicine, University of California, San Francisco, California, USA
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Gomez DVF, de Almeida WDS, de Souza Junior PRB, Lopes MDFC, Luna EJDA, Zimmermann IR, Tavares NUL, Gutierrez MMU, Szwarcwald CL. Prevalence of trachoma in indigenous and non-indigenous areas, Northeastern Brazil, 2019-2021. Rev Panam Salud Publica 2024; 48:e19. [PMID: 38464869 PMCID: PMC10924615 DOI: 10.26633/rpsp.2024.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 01/08/2024] [Indexed: 03/12/2024] Open
Abstract
Objective To estimate the prevalence of trachoma in indigenous and non-indigenous populations in selected areas of the state of Maranhão, in northeastern Brazil. Methods This was a population-based survey with probabilistic sampling. For the diagnosis of trachoma, external ocular examination was performed using head magnifying loupes, at 2.5X magnification. The prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years and the prevalence of trachomatous trichiasis (TT) in the population aged ≥15 years were estimated. Relative frequencies of sociodemographic and environmental characteristics were obtained. Results The study included 7 971 individuals, 3 429 from non-indigenous populations and 4 542 from indigenous populations. The prevalence of TF in non-indigenous and indigenous populations was 0.1% and 2.9%, respectively, and the prevalence of TT among indigenous populations was 0.1%. Conclusions The prevalence of TF and TT in the two evaluation units in the state of Maranhão were within the limits recommended for the elimination of trachoma as a public health problem. However, the prevalence of TF was higher in the indigenous evaluation unit, indicating a greater vulnerability of this population to the disease. The prevalence of TF of below 5.0% implies a reduction in transmission, which may have resulted from improved socioeconomic conditions and/or the implementation of the World Health Organization SAFE strategy.
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Olamiju F, Isiyaku S, Olobio N, Mogaji H, Achu I, Muhammad N, Boyd S, Bakhtiari A, Ebenezer A, Jimenez C, Solomon AW, Harding-Esch EM, Mpyet CD. Prevalence of Trachoma following Implementation of the SAFE Strategy in Three Local Government Areas of Taraba State, North Eastern Nigeria. Ophthalmic Epidemiol 2023; 30:619-627. [PMID: 35353025 DOI: 10.1080/09286586.2022.2045025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 02/10/2022] [Indexed: 10/18/2022]
Abstract
INTRODUCTION In 2019-2020, one round of antibiotic mass drug administration (MDA) was implemented for trachoma elimination purposes in Donga, Gashaka, and Ussa local government areas (LGAs) of Taraba State, Nigeria, following baseline surveys in 2009 (Donga and Gashaka) and 2013-2014 (Ussa). Here, trachoma prevalence post-MDA in these three LGAs is reported. METHODS In 2019 (Gashaka and Ussa) and 2020 (Donga), population-based, cross-sectional surveys were conducted following World Health Organization (WHO) guidance. A two-stage cluster sampling strategy was used. All residents of selected households aged ≥1 year were examined by Tropical Data-certified graders for trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT) using the WHO simplified trachoma grading scheme. Data on water, sanitation, and hygiene (WASH) access were also collected. RESULTS A total of 1,883 households participated. From these households, 4,885 children aged 1-9 years were enumerated, and 4,866 (99.6%) examined. There were 5,050 eligible adults (aged ≥15 years) enumerated in the same households, of whom 4,888 (96.8%) were examined. Age-adjusted TF prevalence in children aged 1-9 years was 0.22% (95% CI: 0.00-0.65) in Donga, 0.0% in Gashaka, and 0.19% (95% CI: 0.00-0.44) in Ussa. The age- and gender-adjusted TT prevalence unknown to the health system in adults aged ≥15 years was 0.08% (95% CI: 0.00-0.19) in Donga, 0.02% (95% CI: 0.00-0.06) in Gashaka, and 0.10% (95% CI: 0.01-0.18) in Ussa. In Donga, Gashaka, and Ussa, respectively, 66%, 49% and 63% of households had access to an improved drinking water source, and 68%, 56% and 29% had access to an improved latrine. CONCLUSION In all LGAs, the elimination thresholds for TF and TT unknown to the health system have been attained in the target age groups. These LGAs should be re-surveyed after 2 years to show that reductions in TF prevalence have been sustained in the absence of MDA. Health authorities should continue to improve WASH facilities to reduce the risk of later recrudescence.
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Affiliation(s)
| | | | | | - Hammed Mogaji
- Department of Animal and Environmental Biology, Federal University Oye-Ekiti, Ekiti, Nigeria
| | - Ijeoma Achu
- Mission To Save The Helpless (MITOSATH), Jos, Nigeria
| | - Nasiru Muhammad
- Ophthalmology Department, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Sarah Boyd
- International Trachoma Initiative, Task Force for Global Health, Decatur, Georgia, USA
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Decatur, Georgia, USA
| | | | | | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Emma M Harding-Esch
- London Centre for Neglected Tropical Disease Research, London, UK
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Caleb D Mpyet
- Sightsavers, Nigeria Country Office, Kaduna, Nigeria
- Department of Ophthalmology, College of Health Sciences, University of Jos, Jos, Nigeria
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Salam AS, Qayumi R, Majeed Siddiqi A, Naseem M, Mansoor M, Butcher R, Bakhtiari A, Renneker K, Willis R, Jimenez C, Dejene M, Safi N, Heggen A, Solomon AW, Harding-Esch EM, Alizoi N. Prevalence of Trachoma in 72 Districts of Afghanistan in 2018-2019: Results of 35 Population-based Prevalence Surveys. Ophthalmic Epidemiol 2023; 30:608-618. [PMID: 35272540 PMCID: PMC10581673 DOI: 10.1080/09286586.2021.2015784] [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: 03/08/2021] [Revised: 10/16/2021] [Accepted: 12/05/2021] [Indexed: 10/18/2022]
Abstract
BACKGROUND To determine where interventions are needed to eliminate trachoma as a public health problem, prevalence data are needed. We aimed to generate baseline population-based data on trachoma prevalence in suspected-endemic areas of Afghanistan. METHODS Cross-sectional population-based prevalence surveys designed according to World Health Organization (WHO) recommendations were conducted in 35 evaluation units (EUs) covering 72 districts. In selected households, all resident individuals aged ≥1 year were examined for trachomatous inflammation-follicular (TF) and trachomatous trichiasis (TT) according to the WHO simplified trachoma grading system. Water, sanitation and hygiene access was assessed in households of survey participants. RESULTS 104,104 people aged ≥1 year were examined, including 43,774 children aged 1-9 years and 46,439 people aged ≥15 years. The age-adjusted prevalence of TF in 1-9-year-olds was ≥5% in 3 EUs, with the highest EU TF prevalence being 7.8%. The age- and gender-adjusted prevalence of TT unknown to the health system in ≥15-year-olds was <0.2% in all EUs. The majority of households had access to an improved water source within 30 minutes of the house. However, only a minority of households had an improved latrine and/or a handwash station. CONCLUSIONS Trachoma is not a public health problem in the majority of EUs surveyed. However, antibiotic mass drug administration, promotion of facial cleanliness and environmental improvement (the A, F and E components of the SAFE strategy) are needed for trachoma elimination purposes in three of the EUs surveyed in Afghanistan.
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Affiliation(s)
| | | | | | | | | | - Robert Butcher
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | | | | | | | | | | | - Naimullah Safi
- Afghanistan Country Office, World Health Organization, Kabul, Afghanistan
| | | | - 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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8
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Ilako D, Barasa E, Gichangi M, Mwatha S, Watitu T, Bore J, Rajamani A, Butcher R, Flueckiger RM, Bakhtiari A, Willis R, Solomon AW, Harding-Esch EM, Matendechero SH. Prevalence of Trachomatous Trichiasis in Ten Evaluation Units of Embu and Kitui Counties, Kenya. Ophthalmic Epidemiol 2023; 30:591-598. [PMID: 35037814 PMCID: PMC10581664 DOI: 10.1080/09286586.2021.1986549] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 08/24/2021] [Accepted: 09/22/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Late-stage blinding sequalae of trachoma such as trachomatous trichiasis (TT) typically take decades to develop and often do so in the absence of ongoing ocular Chlamydia trachomatis infection. This suggests that most TT risk accumulates in early life; as a result, population-level TT incidence and prevalence can remain high years after C. trachomatis transmission among children has decreased. In Embu and Kitui counties, Kenya, the prevalence of trachomatous inflammation - follicular is low in children. In this survey, we set out to determine the prevalence of TT in ten evaluation units (EUs) in these counties. METHODS We undertook ten cross-sectional prevalence surveys for TT. In each EU, people aged ≥15 years were selected by a two-stage cluster sampling method and examined for TT. Those with TT were asked questions on whether they had been offered management for it. Prevalence was adjusted to the underlying age and gender structure of the population. RESULTS A total of 18,987 people aged ≥15 years were examined. Per EU, the median number of examined participants was 1,656 (range: 1,451 - 3,016) and median response rate was 86% (range: 81 - 95%). The prevalence of TT unknown to the health system in people aged ≥15 years was above the threshold for elimination (≥0.2%) in all ten EUs studied (range: 0.2-0.7%). TT was significantly more common in older than younger individuals and in women than in men. DISCUSSION Provision of surgical services should be strengthened in Embu and Kitui counties of Kenya to achieve the World Health Organization threshold for eliminating TT as a public health problem.
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Affiliation(s)
- D Ilako
- Department of Ophthalmology, University of Nairobi, Nairobi, Kenya
| | - E Barasa
- Ophthalmic Services Unit, Ministry of Health, Nairobi, Kenya
| | - M Gichangi
- Ophthalmic Services Unit, Ministry of Health, Nairobi, Kenya
| | - S Mwatha
- Neglected Tropical Diseases Unit, Ministry of Health, Nairobi, Kenya
| | - T Watitu
- Neglected Tropical Diseases Unit, Ministry of Health, Nairobi, Kenya
| | - J Bore
- Kenya National Bureau of Statistics, Ministry of Planning, Nairobi, Kenya
| | - A Rajamani
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - R Butcher
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | | | - A Bakhtiari
- Task Force for Global Health, Atlanta, GA, USA
| | - R Willis
- Task Force for Global Health, Atlanta, GA, USA
| | - AW Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - EM Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - SH Matendechero
- Neglected Tropical Diseases Unit, Ministry of Health, Nairobi, Kenya
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9
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Seyum D, Fetene N, Kifle T, Negash H, Kabeto T, Gebre M, Data T, Tadele T, Abayo G, Wondimu A, Butcher R, Bakhtiari A, Willis R, Boyd S, Jimenez C, Negussu N, Tadesse F, Kebede F, Dejene M, Solomon AW, Harding-Esch EM, Sisay A. Prevalence of Trachoma from 66 Impact Surveys in 52 Woredas of Southern Nations, Nationalities and Peoples' and Sidama Regions of Ethiopia, 2017-2019. Ophthalmic Epidemiol 2023; 30:637-646. [PMID: 35473569 PMCID: PMC10581674 DOI: 10.1080/09286586.2022.2065313] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 04/01/2022] [Accepted: 04/07/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE Trachoma is endemic in Southern Nations, Nationalities and Peoples' (SNNP) and Sidama regions of Ethiopia. We aimed to measure the prevalence of trachomatous inflammation-follicular (TF) among children aged 1 - 9 years and the prevalence of trachomatous trichiasis (TT) unknown to the health system among people aged ≥15 years following interventions for trachoma in 52 woredas of SNNP and Sidama regions. METHODS From 2017 - 2019, 66 two-stage cluster sampling cross-sectional population-based surveys were carried out in 52 woredas (third-level administrative divisions) using a standardized World Health Organization-recommended survey methodology. This included one impact survey in 40 woredas, two consecutive impact surveys in 10 woredas and three consecutive impact surveys in two woredas. Water, sanitation and Hygiene (WASH) access was assessed using a modified version of the United Nations Children's Fund/WHO Joint Monitoring Programme questionnaire. RESULTS By the end of this survey series, 15 (23%) of the woredas had met the active trachoma elimination threshold (TF prevalence <5%) and 12 (18%) had met the TT threshold (TT ≤ 0.2%). Regarding WASH coverage, 20% of households had access to an improved drinking water source within a 30-min journey and 3% had an improved latrine. There was strong evidence that TF was less common in 4 - 6-year-olds and 7 - 9-year-olds than 1 - 3-year-olds. CONCLUSION Based on the findings, further antibiotic mass drug administration is required in 37 woredas and active TT case finding is needed in 40 woredas. In these surveys, access to WASH facilities was very low; WASH improvements are required.
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Affiliation(s)
- Dawit Seyum
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - N Fetene
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Tezera Kifle
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Habtamu Negash
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Temesgen Kabeto
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Mulatu Gebre
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Tadesse Data
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
| | - Tafese Tadele
- Southern Nations, Nationalities and Peoples’ Regional Health Bureau, Hawassa, Ethiopia
| | | | | | | | - Ana Bakhtiari
- ITI, Task Force for Global Health, Decatur, GEORGIA, USA
| | - Rebecca Willis
- ITI, Task Force for Global Health, Decatur, GEORGIA, USA
| | - Sarah Boyd
- ITI, Task Force for Global Health, Decatur, GEORGIA, USA
| | | | - Nebiyu Negussu
- Ministry of Health, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Fentahun Tadesse
- Ministry of Health, Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Fikreab Kebede
- Ministry of Health, Federal Ministry of Health, 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
| | - Alemayehu Sisay
- Orbis International Ethiopia, Orbis International Ethiopia, Addis Ababa, Ethiopia
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10
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Szwarcwald CL, Lopes MDFC, Borges de Souza Junior PR, Vaz Ferreira Gómez D, Luna EJDA, da Silva de Almeida W, Damacena GN, Ribeiro Favacho JDF, Germano de Frias P, Butcher R, Boyd S, Bakhtiari A, Willis R, Jimenez C, Harding-Esch E, Saboyá-Díaz MI, Solomon AW. Population Prevalence of Trachoma in Nine Rural Non-Indigenous Evaluation Units of Brazil. Ophthalmic Epidemiol 2023; 30:561-570. [PMID: 34711133 PMCID: PMC10581672 DOI: 10.1080/09286586.2021.1941127] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 05/20/2021] [Accepted: 06/04/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE To assess the contemporary prevalence of trachoma in Brazil's non-indigenous population, surveys of those thought to be at greatest risk of disease were conducted. METHODS Rural census tracts of non-indigenous population from nine mesoregions were selected to compose the survey evaluation units (EUs) by considering previously endemic municipalities at greatest risk of trachoma. In each of the nine EUs, we conducted a population-based prevalence survey. Every resident of selected households aged ≥ 1 year was examined for trachomatous inflammation - follicular (TF) and trachomatous trichiasis (TT). Additionally, data were collected on household-level access to water, sanitation, hygiene (WASH) and education. RESULTS A total of 27,962 individuals were examined across nine EUs. The age-adjusted TF prevalence in 1-9-year-olds was <5% in each EU. The age- and gender-adjusted prevalence of TT unknown to the health system in ≥15-year-olds was <0.2% in eight EUs; in one EU, it was 0.22%. The median number of households surveyed per EU with access to an improved drinking water source within a 30-minute roundtrip of the house was 66%. School attendance was >99% of surveyed children. CONCLUSIONS The prevalence of TF was well below the target for elimination as a public health problem in all EUs. Because EUs surveyed were selected to represent the highest-risk non-indigenous areas of the country, TF prevalence is unlikely to be ≥5% in non-indigenous populations elsewhere. In one EU, the prevalence of TT was above the target threshold for elimination. Further investigation and possibly improvement in TT surgical provision are required in that EU.
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Affiliation(s)
- Célia Landmann Szwarcwald
- Institute of Scientific and Technological Communication and Information in Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Maria de Fátima Costa Lopes
- Coordination of Surveillance of Zoonoses and Vector Transmission Diseases, Department of Immunization and Communicable Diseases, Health Surveillance Secretariat, Ministry of Health, Brasília, Brazil
| | | | - Daniela Vaz Ferreira Gómez
- Coordination of Surveillance of Zoonoses and Vector Transmission Diseases, Department of Immunization and Communicable Diseases, Health Surveillance Secretariat, Ministry of Health, Brasília, Brazil
| | | | - Wanessa da Silva de Almeida
- Institute of Scientific and Technological Communication and Information in Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Giseli Nogueira Damacena
- Institute of Scientific and Technological Communication and Information in Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | | | - Paulo Germano de Frias
- Board of Education and Research, Study Group on Health Assessment and Management, Professor Fernando Figueira Integral Medicine Institute (IMIP), Recife, Brazil
| | - Robert Butcher
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Sarah Boyd
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | - Rebecca Willis
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | | | - Emma Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Martha Idalí Saboyá-Díaz
- Neglected, Tropical, and Vector-Borne Diseases Unit, Communicable Diseases and Environmental Determinants of Health Department, Pan American Health Organization (PAHO), Washington, DC, USA
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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11
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Harding-Esch EM, Burgert-Brucker CR, Jimenez C, Bakhtiari A, Willis R, Dejene Bejiga M, Mpyet C, Ngondi J, Boyd S, Abdala M, Abdou A, Adamu Y, Alemayehu A, Alemayehu W, Al-Khatib T, Apadinuwe SC, Awaca N, Awoussi MS, Baayendag G, Badiane Mouctar D, Bailey RL, Batcho W, Bay Z, Bella A, Beido N, Bol YY, Bougouma C, Brady CJ, Bucumi V, Butcher R, Cakacaka R, Cama A, Camara M, Cassama E, Chaora SG, Chebbi AC, Chisambi AB, Chu B, Conteh A, Coulibaly SM, Courtright P, Dalmar A, Dat TM, Davids T, DJAKER MEA, de Fátima Costa Lopes M, Dézoumbé D, Dodson S, Downs P, Eckman S, Elshafie BE, Elmezoghi M, Elvis AA, Emerson P, Epée EEE, Faktaufon D, Fall M, Fassinou A, Fleming F, Flueckiger R, Gamael KK, Garae M, Garap J, Gass K, Gebru G, Gichangi MM, Giorgi E, Goépogui A, Gómez DVF, Gómez Forero DP, Gower EW, Harte A, Henry R, Honorio-Morales HA, Ilako DR, Issifou AAB, Jones E, Kabona G, Kabore M, Kadri B, Kalua K, Kanyi SK, Kebede S, Kebede F, Keenan JD, Kello AB, Khan AA, KHELIFI H, Kilangalanga J, KIM SH, Ko R, Lewallen S, Lietman T, Logora MSY, Lopez YA, MacArthur C, Macleod C, Makangila F, Mariko B, Martin DL, Masika M, Massae P, Massangaie M, Matendechero HS, Mathewos T, McCullagh S, Meite A, Mendes EP, Abdi HM, Miller H, Minnih A, Mishra SK, Molefi T, Mosher A, M’Po N, Mugume F, Mukwiza R, Mwale C, Mwatha S, Mwingira U, Nash SD, NASSA C, Negussu N, Nieba C, Noah Noah JC, Nwosu CO, Olobio N, Opon R, Pavluck A, Phiri I, Rainima-Qaniuci M, Renneker KK, Saboyá-Díaz MI, Sakho F, Sanha S, Sarah V, Sarr B, Szwarcwald CL, Shah Salam A, Sharma S, Seife F, Serrano Chavez GM, Sissoko M, Sitoe HM, Sokana O, Tadesse F, Taleo F, Talero SL, Tarfani Y, Tefera A, Tekeraoi R, Tesfazion A, Traina A, Traoré L, Trujillo-Trujillo J, Tukahebwa EM, Vashist P, Wanyama EB, WARUSAVITHANA SD, Watitu TK, West S, Win Y, Woods G, YAJIMA A, Yaya G, Zecarias A, Zewengiel S, Zoumanigui A, Hooper PJ, Millar T, Rotondo L, Solomon AW. Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys. Ophthalmic Epidemiol 2023; 30:544-560. [PMID: 38085791 PMCID: PMC10751062 DOI: 10.1080/09286586.2023.2249546] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 08/11/2023] [Indexed: 12/18/2023]
Abstract
PURPOSE Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys. METHODS Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported. RESULTS Between 29th February 2016 and 24th April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma. CONCLUSION This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Amza Abdou
- Programme National de Santé Oculaire, Niger
| | | | | | | | | | | | - Naomie Awaca
- Ministère de la Santé Publique, Democratic Republic of Congo
| | | | | | | | | | | | | | | | | | | | - Clarisse Bougouma
- Programme national de lutte contre les maladies tropicales négligées (PNMTN), Burkina Faso
| | | | - Victor Bucumi
- National Integrated Programme for the Control of Neglected Tropical Diseases and Blindness (PNIMTNC), Burundi
| | | | | | | | | | | | | | | | | | - Brian Chu
- International Trachoma Initiative, USA
| | | | | | - Paul Courtright
- Division of Ophthalmology, University of Cape Town, Cape Town, South Africa, South Africa
| | - Abdi Dalmar
- Ministry of Human Development and Public Services, Somalia
| | | | | | | | | | | | | | | | | | | | | | - Ange Aba Elvis
- Programme National de la Santé Oculaire et de la lutte contre l’Onchocercose, Côte d’Ivoire
| | | | | | | | | | | | | | | | | | | | - Jambi Garap
- Port Moresby General Hospital, Papua New Guinea
| | | | | | | | | | | | | | | | | | - Anna Harte
- London School of Hygiene & Tropical Medicine, UK
| | - Rob Henry
- U.S. Agency for International Development, USA
| | | | | | | | | | | | - Martin Kabore
- Programme national de lutte contre les maladies tropicales négligées (PNMTN), Burkina Faso
| | | | - Khumbo Kalua
- Blantyre Institute for Community Outreach, Malawi
| | | | | | | | | | | | | | | | | | | | - Robert Ko
- Port Moresby General Hospital, Papua New Guinea
| | - Susan Lewallen
- Division of Ophthalmology, University of Cape Town, Cape Town, South Africa, South Africa
| | | | | | - Yuri A Lopez
- SACAICET / MINISTERIO DEL PODER POPULAR PARA LA SALUD, Venezuela
| | | | | | | | | | | | | | | | | | | | | | | | - Aboulaye Meite
- Ministère de la Santé et de l’Hygiène Publique, Cote d’Ivoire
| | | | | | | | | | | | | | - Aryc Mosher
- U.S. Agency for International Development, USA
| | | | | | | | | | | | | | | | | | | | - Cece Nieba
- Ministère de la Santé et de l’Hygiene Publique, Guinea
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Oliver Sokana
- Solomon Islands Ministry of Health and Medical Services, Solomon Islands
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12
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Adimassu NF, Assem AS, Fekadu SA. Postoperative trachomatous trichiasis: a systematic review and meta-analysis study. Int Health 2023; 15:623-629. [PMID: 36852770 PMCID: PMC10629961 DOI: 10.1093/inthealth/ihad014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/04/2023] [Accepted: 02/10/2023] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND Trachomatous trichiasis is the potential stage of trachoma in which the eyelashes scratch the surface of the globe, ultimately causing corneal opacity, visual impairment and blindness. The aim of this systematic review and meta-analysis is to obtain the pooled prevalence and associated factors of postoperative trachomatous trichiasis (PTT) in World Health Organization (WHO) trachoma-endemic regions. METHODS An inclusive literature search was undertaken using PubMed, Cochrane Library, Science Direct and Google Scholar databases from 30 May 2022 to 28 June 2022. I2 statistics and funnel plots were used to determine heterogeneity and publication bias among included studies. A random effects model was used to estimate pooled prevalence, incidence and odds ratios (ORs) with the respective 95% confidence intervals (CIs) using RevMan 5.4 software. RESULTS Eighteen articles were included in this meta-analysis and systematic review. The pooled prevalence of PTT was 19% (range 18-21). PTT was lower among young adults compared with old adults (OR 0.63 [95% CI 0.44 to 0.92]), single-dose oral azithromycin as compared with tetracycline eye ointment users (OR 0.82 [95% CI 0.69 to 0.99]) and minor trichiasis before surgery as compared with major trichiasis (OR 0.63 [95% CI 0.47 to 0.85]). CONCLUSIONS The incidence of PTT was higher than the WHO's recommendation. Prescribing single-dose oral azithromycin after surgery, periodic training for trichiasis surgeons, close follow-up and health education after surgery are crucial to minimize the recurrence.Study protocol registration on PROSPERO: CRD42022336003.
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Affiliation(s)
- Nebiyat Feleke Adimassu
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Abel Sinshaw Assem
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Sofonias Addis Fekadu
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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13
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Borlase A, Prada JM, Crellen T. Modelling morbidity for neglected tropical diseases: the long and winding road from cumulative exposure to long-term pathology. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220279. [PMID: 37598702 PMCID: PMC10440174 DOI: 10.1098/rstb.2022.0279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 07/13/2023] [Indexed: 08/22/2023] Open
Abstract
Reducing the morbidities caused by neglected tropical diseases (NTDs) is a central aim of ongoing disease control programmes. The broad spectrum of pathogens under the umbrella of NTDs lead to a range of negative health outcomes, from malnutrition and anaemia to organ failure, blindness and carcinogenesis. For some NTDs, the most severe clinical manifestations develop over many years of chronic or repeated infection. For these diseases, the association between infection and risk of long-term pathology is generally complex, and the impact of multiple interacting factors, such as age, co-morbidities and host immune response, is often poorly quantified. Mathematical modelling has been used for many years to gain insights into the complex processes underlying the transmission dynamics of infectious diseases; however, long-term morbidities associated with chronic or cumulative exposure are generally not incorporated into dynamic models for NTDs. Here we consider the complexities and challenges for determining the relationship between cumulative pathogen exposure and morbidity at the individual and population levels, drawing on case studies for trachoma, schistosomiasis and foodborne trematodiasis. We explore potential frameworks for explicitly incorporating long-term morbidity into NTD transmission models, and consider the insights such frameworks may bring in terms of policy-relevant projections for the elimination era. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.
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Affiliation(s)
- Anna Borlase
- Department of Biology, University of Oxford, Oxford OX1 3SZ, UK
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, UK
| | - Joaquin M. Prada
- Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Thomas Crellen
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, UK
- School of Biodiversity, One Health & Veterinary Medicine, Graham Kerr Building, University of Glasgow, Glasgow G12 8QQ, UK
- Wellcome Centre for Integrative Parasitology, Sir Graeme Davies Building, University of Glasgow, Glasgow G12 8TA, UK
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14
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Kanyi S, Hydara A, Sillah A, Mpyet C, Harte A, Bakhtiari A, Willis R, Jimenez C, Aboe A, Bailey R, Harding-Esch EM, Solomon AW, Joof BM. The Gambia Trachomatous Trichiasis Surveys: Results from Five Evaluation Units Confirm Attainment of Trachoma Elimination Thresholds. Ophthalmic Epidemiol 2023:1-9. [PMID: 37401113 DOI: 10.1080/09286586.2023.2213320] [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: 09/26/2022] [Revised: 04/12/2023] [Accepted: 05/09/2023] [Indexed: 07/05/2023]
Abstract
INTRODUCTION Trichiasis is present when in-turned eyelashes touch the eyeball. It may result in permanent vision loss. Trachomatous trichiasis (TT) is caused by multiple rounds of inflammation associated with conjunctival Chlamydia trachomatis infection. Surveys have been designed to estimate the prevalence of TT in evaluation units (EUs) of trachoma-endemic countries in order to help develop appropriate programme-level plans. In this study, TT-only surveys were conducted in five EUs of The Gambia to determine whether further intensive programmatic action was required. METHODS Two-stage cluster sampling was used to select 27 villages per EU and ~25 households per village. Graders assessed the TT status of individuals aged ≥15 years in each selected household, including the presence or absence of conjunctival scarring in those with TT. RESULTS From February to March 2019, 11595 people aged ≥15 years were examined. A total of 34 cases of TT were identified. All five EUs had an age- and gender-adjusted prevalence of TT unknown to the health system <0.2%. Three of five EUs had a prevalence of 0.0%. CONCLUSION Using these and other previously collected data, in 2021, The Gambia was validated as having achieved national elimination of trachoma as a public health problem. Trachoma is still present in the population, but as its prevalence is low, it is unlikely that today's youth will experience the exposure to C. trachomatis required to precipitate TT. The Gambia demonstrates that with political will and consistent application of human and financial resources, trachoma can be eliminated as a public health problem.
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Affiliation(s)
- Sarjo Kanyi
- The National Eye Health Programme, Ministry of Health, Banjul, Kanifing, The Gambia
| | - Abba Hydara
- Sheikh Zayed Regional Eye Care Center, Banjul, Kanifing, The Gambia
| | - Ansumana Sillah
- The National Eye Health Programme, Ministry of Health, Banjul, Kanifing, The Gambia
| | - Caleb Mpyet
- Department of Ophthalmology, University of Jos, Jos, Nigeria
- Sightsavers Nigeria Country Office, Kaduna, Nigeria
| | - Anna Harte
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | - Rebecca Willis
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | | | - Agatha Aboe
- Department of Ophthalmology, University of Jos, Jos, Nigeria
| | - Robin Bailey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Emma M Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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15
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Goodhew EB, Taoaba R, Harding-Esch EM, Gwyn SE, Bakhtiari A, Butcher R, Cama A, Guagliardo SAJ, Jimenez C, Mpyet CD, Tun K, Wickens K, Solomon AW, Martin DL, Tekeraoi R. Changes in trachoma indicators in Kiribati with two rounds of azithromycin mass drug administration, measured in serial population-based surveys. PLoS Negl Trop Dis 2023; 17:e0011441. [PMID: 37418501 PMCID: PMC10355439 DOI: 10.1371/journal.pntd.0011441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 07/19/2023] [Accepted: 06/06/2023] [Indexed: 07/09/2023] Open
Abstract
Baseline mapping in the two major population centers of Kiribati showed that trachoma was a public health problem in need of programmatic interventions. After conducting two annual rounds of antibiotic mass drug administration (MDA), Kiribati undertook trachoma impact surveys in 2019, using standardized two-stage cluster surveys in the evaluation units of Kiritimati Island and Tarawa. In Kiritimati, 516 households were visited and in Tarawa, 772 households were visited. Nearly all households had a drinking water source and access to an improved latrine. The prevalence of trachomatous trichiasis remained above the elimination threshold (0.2% in ≥15-year-olds) and was virtually unchanged from baseline. The prevalence of trachomatous inflammation-follicular (TF) in 1-9-year-olds decreased by approximately 40% from baseline in both evaluation units but remained above the 5% TF prevalence threshold for stopping MDA. TF prevalence at impact survey was 11.5% in Kiritimati and 17.9% in Tarawa. Infection prevalence in 1-9-year-olds by PCR was 0.96% in Kiritimati and 3.3% in Tarawa. Using a multiplex bead assay to measure antibodies to the C. trachomatis antigen Pgp3, seroprevalence in 1-9-year-olds was 30.2% in Kiritimati and 31.4% in Tarawa. The seroconversion rate, in seroconversion events/100 children/year, was 9.0 in Kiritimati and 9.2 in Tarawa. Seroprevalence and seroconversion rates were both assessed by four different assays, with strong agreement between tests. These results show that, despite decreases in indicators associated with infection at impact survey, trachoma remains a public health problem in Kiribati, and provide additional information about changes in serological indicators after MDA.
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Affiliation(s)
| | | | - Emma M. Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sarah E. Gwyn
- Centers for Disease Control and Prevention, Atlanta Georgia
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia
| | - Robert Butcher
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | | | - Caleb D. Mpyet
- Department of Ophthalmology, College of Health Sciences, University of Jos; Jos, Nigeria, and Sightsavers, Nigeria Country Office, Kaduna, Nigeria
| | - Kab Tun
- Ministry of Health and Medical Services, South Tarawa, Kiribati
| | - Karana Wickens
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | | | - Rabebe Tekeraoi
- Ministry of Health and Medical Services, South Tarawa, Kiribati
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16
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Bah MM, Sakho F, Goepogui A, Nieba LC, Cisse A, Courtright P, Harte AJ, Burgert-Brucker C, Jimenez C, Lama PL, Sagno M, Bakhtiari A, Boyd S, Solomon AW, Kelly M, James F, Tenkiano MS, Harding-Esch EM, Dicko BM. The Prevalence of Trachomatous Trichiasis in People Aged 15 Years and Over in Six Evaluation Units of Gaoual, Labé, Dalaba and Beyla Districts, Guinea. Ophthalmic Epidemiol 2023:1-8. [PMID: 37377215 PMCID: PMC10581669 DOI: 10.1080/09286586.2023.2192269] [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: 07/15/2022] [Revised: 02/04/2023] [Accepted: 03/14/2023] [Indexed: 06/29/2023]
Abstract
PURPOSE Trachoma is a public health problem in 42 countries. Inflammation associated with repeated ocular infection with Chlamydia trachomatis can cause the eyelid to scar and turn inwards, resulting in the eyelashes rubbing against the eyeball, known as trachomatous trichiasis (TT). In Guinea, baseline surveys conducted in 2013 reported inflammatory trachoma prevalences below the World Health Organization (WHO) threshold for elimination, but TT prevalences above threshold. Given this epidemiological context and time since baseline survey, TT-only surveys were conducted in selected districts to determine current TT prevalence. The results of this study provide critical data for assessing Guinea's achievement of trachoma elimination targets. METHODS Four health districts, consisting of six evaluation units (EU), were surveyed. In each EU, field teams visited 29 clusters with a minimum 30 households included in each. Participants aged≥15 years were examined by certified graders trained to identify TT and determine whether management had been offered. RESULTS A total of 22,476 people were examined, with 48 TT cases across the six EUs identified. Five of six EUs had an age-and-gender adjusted TT-prevalence unknown to the health system less than 0.2%, whereas one EU, Beyla 2, had an adjusted TT prevalence of 0.24%. CONCLUSION These TT-only surveys, along with findings from other trachoma interventions, suggest that Guinea is close to achieving elimination of trachoma as a public health problem. This study demonstrates the value of undertaking TT-only surveys in settings where baseline surveys indicated active trachoma prevalences below WHO elimination threshold, but TT prevalences above it.
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Affiliation(s)
- Midiaou M. Bah
- Neglected Tropical Diseases, Sightsavers, Conakry, Guinea
| | - Fatoumata Sakho
- Ministère de la Santé, National Programme for the Control of Neglected Tropical Diseases, Conakry, Guinea
| | - André Goepogui
- Ministère de la Santé, National Programme for the Control of Neglected Tropical Diseases, Conakry, Guinea
| | - Luc C. Nieba
- Ministère de la Santé, National Programme for the Control of Neglected Tropical Diseases, Conakry, Guinea
| | | | - Paul Courtright
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Anna J. Harte
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Clara Burgert-Brucker
- Neglected Tropical Diseases, RTI International, Washington, District of Columbia, USA
| | | | - Pierre L. Lama
- Ministère de la Santé, National Programme for the Control of Neglected Tropical Diseases, Conakry, Guinea
| | - Michel Sagno
- Ministère de la Santé, National Programme for the Control of Neglected Tropical Diseases, Conakry, Guinea
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | - Sarah Boyd
- International Trachoma Initiative, Task Force for Global Health, Atlanta, Georgia, USA
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Michaela Kelly
- Neglected Tropical Diseases, Sightsavers, Haywards Heath, UK
| | - Fiona James
- Neglected Tropical Diseases, Sightsavers, Haywards Heath, UK
| | | | - Emma M. Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
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17
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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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18
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Gupta N, Vashist P, Meel R, Grover S, Jain S, Kumar D, Gupta V, Tandon R, Solomon AW. Prospective audit of the phenotype, causes and correlates of trachomatous and non- trachomatous trichiasis in a peri-elimination setting. PLoS Negl Trop Dis 2022; 16:e0011014. [PMID: 36574461 PMCID: PMC9829166 DOI: 10.1371/journal.pntd.0011014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 01/09/2023] [Accepted: 12/09/2022] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To explore the burden, clinical features and associations of trichiasis due to trachomatous and non-trachomatous aetiologies. METHODS Consenting patients presenting with trichiasis of either eyelid (of one or both eyes) attending the outpatient department, cornea and oculoplasty clinics of a tertiary eye care hospital in New Delhi between August 2018 to March 2020 were included. A comprehensive examination including visual acuity and anterior segment evaluation and photography was performed. Grade of trichiasis, laterality, presence and grade of entropion, and information on corneal opacity, conjunctival scarring, Herbert's pits, and pannus, if present, were recorded in the case record form. RESULTS Overall, 302 patients (454 eyes) with trichiasis were recruited. The most common attributed cause of upper eyelid trichiasis (276 patients, 405 eyes) was trachoma (26% of patients), followed by Stevens-Johnson syndrome (23%), blepharokeratoconjunctivitis (17%) and old age (10%). A total of 296/405 eyes (73%) had some form of corneal involvement. Trachoma was not identified as the cause of trichiasis in any eye with lower eyelid-only disease. CONCLUSION Only about a quarter of upper eyelid trichiasis in this peri-elimination setting was attributed to trachoma. A distinction between trachomatous and non-trachomatous trichiasis is imperative to meaningfully determine whether elimination of trachoma as a public health problem has occurred. These data may have implications for population-based estimates of TT prevalence in India and other peri-elimination settings.
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Affiliation(s)
- Noopur Gupta
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
- * E-mail:
| | - Praveen Vashist
- Community Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Rachna Meel
- Oculoplasty Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Sumit Grover
- Community Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Shubhi Jain
- Community Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Deepak Kumar
- Community Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Vivek Gupta
- Community Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Radhika Tandon
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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19
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Stafford E, Kot M. Optimal reduced-mixing for an SIS infectious-disease model. JOURNAL OF BIOLOGICAL DYNAMICS 2022; 16:746-765. [PMID: 36415142 DOI: 10.1080/17513758.2022.2148764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 11/12/2022] [Indexed: 06/16/2023]
Abstract
Which reduced-mixing strategy maximizes economic output during a disease outbreak? To answer this question, we formulate an optimal-control problem that maximizes the difference between revenue, due to healthy individuals, and medical costs, associated with infective individuals, for SIS disease dynamics. The control variable is the level of mixing in the population, which influences both revenue and the spread of the disease. Using Pontryagin's maximum principle, we find a closed-form solution for our problem. We explore an example of our problem with parameters for the transmission of Staphylococcus aureus in dairy cows, and we perform sensitivity analyses to determine how model parameters affect optimal strategies. We find that less mixing is preferable when the transmission rate is high, the per-capita recovery rate is low, or when the revenue parameter is much smaller than the cost parameter.
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Affiliation(s)
- Erin Stafford
- Department of Applied Mathematics, University of Washington, Seattle, WA, USA
| | - Mark Kot
- Department of Applied Mathematics, University of Washington, Seattle, WA, USA
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20
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Lynch KD, Morotti W, Brian G, Ketchup L, Kingston K, Starr M, Ware RS, Everill B, Asgar N, O'Keefe A, Whop LJ, Kaldor JM, Lambert SB. Clinical signs of trachoma and laboratory evidence of ocular Chlamydia trachomatis infection in a remote Queensland community: a serial cross-sectional study. Med J Aust 2022; 217:538-543. [PMID: 36180097 PMCID: PMC9827872 DOI: 10.5694/mja2.51735] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/03/2022] [Accepted: 08/15/2022] [Indexed: 01/12/2023]
Abstract
OBJECTIVES To compare the findings of standard clinical assessments and of complementary clinical and laboratory methods for determining whether community-wide treatment for trachoma is warranted in a remote Queensland community. DESIGN Three cross-sectional screening surveys, 2019-2021, complemented by laboratory pathology testing. SETTING Small community in northwest Queensland with geographic and cultural ties to Northern Territory communities where trachoma persists. PARTICIPANTS Children aged 1-14 years; opportunistic screening of people aged 15 years or more. MAIN OUTCOME MEASURES Prevalence of clinical signs of trachoma, Chlamydia trachomatis infection, ocular non-chlamydial infections, and seropositivity for antibodies to the C. trachomatis Pgp3 protein. RESULTS During the three surveys, 73 examinations of 58 children aged 1-4 years, 309 of 171 aged 5-9 years, and 142 of 105 aged 10-14 years for trachoma were undertaken, as were 171 examinations of 164 people aged 15 years or more; 691 of 695 examinations were of Aboriginal or Torres Strait Islander people (99%), 337 were of girls or young women (48%). Clinical signs consistent with trachomatous inflammation-follicular were identified in 5-9-year-old children 23 times (7%), including in eleven with non-chlamydial infections and one with a C. trachomatis infection. One child (10-14 years) met the criteria for trachomatous scarring. Two of 272 conjunctival swab samples (all ages) were polymerase chain reaction-positive for C. trachomatis (0.7%). Two of 147 people aged 15 years or more examined in 2019 had trichiasis, both aged 40 years or more. Seven of 53 children aged 1-9 years in 2019 and seven of 103 in 2021 were seropositive for anti-Pgp3 antibodies. CONCLUSIONS Despite the prevalence of clinical signs consistent with trachomatous inflammation-follicular among 5-9-year-old children exceeding the 5% threshold for community-wide treatment, laboratory testing indicated that childhood exposure to ocular C. trachomatis is rare in this community. Laboratory testing should be integrated into Australian trachoma guidelines.
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Affiliation(s)
- Kathleen D Lynch
- UQ Centre for Clinical ResearchUniversity of QueenslandBrisbaneQLD,Communicable Diseases Branch, Queensland HealthBrisbaneQLD
| | - Wendy Morotti
- Communicable Diseases Branch, Queensland HealthBrisbaneQLD
| | - Garry Brian
- Communicable Diseases Branch, Queensland HealthBrisbaneQLD
| | | | | | - Mitchell Starr
- St Vincent’s Centre for Applied Medical Research, St Vincent's HospitalSydneyNSW
| | - Robert S Ware
- Menzies Health Institute QueenslandGriffith UniversityBrisbaneQLD
| | - Beth Everill
- Queensland Department of Education and TrainingBrisbaneQLD
| | | | - Anne O'Keefe
- North West Hospital and Health ServiceMount IsaQLD
| | - Lisa J Whop
- National Centre for Epidemiology and Population HealthAustralian National UniversityCanberraACT
| | - John M Kaldor
- Kirby InstituteUniversity of New South WalesSydneyNSW
| | - Stephen B Lambert
- UQ Centre for Clinical ResearchUniversity of QueenslandBrisbaneQLD,Communicable Diseases Branch, Queensland HealthBrisbaneQLD,National Centre for Immunisation Research and Surveillance, Sydney Children's Hospitals NetworkSydneyNSW
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21
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Adams J, Kim SH, Solomon AW. Where should we offer mass drug administration for trachoma? Med J Aust 2022; 217:522-523. [DOI: 10.5694/mja2.51752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 09/26/2022] [Accepted: 09/26/2022] [Indexed: 11/05/2022]
Affiliation(s)
| | - Sung Hye Kim
- World Health Organization Regional Office for the Western Pacific Manila Philippines
- Hanyang University Seoul Republic of Korea
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22
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Dixon MA, Winskill P, Harrison WE, Whittaker C, Schmidt V, Flórez Sánchez AC, Cucunuba ZM, Edia-Asuke AU, Walker M, Basáñez MG. Global variation in force-of-infection trends for human T aenia solium taeniasis/cysticercosis. eLife 2022; 11:76988. [PMID: 35984416 PMCID: PMC9391040 DOI: 10.7554/elife.76988] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 08/07/2022] [Indexed: 12/01/2022] Open
Abstract
Infection by Taenia solium poses a major burden across endemic countries. The World Health Organization (WHO) 2021–2030 Neglected Tropical Diseases roadmap has proposed that 30% of endemic countries achieve intensified T. solium control in hyperendemic areas by 2030. Understanding geographical variation in age-prevalence profiles and force-of-infection (FoI) estimates will inform intervention designs across settings. Human taeniasis (HTT) and human cysticercosis (HCC) age-prevalence data from 16 studies in Latin America, Africa, and Asia were extracted through a systematic review. Catalytic models, incorporating diagnostic performance uncertainty, were fitted to the data using Bayesian methods, to estimate rates of antibody (Ab)-seroconversion, infection acquisition and Ab-seroreversion or infection loss. HCC FoI and Ab-seroreversion rates were also estimated across 23 departments in Colombia from 28,100 individuals. Across settings, there was extensive variation in all-ages seroprevalence. Evidence for Ab-seroreversion or infection loss was found in most settings for both HTT and HCC and for HCC Ab-seroreversion in Colombia. The average duration until humans became Ab-seropositive/infected decreased as all-age (sero)prevalence increased. There was no clear relationship between the average duration humans remain Ab-seropositive and all-age seroprevalence. Marked geographical heterogeneity in T. solium transmission rates indicate the need for setting-specific intervention strategies to achieve the WHO goals.
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Affiliation(s)
- Matthew A Dixon
- Department of Infectious Disease Epidemiology and London Centre for Neglected Tropical Disease Research (LCNTDR), Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.,MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.,SCI Foundation, Edinburgh House, London, United Kingdom
| | - Peter Winskill
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
| | | | - Charles Whittaker
- Department of Infectious Disease Epidemiology and London Centre for Neglected Tropical Disease Research (LCNTDR), Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.,MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
| | - Veronika Schmidt
- Department of Neurology, Center for Global Health, Technical University Munich (TUM), Munich, Germany.,Centre for Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | | | - Zulma M Cucunuba
- Department of Infectious Disease Epidemiology and London Centre for Neglected Tropical Disease Research (LCNTDR), Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.,MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
| | | | - Martin Walker
- Department of Pathobiology and Population Sciences and London Centre for Neglected Tropical Disease Research (LCNTDR), Royal Veterinary College, Hatfield, United Kingdom
| | - María-Gloria Basáñez
- Department of Infectious Disease Epidemiology and London Centre for Neglected Tropical Disease Research (LCNTDR), Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom.,MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology Faculty of Medicine, School of Public Health, Imperial College London, London, United Kingdom
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23
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Abstract
Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectious-inflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individual's lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse.
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24
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Gupta N, Yadav S, Solomon AW, Jain S, Kashyap S, Vanathi M, Tandon R. Atypical Corneal Phenotype in Patients With Trachoma and Secondary Amyloidosis. Cornea 2022; 41:609-615. [PMID: 34176916 PMCID: PMC8969838 DOI: 10.1097/ico.0000000000002791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 11/24/2022]
Abstract
PURPOSE To report clinical presentation, in vivo confocal microscopic features, and corneal phenotype in patients with trachomatous keratopathy (TK) and secondary amyloidosis. METHODS Histopathological records of all patients undergoing keratoplasty at the Dr. Rajendra Prasad Centre for Ophthalmic Sciences over a 3-year period were scanned retrospectively for a diagnosis of TK and amyloidosis. Demographic profile and details of preoperative comprehensive ophthalmic assessment were extracted. The histopathology was freshly reviewed. RESULTS Fifteen patients (29 eyes) with TK and atypical corneal involvement due to amyloid deposition were identified. Herbert's pits and upper palpebral conjunctival scarring were present in all cases. Central or total diffuse corneal scarring was present involving the anterior stroma in 5 (31%) and the full thickness of the cornea in 11 (69%) of the eyes. Eight (73%) of 11 patients with deep stromal amyloid deposits revealed bilateral, discrete, blue-white opacities at the level of deep stroma and Descemet membrane (DM). Endothelial cells were atrophic and flattened with gutta formation. Confoscans revealed hyperreflective, needle-shaped crystalline deposits of extracellular amyloid at various depths of the corneal stroma up to DM. All host corneal buttons demonstrated Congo red-positive amyloid deposits on histopathological examination. CONCLUSIONS We describe a distinct form of TK unlike the usual presentation of dense, leucomatous, vascularized corneal scarring in trachoma. We believe that amyloid deposits in DM and the corneal endothelium have not previously been reported in patients with trachoma.
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Affiliation(s)
- Noopur Gupta
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Saumya Yadav
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Anthony W. Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Avenue Appia 20, Geneva, Switzerland; and
| | - Shubhi Jain
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Seema Kashyap
- Ocular Pathology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Murugesan Vanathi
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Radhika Tandon
- Cornea, Cataract & Refractive Surgery Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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25
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Hammou J, Guagliardo SAJ, Obtel M, Razine R, Haroun AE, Youbi M, Bellefquih AM, White M, Gwyn S, Martin DL. Post-Validation Survey in Two Districts of Morocco after the Elimination of Trachoma as a Public Health Problem. Am J Trop Med Hyg 2022; 106:tpmd211140. [PMID: 35344929 PMCID: PMC9128706 DOI: 10.4269/ajtmh.21-1140] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/16/2022] [Indexed: 11/07/2022] Open
Abstract
Trachoma is the leading infectious cause of blindness. In 2016, Morocco was validated by WHO as having eliminated trachoma as a public health problem. We evaluated two previously endemic districts in Morocco for trachomatous inflammation-follicular (TF), trachomatous trichiasis (TT), and antibodies against Chlamydia trachomatis, the causative agent of trachoma. Community-based cross-sectional surveys in the districts of Boumalene Dades and Agdez included 4,445 participants for whom both questionnaire and serology data were available; 58% were aged 1-9 years. Participants had eyes examined for TF and blood collected for analysis of antibodies to the C. trachomatis antigen Pgp3 by both a multiplex bead assay (MBA) and lateral flow assay (LFA). Seroconversion rates (SCR) per 100 people per year were used to estimate changes in the force of infection using Bayesian serocatalytic models. In Agdez, TF prevalence in 1-9-year-olds was 0.3%, seroprevalence ranged from 9.4% to 11.4%, and SCR estimates ranged from 2.4 to 3.0. In Boumalene Dades, TF prevalence in 1-9-year-olds was 0.07%, and modeling data from the different assays indicated a decrease in transmission between 20 and 24 years ago. The TF data support an absence of active trachoma in the two districts examined. However, seroprevalence and SCR in younger people were higher in Agdez than Boumalene Dades, showing that there can be differences in serology metrics in areas with similar TF prevalence. Data will be included in multicountry analyses to better understand potential thresholds for serological surveillance in trachoma.
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Affiliation(s)
- Jaouad Hammou
- Faculty of Medicine and Pharmacy of Rabat, Mohammed V University, Rabat, Morocco
| | - Sarah Anne J. Guagliardo
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Majdouline Obtel
- Laboratory of Biostatistics, Clinical Research and Epidemiology, Department of Public Health, Faculty of Medicine and Pharmacy of Rabat, Mohammed V University, Rabat, Morocco
- Laboratory of Community Heath (Public Health, Preventive Medicine and Hygiene), Department of Public Health, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
| | - Rachid Razine
- Laboratory of Biostatistics, Clinical Research and Epidemiology, Department of Public Health, Faculty of Medicine and Pharmacy of Rabat, Mohammed V University, Rabat, Morocco
- Laboratory of Community Heath (Public Health, Preventive Medicine and Hygiene), Department of Public Health, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
| | - Abbas Ermilo Haroun
- Laboratory of Biostatistics, Clinical Research and Epidemiology, Department of Public Health, Faculty of Medicine and Pharmacy of Rabat, Mohammed V University, Rabat, Morocco
- Laboratory of Community Heath (Public Health, Preventive Medicine and Hygiene), Department of Public Health, Faculty of Medicine and Pharmacy, University Mohammed V, Rabat, Morocco
| | - Mohamed Youbi
- Directorate of Epidemiology and Disease Control, Ministry of Health, Rabat, Morocco
| | | | - Michael White
- Infectious Disease Epidemiology and Analytics Unit, Department of Global Health, Institute Pasteur, Paris, France
| | - Sarah Gwyn
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Diana L. Martin
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
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26
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Amoah B, Fronterre C, Johnson O, Dejene M, Seife F, Negussu N, Bakhtiari A, Harding-Esch EM, Giorgi E, Solomon AW, Diggle PJ. Model-based geostatistics enables more precise estimates of neglected tropical-disease prevalence in elimination settings: mapping trachoma prevalence in Ethiopia. Int J Epidemiol 2021; 51:468-478. [PMID: 34791259 PMCID: PMC9082807 DOI: 10.1093/ije/dyab227] [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: 07/17/2020] [Accepted: 09/29/2021] [Indexed: 12/05/2022] Open
Abstract
Background As the prevalences of neglected tropical diseases reduce to low levels in some
countries, policymakers require precise disease estimates to decide whether the set
public health targets have been met. At low prevalence levels, traditional statistical
methods produce imprecise estimates. More modern geospatial statistical methods can
deliver the required level of precision for accurate decision-making. Methods Using spatially referenced data from 3567 cluster locations in Ethiopia in the years
2017, 2018 and 2019, we developed a geostatistical model to estimate the prevalence of
trachomatous trichiasis and to calculate the probability that the trachomatous
trichiasis component of the elimination of trachoma as a public health problem has
already been achieved for each of 482 evaluation units. We also compared the precision
of traditional and geostatistical approaches by the ratios of the lengths of their 95%
predictive intervals. Results The elimination threshold of trachomatous trichiasis (prevalence ≤ 0.2% in individuals
aged ≥15 years) is met with a probability of 0.9 or more in 8 out of the 482 evaluation
units assessed, and with a probability of ≤0.1 in 469 evaluation units. For the
remaining five evaluation units, the probability of elimination is between 0.45 and
0.65. Prevalence estimates were, on average, 10 times more precise than estimates
obtained using the traditional approach. Conclusions By accounting for and exploiting spatial correlation in the prevalence data, we
achieved remarkably improved precision of prevalence estimates compared with the
traditional approach. The geostatistical approach also delivers predictions for
unsampled evaluation units that are geographically close to sampled evaluation
units.
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Affiliation(s)
- Benjamin Amoah
- Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
| | - Claudio Fronterre
- Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
| | - Olatunji Johnson
- Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
| | - Michael Dejene
- Michael Dejene Public Health Consultancy Services, Addis Ababa, Ethiopia
| | - Fikre Seife
- Disease Prevention and Control Directorate, Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Emma M Harding-Esch
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Emanuele Giorgi
- Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Peter J Diggle
- Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
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27
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Oldenburg CE, Aragie S, Amza A, Solomon AW, Brogdon J, Arnold BF, Keenan JD, Lietman TM. Can we eradicate trachoma? A survey of stakeholders. Br J Ophthalmol 2021; 105:1059-1062. [PMID: 32855161 PMCID: PMC8311100 DOI: 10.1136/bjophthalmol-2020-315815] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 07/25/2020] [Accepted: 07/27/2020] [Indexed: 12/02/2022]
Abstract
BACKGROUND/AIMS Although tremendous progress towards the 2020 goal of global elimination of trachoma as a public health problem has been made, it will not be achieved. Future targets are now being considered. One option is changing the goal to eradication. We surveyed trachoma experts to assess beliefs related to trachoma eradication and determine perceived obstacles to achieving it. METHODS We conducted a survey at the beginning of a trachoma eradication session at the 2019 Coalition for Operational Research on Neglected Tropical Diseases meeting in National Harbor, Maryland, USA. We asked respondents what the most important goal of azithromycin mass drug administration was for trachoma (control, elimination of infection or eradication) and if and when they believed trachoma eradication would occur. We then asked what the biggest obstacles were to global eradication. RESULTS Fifty-six surveys were returned (95%). Most (91%) participants reported that the most important goal of azithromycin mass drug administration was control or elimination of infection, and 24% of participants reported that global eradication was not possible. Of the 76% who reported a year by which they believed trachoma could be eradicated, most fell between 2040 and 2050. Commonly cited barriers to global eradication included lack of surveillance tools to confirm eradication or monitor for infection recrudescence (32%) and lack of resources (23%). CONCLUSIONS Development of alternative indicators for trachoma surveillance and continued investment in trachoma programmes, particularly focused support in the most heavily affected populations, might increase enthusiasm for the feasibility of eradication.
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Affiliation(s)
- Catherine E Oldenburg
- Department of Ophthalmology, University of California, San Francisco, California, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA
| | | | - Abdou Amza
- Faculté Des Sciences De La Santé, Université Abdou Moumouni De Niamey, Niamey, Niger
- Programme National De Santé Oculaire, Niamey, Niger
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Jessica Brogdon
- F.I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Benjamin F Arnold
- Department of Ophthalmology, University of California, San Francisco, California, USA
- F.I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Jeremy D Keenan
- Department of Ophthalmology, University of California, San Francisco, California, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA
- F.I. Proctor Foundation, University of California, San Francisco, California, USA
| | - Thomas M Lietman
- Department of Ophthalmology, University of California, San Francisco, California, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, California, USA
- F.I. Proctor Foundation, University of California, San Francisco, California, USA
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Astale T, Ebert CD, Nute AW, Zerihun M, Gessese D, Melak B, Sata E, Ayele Z, Ayenew G, Callahan EK, Haile M, Zeru T, Tadesse Z, Nash SD. The population-based prevalence of trachomatous scarring in a trachoma hyperendemic setting: results from 152 impact surveys in Amhara, Ethiopia. BMC Ophthalmol 2021; 21:213. [PMID: 33985443 PMCID: PMC8120834 DOI: 10.1186/s12886-021-01972-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 04/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trachomatous scarring (TS) results from repeated infection with the bacterium Chlamydia trachomatis. Pronounced scarring is an underlying cause of trachomatous trichiasis (TT) that can lead to blindness. Since the condition is irreversible, TS in adults has been considered a marker of past exposure to trachoma infection. The aim of this report was to estimate the population-based prevalence of TS within Amhara, Ethiopia, a region with a historically high burden of trachoma. METHODS District-level multi-stage cluster surveys were conducted in all districts between 2010 and 2015 to monitor the impact of approximately 5 years of trachoma interventions. Approximately 40 households were sampled per cluster and all participants ages ≥ 1 year were graded for the 5 World Health Organization simplified signs. Before each survey round, trachoma graders participated in a 7-day training and reliability exam that included cases of TS. TS prevalence estimates were weighted to account for sampling design and adjusted for age and sex using post-stratification weighting. RESULTS Across the 152 districts in Amhara, 208,510 individuals ages 1 year and older were examined for the signs of trachoma. Region-wide, the prevalence of TS was 8.2 %, (95 % Confidence Interval [CI]: 7.7-8.6 %), and the prevalence among individuals ages 15 years and older (n = 110,137) was 12.6 % (95 % CI: 12.0-13.3 %). District-level TS prevalence among individuals ages 15 years and older ranged from 0.9 to 36.9 % and was moderately correlated with district prevalence of TT (r = 0.31; P < 0.001). The prevalence of TS increased with age, reaching 22.4 % among those ages 56 to 60 years and 24.2 % among those ages 61 to 65 years. Among children ages 1 to 15 years TS prevalence was 2.2 % (95 % CI: 1.8-2.8 %), increased with age (P < 0.001), and 5 % of individuals with TS also had trachomatous inflammation-intense (TI). CONCLUSIONS These results suggest that Amhara has had a long history of trachoma exposure and that a large population remains at risk for developing TT. It is promising, however, that children, many born after interventions began, have low levels of TS compared to other known trachoma-hyperendemic areas.
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Affiliation(s)
| | - Caleb D Ebert
- F.I. Proctor Foundation, University of California, San Francisco, CA, San Francisco, USA.
| | | | | | | | | | | | | | | | | | | | - Taye Zeru
- Amhara Public Health Institute, Bahir Dar, Ethiopia
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29
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Comparison of platforms for testing antibodies to Chlamydia trachomatis antigens in the Democratic Republic of the Congo and Togo. Sci Rep 2021; 11:7225. [PMID: 33790370 PMCID: PMC8012353 DOI: 10.1038/s41598-021-86639-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 03/08/2021] [Indexed: 11/27/2022] Open
Abstract
Trachoma, caused by repeated ocular infection with Chlamydia trachomatis (Ct), is targeted for elimination as a public health problem. Serological testing for antibodies is promising for surveillance; determining useful thresholds will require collection of serological data from settings with different prevalence of the indicator trachomatous inflammation—follicular (TF). Dried blood spots were collected during trachoma mapping in two districts each of Togo and Democratic Republic of the Congo. Anti-Ct antibodies were detected by multiplex bead assay (MBA) and three different lateral flow assays (LFA) and seroprevalence and seroconversion rate (SCR) were determined. By most tests, the district with > 5% TF (the elimination threshold) had five–sixfold higher seroprevalence and tenfold higher SCR than districts with < 5% TF. The agreement between LFA and MBA was improved using a black latex developing reagent. These data show optimization of antibody tests against Ct to better differentiate districts above or below trachoma elimination thresholds.
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30
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Anderson LC, Loker ES, Wearing HJ. Modeling schistosomiasis transmission: the importance of snail population structure. Parasit Vectors 2021; 14:94. [PMID: 33536054 PMCID: PMC7860629 DOI: 10.1186/s13071-021-04587-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 01/08/2021] [Indexed: 12/14/2022] Open
Abstract
Background Schistosomiasis is a neglected tropical disease endemic in 54 countries. A major Schistosoma species, Schistosoma mansoni, is sustained via a life cycle that includes both human and snail hosts. Mathematical models of S. mansoni transmission, used to elucidate the complexities of the transmission cycle and estimate the impact of intervention efforts, often focus primarily on the human host. However, S. mansoni incurs physiological costs in snails that vary with the age of the snail when first infected. Snail demography and the age of snail infection could thus affect the force of infection experienced by humans, which is frequently used to predict the impact of various control strategies. Methods To address how these snail host and parasite interactions influence model predictions, we developed deterministic models of schistosomiasis transmission that include varying complexity in the snail population age structure. Specifically, we examined how model outputs, such as schistosome prevalence in human and snail populations, respond to the inclusion of snail age structure. Results Our models suggest that snail population age structure modifies the force of infection experienced by humans and the relationship between snail infection prevalence and corresponding human infection prevalence. There are significant differences in estimated snail infection, cercarial density and mean worm burden between models without snail population dynamics and those with snail populations, and between models with a homogeneous snail population and those with age stratification. The variation between finely age-stratified snail populations and those grouped into only juvenile and adult life stages is, however, minimal. Conclusions These results indicate that including snails and snail age structure in a schistosomiasis transmission model alters the relationship between snail and human infection prevalence. This highlights the importance of accounting for a heterogeneous intermediate host population in models of schistosomiasis transmission where the impact of proposed control measures is being considered.![]()
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Affiliation(s)
- Larissa C Anderson
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA.
| | - Eric S Loker
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Helen J Wearing
- Department of Biology, University of New Mexico, Albuquerque, NM, 87131, USA.,Department of Mathematics and Statistics, University of New Mexico, Albuquerque, NM, 87131, USA
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31
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Macleod CK, Butcher R, Javati S, Gwyn S, Jonduo M, Abdad MY, Roberts CH, Keys D, Koim SP, Ko R, Garap J, Pahau D, Houinei W, Martin DL, Pomat WS, Solomon AW. Trachoma, Anti-Pgp3 Serology, and Ocular Chlamydia trachomatis Infection in Papua New Guinea. Clin Infect Dis 2021; 72:423-430. [PMID: 31965155 PMCID: PMC7850549 DOI: 10.1093/cid/ciaa042] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 01/19/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND In Melanesia, the prevalence of trachomatous inflammation-follicular (TF) suggests that public health-level interventions against active trachoma are needed. However, the prevalence of trachomatous trichiasis is below the threshold for elimination as a public health problem and evidence of conjunctival infection with trachoma's causative organism (Chlamydia trachomatis [CT]) is rare. Here, we examine the prevalence of ocular infection with CT and previous exposure to CT in three evaluation units (EUs) of Papua New Guinea. METHODS All individuals aged 1-9 years who were examined for clinical signs of trachoma in 3 Global Trachoma Mapping Project EUs were eligible to take part in this study (N = 3181). Conjunctival swabs were collected from 349 children with TF and tested by polymerase chain reaction to assess for ocular CT infection. Dried blood spots were collected from 2572 children and tested for anti-Pgp3 antibodies using a multiplex assay. RESULTS The proportion of children with TF who had CT infection was low across all 3 EUs (overall 2%). Anti-Pgp3 seroprevalence was 5.2% overall and there was no association between anti-Pgp3 antibody level and presence of TF. In 2 EUs, age-specific seroprevalence did not increase significantly with increasing age in the 1- to 9-year-old population. In the third EU, there was a statistically significant change with age but the overall seroprevalence and peak age-specific seroprevalence was very low. CONCLUSIONS Based on these results, together with similar findings from the Solomon Islands and Vanuatu, the use of TF to guide antibiotic mass drug administration decisions in Melanesia should be reviewed.
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Affiliation(s)
- Colin K Macleod
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robert Butcher
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Sarah Javati
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Sarah Gwyn
- Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Marinjho Jonduo
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Mohammad Yazid Abdad
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
- National Centre for Infectious Diseases, Singapore
| | - Chrissy H Roberts
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Drew Keys
- Brien Holden Vision Institute Foundation, Sydney, Australia
| | | | - Robert Ko
- Department of Ophthalmology, Port Moresby General Hospital, Port Moresby, Papua New Guinea
| | - Jambi Garap
- Department of Ophthalmology, Port Moresby General Hospital, Port Moresby, Papua New Guinea
| | - David Pahau
- Department of Ophthalmology, Boram General Hospital, Wewak, Papua New Guinea
| | - Wendy Houinei
- Neglected Tropical Diseases, National Department of Health, Port Moresby, Papua New Guinea
| | - Diana L Martin
- Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - William S Pomat
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Anthony W Solomon
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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32
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Lessons learned for surveillance strategies for trachoma elimination as a public health problem, from the evaluation of approaches utilised by Guinea worm and onchocerciasis programmes: A literature review. PLoS Negl Trop Dis 2021; 15:e0009082. [PMID: 33507903 PMCID: PMC7872237 DOI: 10.1371/journal.pntd.0009082] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 02/09/2021] [Accepted: 12/17/2020] [Indexed: 11/18/2022] Open
Abstract
Introduction A number of neglected tropical diseases are targeted for elimination or eradication. An effective surveillance system is critical to determine if these goals have been achieved and maintained. Trachoma has two related but morphologically different presentations that are monitored for elimination, the active infectious form of trachoma and trachomatous trichiasis (TT), the progression of the disease. There are a number of lessons learnt from the Guinea worm surveillance system that are particularly compatible for TT surveillance and the onchocerciasis surveillance system which can provide insights for surveillance of the infectious form of trachoma. Methods/Principal findings A literature search of peer-reviewed published papers and grey literature was conducted using PUBMED and Google Scholar for articles relating to dracunculiasis or Guinea worm, onchocerciasis and trachoma, along with surveillance or elimination or eradication. The abstracts of relevant papers were read and inclusion was determined based on specified inclusion and exclusion criteria. The credibility and bias of relevant papers were also critically assessed using published criteria. A total of 41 papers were identified that were eligible for inclusion into the review. The Guinea worm programme is designed around a surveillance-containment strategy and combines both active and passive surveillance approaches, with a focus on village-based surveillance and reporting. Although rumour reporting and a monetary incentive for the identification of confirmed Guinea worm cases have been reported as successful for identifying previously unknown transmission there is little unbiased evidence to support this conclusion. More rigorous evidence through a randomised controlled trial, influenced by motivational factors identified through formative research, would be necessary in order to consider applicability for TT case finding in an elimination setting. The onchocerciasis surveillance strategy focuses on active surveillance through sentinel surveillance of villages and breeding sites. It relies on an entomological component, monitoring infectivity rates of black flies and an epidemiological component, tracking exposure to infection in humans. Challenges have included the introduction of relatively complex diagnostics that are not readily available in onchocerciasis endemic countries and target thresholds, which are practically unattainable with current diagnostic tests. Although there is utility in monitoring for infection and serological markers in trachoma surveillance, it is important that adequate considerations are made to ensure evidence-based and achievable guidelines for their utility are put in place. Conclusions/Significance The experiences of both the Guinea worm and onchocerciasis surveillance strategies have very useful lessons for trachoma surveillance, pre- and post-validation. The use of a monetary reward for identification of TT cases and further exploration into the use of infection and serological indicators particularly in a post-validation setting to assist in identifying recrudescence would be of particular relevance. The next step would be a real-world evaluation of their relative applicability for trachoma surveillance. The design of a surveillance system needs to be carefully thought out to ensure it provides sufficient evidence to determine if a disease or infection is eliminated or eradicated. If inappropriate it can lead to on-going transmission and resurgence of infection or disease or the unnecessary continuation of interventions, wasting valuable resources. Guinea worm is a disease that is painful and debilitating, for which there is no drug or vaccine. The aim is to eradicate the disease and as such the Guinea worm programme is designed around a strategy of identification of cases and their containment to prevent onward transmission. Onchocerciasis if left untreated can lead to blindness. The aim is to eliminate the disease through the interruption of transmission. A literature review was conducted to determine available evidence and identify lessons that can be learnt from the surveillance of both diseases for the design of trachoma surveillance strategies in the endgame. The potential utility of rumour reporting and a monetary incentive for the identification of a confirmed case of Guinea worm could be explored for trichiasis case finding. Trichiasis is the progression of trachoma and leads to significant ocular morbidity. The introduction of tests for infection and antibodies and the utility of sentinel surveillance as utilised for onchocerciasis are interesting considerations for active trachoma surveillance post-validation and has potential to identify recrudescence cost-effectively. The experiences of both the Guinea worm and onchocerciasis surveillance strategies have very useful lessons that can be trialled for trachoma surveillance. However, their real-world applicability and implications for trachoma need to be evaluated before any changes in guidelines are proposed.
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33
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Mwangi G, Courtright P, Solomon AW. Systematic review of the incidence of post-operative trichiasis in Africa. BMC Ophthalmol 2020; 20:451. [PMID: 33203380 PMCID: PMC7670604 DOI: 10.1186/s12886-020-01564-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 07/10/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Surgery for trichiasis is one of the pillars of the World Health Organization's strategy for global elimination of trachoma as a public health problem. A high incidence of post-operative trichiasis or other poor surgical outcomes could jeopardize these efforts. In this review, we aimed to summarize the reported incidence of post-operative trichiasis and other poor outcomes of trichiasis surgery in Africa. METHODS We conducted a systematic literature search using PubMed, Academic Search Premier, Africa-Wide Information, CINAHL and Health Source Nursing through EBSCOhost, Web of Science, and the Cochrane Central Register of Controlled Trials. Reference lists of included studies were also reviewed to identify further potentially relevant publications. All observational and interventional studies that measured post-operative trichiasis in Africa as an outcome of trichiasis surgery were included. RESULTS Thirty-five papers reporting on 22 studies (9 interventional,13 observational; total 13,737 participants) met the inclusion criteria. The reported incidence of post-operative trichiasis in the included studies ranged from 2% (at 6 weeks after bilamellar tarsal rotation) to 69% (at 3 weeks after anterior lamellar repositioning). The incidence varied by surgical procedure, study design, and length of follow-up. CONCLUSION Trichiasis surgical outcomes should be improved. National trachoma programmes could benefit from identifying and adopting strategies to improve the performance and quality of their surgical service.
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Affiliation(s)
- Grace Mwangi
- Department of Surgery, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa.
| | - Paul Courtright
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Solomon AW, Kello AB, Bangert M, West SK, Taylor HR, Tekeraoi R, Foster A. The simplified trachoma grading system, amended. Bull World Health Organ 2020; 98:698-705. [PMID: 33177759 PMCID: PMC7652564 DOI: 10.2471/blt.19.248708] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 11/27/2022] Open
Abstract
A simplified grading system for trachoma was published by the World Health Organization (WHO) in 1987. Intended for use by non-specialist personnel working at community level, the system includes five signs, each of which can be present or absent in any eye: (i) trachomatous trichiasis; (ii) corneal opacity; (iii) trachomatous inflammation—follicular; (iv) trachomatous inflammation—intense; and (v) trachomatous scarring. Though neither perfectly sensitive nor perfectly specific for trachoma, these signs have been essential tools for identifying populations that need interventions to eliminate trachoma as a public health problem. In 2018, at WHO’s 4th global scientific meeting on trachoma, the definition of one of the signs, trachomatous trichiasis, was amended to exclude trichiasis that affects only the lower eyelid. This paper presents the amended system, updates its presentation, offers notes on its use and identifies areas of ongoing debate.
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Affiliation(s)
- Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Avenue Appia 20, 1211 Geneva 27, Switzerland
| | - Amir B Kello
- World Health Organization Regional Office for Africa, Brazzaville, Congo
| | - Mathieu Bangert
- Department of Control of Neglected Tropical Diseases, World Health Organization, Avenue Appia 20, 1211 Geneva 27, Switzerland
| | - Sheila K West
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, United States of America
| | - Hugh R Taylor
- Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - Rabebe Tekeraoi
- Eye Department, Ministry of Health and Medical Services, South Tarawa, Kiribati
| | - Allen Foster
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, England
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35
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Martin DL, Saboyà-Díaz MI, Abashawl A, Alemayeh W, Gwyn S, Hooper PJ, Keenan J, Kalua K, Szwarcwald CL, Nash S, Oldenburg C, West SK, White M, Solomon AW. The use of serology for trachoma surveillance: Current status and priorities for future investigation. PLoS Negl Trop Dis 2020; 14:e0008316. [PMID: 32970672 PMCID: PMC7514076 DOI: 10.1371/journal.pntd.0008316] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Diana L Martin
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Martha Idalí Saboyà-Díaz
- Communicable Diseases and Environmental Determinants of Health Department, Pan-American Health Organization, Washington, DC, United States of America
| | - Aida Abashawl
- Berhan Public Health and Eye Care Consultancy, Addis Ababa, Ethiopia
| | - Wondu Alemayeh
- Berhan Public Health and Eye Care Consultancy, Addis Ababa, Ethiopia.,The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | - Sarah Gwyn
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Pamela J Hooper
- International Trachoma Initiative, Task Force for Global Health, Decatur, Georgia, United States of America
| | - Jeremy Keenan
- Francis I. Proctor Foundation, University of California at San Francisco, San Francisco, California, United States of America.,Department of Ophthalmology, University of California at San Francisco, San Francisco, California, United States of America
| | - Khumbo Kalua
- Department of Ophthalmology, University of Malawi, College of Medicine Blantyre, Malawi
| | - Celia Landmann Szwarcwald
- Institute of Scientific and Technological Communication and information in Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Scott Nash
- Trachoma Control Program, The Carter Center, Atlanta, Georgia, United States of America
| | - Catherine Oldenburg
- Francis I. Proctor Foundation, University of California at San Francisco, San Francisco, California, United States of America.,Department of Ophthalmology, University of California at San Francisco, San Francisco, California, United States of America.,Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, California, United States of America
| | - Sheila K West
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, Maryland, United States of America
| | - Michael White
- Malaria: Parasites & Hosts, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Kassaw MW, Abebe AM, Tegegne KD, Getu MA, Bihonegn WT. Prevalence and associations of active trachoma among rural preschool children in Wadla district, northern Ethiopia. BMC Ophthalmol 2020; 20:346. [PMID: 32842993 PMCID: PMC7449018 DOI: 10.1186/s12886-020-01585-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 07/28/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trachoma is a neglected eye disease and an important cause of preventable corneal blindness. In endemic areas, initial infection can occur in early childhood and following a recurrent episodes, it progresses to scarring and visual impairment. Trachoma disappeared from high income countries through enhancements of hygiene and sanitation but the disease is still a challenge in developing countries. In Ethiopia, data indicate that Amhara is the region with the highest prevalence of active trachoma. The aim of this study was to assess the prevalence and associations of active trachoma among rural preschool children in Wadla district, Amhara region, Ethiopia. METHODS In this study, 596 children were screened for signs of active trachoma by using cluster-sampling technique. Following pre-testing of the survey instrument in a different district, questions about socio-demographic status were delivered for heads of households. Integrated eye care workers, previously trained to undertake trachoma screening for one month, performed eye examination. The logistic regression model was used to look for associations of active trachoma. RESULTS The prevalence of active trachoma among rural preschool children in Wadla district was 22%. Low economic status (adjusted odds ratio [AOR]3.8 (95%CI 1.3-11.4), being 37-48 months old (4.2;1.5-12.0), living in a house with thatched roof (4.4;1.4-13.6), presence of flies in a home (4.6;2.1-9.9), once-weekly face-washing frequency (8.6;2.5-29.3), having a face that had not been washed for longer than a week (10.6;2.9-37.7), and not using soap (4.5;1.8-11.3) had association to active trachoma. CONCLUSION The prevalence of active trachoma among rural pre-school children in Wadla district was high. This indicates that Trachoma is still a public health problem in the district. This high prevalence calls for further interventions to prevent future trachomatis blindness.
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Affiliation(s)
| | - Ayele Mamo Abebe
- Department of nursing, Debre Berhan University, Debre Berhan, Ethiopia
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Butcher R, Tagabasoe J, Manemaka J, Bong A, Garae M, Daniel L, Roberts C, Handley BL, Hu VH, Harding-Esch EM, Bakhtiari A, Willis R, Müller A, Kaldor J, Le Mesurier R, Mabey D, Cama A, Sokana O, Taleo F, Taylor HR, Solomon AW. Conjunctival scarring, corneal pannus and Herbert's pits in adolescent children in trachoma-endemic populations of the Solomon Islands and Vanuatu. Clin Infect Dis 2020; 73:e2773-e2780. [PMID: 32776137 PMCID: PMC8563182 DOI: 10.1093/cid/ciaa1151] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Indexed: 11/21/2022] Open
Abstract
Background In the Solomon Islands and Vanuatu, the sign trachomatous inflammation—follicular (TF) is common, but ocular infection with Chlamydia trachomatis is not. It is therefore debatable whether azithromycin mass drug administration (MDA), the recommended antibiotic treatment strategy for trachoma’s elimination as a public health problem, is necessary in this setting. We set out to estimate what proportion of adolescents were at risk of progression of trachomatous scarring. Methods A cross-sectional survey was undertaken of all children aged 10–14 years resident in communities identified as high-TF clusters during previous population-based mapping. Graders examined children for clinical evidence of trachomatous scarring, pannus, and Herbert’s pits (HPs) or limbal follicles in both eyes. A dried blood spot was collected from each child and tested for antibodies to C. trachomatis. Results A total of 492 children in 24 villages of the Solomon Islands and Vanuatu were examined. In total, 35/492 (7%) of children had limbal signs (pannus and/or HPs) plus any conjunctival scarring. And 9/492 (2%) had limbal signs and moderate or severe conjunctival scarring; 22% of children were anti-Pgp3 seropositive. Conclusions Few adolescents here are at risk of future complications from trachoma, supporting the conclusion that further antibiotic MDA is not currently required for trachoma elimination purposes in these settings.
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Affiliation(s)
- Robert Butcher
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Junely Tagabasoe
- Eye Department, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Joseph Manemaka
- Health Promotion Department, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Annie Bong
- Eye Department, Vanuatu Ministry of Health, Port Vila, Vanuatu
| | - Mackline Garae
- Department of Neglected Tropical Diseases, Vanuatu Ministry of Health, Port Vila, Vanuatu
| | - Lui Daniel
- Eye Department, Vanuatu Ministry of Health, Port Vila, Vanuatu
| | - Chrissy Roberts
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Becca L Handley
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Victor H Hu
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Emma M Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Andreas Müller
- Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia.,Programme for Blindness and Visual Impairment, World Health Organization, Geneva, Switzerland
| | - John Kaldor
- Kirby Institute, University of New South Wales, Sydney, Australia
| | | | - David Mabey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anasaini Cama
- The Fred Hollows Foundation, Carlton, Victoria, Australia
| | - Oliver Sokana
- Eye Department, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Fasihah Taleo
- Department of Neglected Tropical Diseases, Vanuatu Ministry of Health, Port Vila, Vanuatu.,Country Office, World Health Organization, Port Vila, Vanuatu
| | - Hugh R Taylor
- Indigenous Eye Health, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - Anthony W Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom.,Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Macleod CK, Bailey RL, Dejene M, Shafi O, Kebede B, Negussu N, Mpyet C, Olobio N, Alada J, Abdala M, Willis R, Hayes R, Solomon AW. Estimating the Intracluster Correlation Coefficient for the Clinical Sign "Trachomatous Inflammation-Follicular" in Population-Based Trachoma Prevalence Surveys: Results From a Meta-Regression Analysis of 261 Standardized Preintervention Surveys Carried Out in Ethiopia, Mozambique, and Nigeria. Am J Epidemiol 2020; 189:68-76. [PMID: 31509177 PMCID: PMC7119302 DOI: 10.1093/aje/kwz196] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 09/03/2019] [Indexed: 11/13/2022] Open
Abstract
Sample sizes in cluster surveys must be greater than those in surveys using simple random sampling in order to obtain similarly precise prevalence estimates, because results from subjects examined in the same cluster cannot be assumed to be independent. Therefore, a crucial aspect of cluster sampling is estimation of the intracluster correlation coefficient (ρ): the degree of relatedness of outcomes in a given cluster, defined as the proportion of total variance accounted for by between-cluster variation. In infectious disease epidemiology, this coefficient is related to transmission patterns and the natural history of infection; its value also depends on particulars of survey design. Estimation of ρ is often difficult due to the lack of comparable survey data with which to calculate summary estimates. Here we use a parametric bootstrap model to estimate ρ for the ocular clinical sign “trachomatous inflammation—follicular” (TF) among children aged 1–9 years within population-based trachoma prevalence surveys. We present results from a meta-regression analysis of data from 261 such surveys completed using standardized methods in Ethiopia, Mozambique, and Nigeria in 2012–2015. Consistent with the underlying theory, we found that ρ increased with increasing overall TF prevalence and smaller numbers of children examined per cluster. Estimates of ρ for TF were independently higher in Ethiopia than in the other countries.
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Affiliation(s)
- Colin K Macleod
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Robin L Bailey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Michael Dejene
- Michael Dejene Public Health Consultancy Services, Addis Ababa, Ethiopia
| | - Oumer Shafi
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | | | - Caleb Mpyet
- Department of Ophthalmology, Queen Mamohato Memorial Hospital, Maseru, Lesotho
- Sightsavers, Kaduna, Nigeria
- Kilimanjaro Centre for Community Ophthalmology International, Division of Ophthalmology, Groote Schuur Hospital, Cape Town, South Africa
| | - Nicholas Olobio
- National Trachoma Control Program, Department of Public Health, Federal Ministry of Health, Abuja, Nigeria
| | - Joel Alada
- Department of Ophthalmology, Queen Mamohato Memorial Hospital, Maseru, Lesotho
| | - Mariamo Abdala
- Ophthalmology Department, Ministry of Health, Maputo, Mozambique
| | | | - Richard Hayes
- MRC Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anthony W Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Khan AA, Florea VV, Hussain A, Jadoon Z, Boisson S, Willis R, Dejene M, Bakhtiari A, Mpyet C, Pavluck AL, Gillani M, Qureshi B, Solomon AW. Prevalence of Trachoma in Pakistan: Results of 42 Population-Based Prevalence Surveys from the Global Trachoma Mapping Project. Ophthalmic Epidemiol 2020; 27:155-164. [PMID: 31916887 PMCID: PMC7048080 DOI: 10.1080/09286586.2019.1708120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Purpose: Previous phases of trachoma mapping in Pakistan completed baseline surveys in 38 districts. To help guide national trachoma elimination planning, we set out to estimate trachoma prevalence in 43 suspected-endemic evaluation units (EUs) of 15 further districts. Methods: We planned a population-based trachoma prevalence survey in each EU. Two-stage cluster sampling was employed, using the systems and approaches of the Global Trachoma Mapping Project. In each EU, residents aged ≥1 year living in 30 households in each of 26 villages were invited to be examined by trained, certified trachoma graders. Questionnaires and direct observation were used to evaluate household-level access to water and sanitation. Results: One EU was not completed due to insecurity. Of the remaining 42, three EUs had trichiasis prevalence estimates in ≥15-year-olds ≥0.2%, and six (different) EUs had prevalence estimates of trachomatous inflammation—follicular (TF) in 1–9-year-olds ≥5%; each EU requires trichiasis and TF prevalence estimates below these thresholds to achieve elimination of trachoma as a public health problem. All six EUs with TF prevalences ≥5% were in Khyber Pakhtunkhwa Province. Household-level access to improved sanitation ranged by EU from 6% to 100%. Household-level access to an improved source of water for face and hand washing ranged by EU from 37% to 100%. Conclusion: Trachoma was a public health problem in 21% (9/42) of the EUs. Because the current outbreak of extremely drug-resistant typhoid in Pakistan limits domestic use of azithromycin mass drug administration, other interventions against active trachoma should be considered here.
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Affiliation(s)
- Asad Aslam Khan
- Ministry of National Health Services, Regulations and Coordination, Islamabad, Pakistan.,College of Ophthalmology and Allied Vision Sciences, King Edward Medical University, Lahore, Pakistan.,Mayo Hospital, Lahore, Pakistan
| | - Victor V Florea
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Arif Hussain
- College of Ophthalmology and Allied Vision Sciences, King Edward Medical University, Lahore, Pakistan
| | - Zahid Jadoon
- Pakistan Institute of Community Ophthalmology, Hayatabad Medical Complex, Peshawar, Pakistan
| | - Sophie Boisson
- Department of Public Health, The Environment and Social Determinants of Health, World Health Organization, Geneva, Switzerland
| | - Rebecca Willis
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Michael Dejene
- Michael Dejene Public Health Consultancy Services, Addis Ababa, Ethiopia
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | - Caleb Mpyet
- Department of Ophthalmology, University of Jos, Jos, Nigeria.,Sightsavers, Kaduna, Nigeria.,Kilimanjaro Centre for Community Ophthalmology International, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Alexandre L Pavluck
- International Trachoma Initiative, Task Force for Global Health, Decatur, GA, USA
| | | | - Babar Qureshi
- Neglected Tropical Diseases, CBM, Oakington, Cambridge, UK.,Eastern Mediterranean Region Alliance for Trachoma Control, Cairo, Egypt
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland.,Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK.,London Centre for Neglected Tropical Disease Research, London, UK
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Altherr FM, Nute AW, Zerihun M, Sata E, Stewart AEP, Gessese D, Melak B, Astale T, Ayenew G, Callahan EK, Chanyalew M, Gashaw B, Waller LA, Tadesse Z, Nash SD. Associations between Water, Sanitation and Hygiene (WASH) and trachoma clustering at aggregate spatial scales, Amhara, Ethiopia. Parasit Vectors 2019; 12:540. [PMID: 31727155 PMCID: PMC6857222 DOI: 10.1186/s13071-019-3790-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 11/04/2019] [Indexed: 11/12/2022] Open
Abstract
Background Trachoma is the leading infectious cause of blindness globally. The WHO has recommended the SAFE (Surgery, Antibiotics, Facial cleanliness and Environmental improvements) strategy to eliminate trachoma as a public health problem. The F and E arms of the strategy will likely be important for sustained disease reductions, yet more evidence is needed detailing relationships between hygiene, sanitation and trachoma in areas with differing endemicity. This study addressed whether the regional differences in water, sanitation, and hygiene (WASH) variables were associated with the spatial distribution of trachomatous inflammation-follicular (TF) among children aged 1 to 9 years in the Amhara National Regional State of Ethiopia. Methods Data from 152 multi-stage cluster random trachoma surveys were used to understand the degree of clustering of trachoma on two spatial scales (district and village) in Amhara using a geographical information system and the Getis-Ord Gi* (d) statistic for local clustering. Trained and certified graders examined children for the clinical signs of trachoma using the WHO simplified system. Socio-demographic, community, and geoclimatic factors thought to promote the clustering of the disease were included as covariates in a logistic regression model. Results The mean district prevalence of TF among children aged 1 to 9 years in Amhara was 25.1% (standard deviation = 16.2%). The spatial distribution of TF was found to exhibit global spatial dependency with neighboring evaluation units at both district and village level. Specific clusters of high TF were identified at both the district and the village scale of analysis using weighted estimates of the prevalence of the disease. Increased prevalence of children without nasal and ocular discharge as well as increased prevalence of households with access to a water source within 30 minutes were statistically significantly negatively associated with clusters of high TF prevalence. Conclusions Water access and facial cleanliness were important factors in the clustering of trachoma within this hyperendemic region. Intensified promotion of structural and behavioral interventions to increase WASH coverage may be necessary to eliminate trachoma as a public health problem in Amhara and perhaps other hyper-endemic settings.
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WoldeKidan E, Daka D, Legesse D, Laelago T, Betebo B. Prevalence of active trachoma and associated factors among children aged 1 to 9 years in rural communities of Lemo district, southern Ethiopia: community based cross sectional study. BMC Infect Dis 2019; 19:886. [PMID: 31651236 PMCID: PMC6813116 DOI: 10.1186/s12879-019-4495-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 09/23/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trachoma, caused by Chlamydia trachomatis is the leading infectious cause of blindness. It is transmitted via personal contact with infected ocular and nasal secretions by hands, fomites and eye- seeking flies. Active trachoma is more common among children aged 1 to 9 years. The objective of this study was determining the prevalence of active trachoma and associated factors among children aged 1 to 9 years in rural community of Lemo district. METHODS Community-based cross-sectional study was conducted from March to April, 2018 in rural community of Lemo district. Multistage sampling technique was used to select 589 study participants. Data were collected by using structured pre-tested questionnaire, physical examination and observation. Binocular loupe was used to identify active trachoma cases. The data were entered by using EPi-data version 3.1 and analyzed by SPSS. Binary logistic regression was used to assess factors associated with active trachoma. Variables with p-value < 0.05 in the multivariable analysis were used to declare significance of association. RESULT Eighty seven (15.2%) children were positive for active trachoma. Absence of solid waste disposal pit (AOR = 2.20, 95% CI (1.12-4.37), do not use latrine as reported by respondent (AOR = 7.53, 95% CI (2.86-19.84), do not use soap for face washing as reported by respondent (AOR =2.3, 95% CI (1.32-4.12), washing face frequency as reported by respondent (AOR = 1.86, 95% CI (1.06-3.26), and family size greater than five (AOR = 1.96, 95% CI (1.06-3.67) were significantly associated with active trachoma. CONCLUSION Active trachoma among children aged 1 to 9 years is high. Do not use latrine, do not use soap for face washing, and face washing frequency in a day as reported by respondents and family size were associated with active trachoma. Access to adequate water and sanitation can be important components in working towards eliminating trachoma as a public health problem. Therefore, prompt measures must be taken by concerned bodies to increase access to adequate water and sanitation facilities.
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Affiliation(s)
- Endale WoldeKidan
- Public health emergency management, Hadiya zone health department, Hossana, Ethiopia
| | - Deresse Daka
- Department of medical laboratory, Hawassa University, Hawassa, Ethiopia
| | - Deresse Legesse
- Department of epidemiology, Hawassa University, Hawassa, Ethiopia
| | - Tariku Laelago
- Department of nursing, Wachemo University, Durame campus, Durame, Ethiopia
| | - Bealu Betebo
- Public health emergency management, Hadiya zone health department, Hossana, Ethiopia
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Macleod CK, Binnawi KH, Elshafie BE, Sadig HE, Hassan A, Cocks N, Willis R, Chu B, Solomon AW. Unimproved water sources and open defecation are associated with active trachoma in children in internally displaced persons camps in the Darfur States of Sudan. Trans R Soc Trop Med Hyg 2019; 113:599-609. [PMID: 31612959 PMCID: PMC6792159 DOI: 10.1093/trstmh/trz042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 04/01/2019] [Accepted: 05/30/2019] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To estimate the proportion of children with trachomatous inflammation-follicular (TF) and adults with trachomatous trichiasis (TT) in internally displaced persons (IDP) camps in the Darfur States of Sudan and to evaluate associated risk factors. METHODS IDP camps were identified from government census data. We conducted a subanalysis of data collected in these camps during 2014-2015 as part of surveys covering 37 districts of the Darfur States within the Global Trachoma Mapping Project. A random-effects hierarchical model was used to evaluate factors associated with TF in children or TT in adults. RESULTS Thirty-six IDP camps were represented in the survey data, in which 1926 children aged 1-9 y were examined, of whom 38 (8%) had TF. Poor sanitation, younger age and living in a household that purchased water from a vendor were associated with TF in children aged 1-9 y. Of 2139 individuals examined aged ≥15 y, 16 (0.7%) had TT. TT was strongly independently associated with being older and living alone. CONCLUSION Trachoma is found at low levels in these camps, but still at levels where intervention is needed. Disease elimination in conflict-related settings presents a unique challenge for the trachoma community, and may require an innovative approach. Understanding how best to undertake trachoma elimination interventions in these areas should be prioritized.
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Affiliation(s)
- Colin K Macleod
- Clinical Research Department, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK
| | - Kamal Hashim Binnawi
- National Program for Prevention of Blindness, Federal Ministry of Health, PO Box 303 Khartoum, Sudan
- Department of Ophthalmology, Al Neelain University, Khartoum, Sudan
| | - Balgesa Elkheir Elshafie
- National Program for Prevention of Blindness, Federal Ministry of Health, PO Box 303 Khartoum, Sudan
| | - Husam Eldin Sadig
- Faculty of Mathematical Sciences and Statistics, Al-Neelain University, Sudan
| | | | - Naomi Cocks
- Clinical Research Department, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK
| | - Rebecca Willis
- Task Force for Global Health, 330 W Ponce de Leon Ave, Decatur, GA, USA
| | - Brian Chu
- Task Force for Global Health, 330 W Ponce de Leon Ave, Decatur, GA, USA
| | - Anthony W Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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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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Mwale C, Mumbi W, Funjika M, Sokesi T, Silumesii A, Mulenga M, Mutati G, Kwendakwema D, Chelu C, Adamu Y, Alemayehu W, Al-Khatib T, Bakhtiari A, Dejene M, Massae PA, Mpyet C, Nwosu C, Willis R, Courtright P, Solomon AW. Prevalence of Trachoma in 47 Administrative Districts of Zambia: Results of 32 Population-Based Prevalence Surveys. Ophthalmic Epidemiol 2019; 25:171-180. [PMID: 30806543 PMCID: PMC6444202 DOI: 10.1080/09286586.2018.1546880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Purpose: A number of previous administrative-district-level baseline trachoma prevalence estimates in Zambia required verification. We used methodologies and systems for trachoma surveys considered to represent international best practice in order to generate reliable estimates of the prevalence of trachoma. Methods: Between March 2016 and July 2017, we undertook 32 population-based prevalence surveys covering 47 administrative districts. In each of the 32 evaluation units (EUs), we selected 31 households in each of 24 clusters. In selected households, trained, certified graders examined all residents aged 1 year and above for evidence of trachomatous inflammation—follicular (TF) and trichiasis. In eyes that had trichiasis, the presence or absence of trachomatous scarring (TS) was recorded, and the subject was asked about previous trichiasis management recommendations from health workers. Results: Five EUs (encompassing seven administrative districts) had prevalence estimates of trichiasis+TS unknown to the health system in ≥15-year-olds of ≥0.2%, and require public-health-level implementation of trichiasis surgery services. Eleven EUs (encompassing 16 administrative districts) had TF prevalence estimates in 1–9-year-olds of ≥5%. Intervention with the A, F and E components of the SAFE strategy for trachoma elimination is required for nearly 1.5 million people. Conclusion: Trachoma is a public health problem in some parts of Zambia. The Ministry of Health will continue to partner with other stakeholders to implement the multi-sectoral SAFE strategy. Consideration should be given to re-surveying other suspected-endemic administrative districts in which surveys using older methodologies returned TF prevalence estimates ≥5%.
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Affiliation(s)
- Consity Mwale
- a Lusaka Provincial Health Office , Lusaka , Zambia.,b University Teaching Eye Hospital , Lusaka , Zambia
| | - Willard Mumbi
- c Ophthalmology Unit , Kabwe General Hospital , Kabwe , Zambia
| | - Misa Funjika
- d Ophthalmology Unit , Ndola Teaching Hospital , Ndola , Zambia
| | - Teddy Sokesi
- d Ophthalmology Unit , Ndola Teaching Hospital , Ndola , Zambia
| | | | - Muma Mulenga
- b University Teaching Eye Hospital , Lusaka , Zambia
| | - Grace Mutati
- b University Teaching Eye Hospital , Lusaka , Zambia
| | | | | | - Yilikal Adamu
- g Department of Ophthalmology, Faculty of Medicine , Addis Ababa University , Addis Ababa , Ethiopia
| | - Wondu Alemayehu
- h The Fred Hollows Foundation , Addis Ababa , Ethiopia.,i Berhan Public Health and Eye Care Consultancy , Addis Ababa , Ethiopia
| | - Tawfik Al-Khatib
- j Prevention of Blindness Program , Ministry of Public Health & Population , Sana'a , Yemen.,k Department of Ophthalmology, College of Medicine , University of Sana'a , Sana'a , Yemen.,l Eye Unit , Al-Thawra Hospital , Sana'a , Yemen
| | | | - Michael Dejene
- n Michael Dejene Public Health Consultancy Services , Addis Ababa , Ethiopia
| | | | - Caleb Mpyet
- p Department of Ophthalmology , University of Jos , Jos , Nigeria.,q Sightsavers , Kaduna , Nigeria.,r Kilimanjaro Centre for Community Ophthalmology International, Division of Ophthalmology , University of Cape Town , Cape Town , South Africa
| | | | | | - Paul Courtright
- r Kilimanjaro Centre for Community Ophthalmology International, Division of Ophthalmology , University of Cape Town , Cape Town , South Africa
| | - Anthony W Solomon
- s Clinical Research Department , London School of Hygiene & Tropical Medicine , London , UK.,t Department of Control of Neglected Tropical Diseases , World Health Organization , Geneva , Switzerland
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Alada JJ, Mpyet C, Florea VV, Boisson S, Willis R, Muhammad N, Bakhtiari A, Adamu MD, Pavluck AL, Umar MM, Isiyaku S, William A, Oyinloye FOP, Olobio N, Solomon AW. Prevalence of and risk factors for trachoma in Kwara state, Nigeria: Results of eight population-based surveys from the Global Trachoma Mapping Project. Ophthalmic Epidemiol 2019; 25:53-61. [PMID: 30806548 PMCID: PMC6444274 DOI: 10.1080/09286586.2018.1437188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Purpose: To determine the prevalence of and risk factors for trachoma in selected local government areas (LGAs) of Kwara State, Nigeria. Methodology: Population-based cross-sectional surveys were conducted in eight LGAs of Kwara State using Global Trachoma Mapping Project (GTMP) protocols. In each LGA, 25 villages were selected using probability-proportional-to-size sampling; 25 households were selected from each village using compact segment sampling. 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. Water, sanitation, and hygiene (WASH) data were also collected. Results: A total of 28,506 residents were enumerated in 4769 households across the eight LGAs. TF prevalence in children aged 1–9 years ranged from 0.2% (95% CI 0.0–0.3%) to 1.3% (95% CI 0.7–2.1%), while trichiasis prevalence in persons ≥15 years was <0.2% in each LGA. Access to improved water source was the lowest in Edu (62%), while access to improved sanitation facilities was the lowest in Asa (6%) and the highest in Ilorin East (64%). Children aged 1–4 years had 0.63 (95% CI 0.40–0.99) times lower odds of having TF compared to children aged 5–9 years. Children in households with ≥5 resident 1–9-year-old children had 1.63 (95% CI 1.02–2.60) times greater odds of having TF compared to those in households with <5 resident children. Conclusion: Trachoma is not a public health problem in Kwara State. Provision of adequate water and sanitation services should be a priority here, as a foundation for the health of the population.
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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, Environmental and Social Determinants of Health , World Health Organization , Geneva , Switzerland
| | | | - 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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46
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Mpyet C, Muhammad N, Adamu MD, Ladan M, Willis R, Umar MM, Alada J, Aliero AA, Bakhtiari A, Flueckiger RM, Olobio N, Nwosu C, Damina M, Gwom A, Labbo AA, Boisson S, Isiyaku S, William A, Rabiu MM, Pavluck AL, Gordon BA, Solomon AW. Impact Survey Results after SAFE Strategy Implementation in 15 Local Government Areas of Kebbi, Sokoto and Zamfara States, Nigeria. Ophthalmic Epidemiol 2019; 25:103-114. [PMID: 30806537 PMCID: PMC6444276 DOI: 10.1080/09286586.2018.1481984] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Purpose: To determine prevalence of trachoma after interventions in 15 local government areas (LGAs) of Kebbi, Sokoto and Zamfara States, Nigeria. Methods: A population-based impact survey was conducted in each LGA using Global Trachoma Mapping Project (GTMP) protocols. In each LGA, 25 villages were selected, except in Arewa LGA, where we selected 25 villages from each of four subunits to obtain finer-resolution prevalence information. Villages were selected with probability proportional to size. In each village, 25 households were enrolled and all consenting residents aged ≥1 year were examined by GTMP-certified graders for trachomatous inflammation—follicular (TF) and trachomatous trichiasis (TT). Information on sources of household water and types of sanitation facilities used was collected through questioning and direct observation. Results: The number of households enrolled per LGA ranged from 623 (Kware and Tangaza) to 2488 (Arewa). There have been marked reductions in the prevalence of TF and TT since baseline surveys were conducted in all 15 LGAs. Eight of the 15 LGAs have attained TF prevalences <5% in children, while 10 LGAs have attained TT prevalences <0.2% in persons aged ≥15 years. Between 49% and 96% of households had access to water for hygiene purposes within 1 km of the household, while only 10–59% had access to improved sanitation facilities. Conclusion: Progress towards elimination of trachoma has been made in these 15 LGAs. Collaboration with water and sanitation agencies and community-based trichiasis surgery are still needed in order to eliminate trachoma by the year 2020.
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Affiliation(s)
- Caleb Mpyet
- a Department of Ophthalmology , Jos University Teaching Hospital , Jos , Nigeria.,b Sightsavers , Kaduna , Nigeria.,c Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology , University of Cape Town , Cape Town , South Africa
| | - Nasiru Muhammad
- d Ophthalmology Unit, Surgery Department , Usmanu Dan Fodiyo University , Sokoto , Nigeria
| | - Mohammed Dantani Adamu
- d Ophthalmology Unit, Surgery Department , Usmanu Dan Fodiyo University , Sokoto , Nigeria
| | | | | | | | - Joel Alada
- a Department of Ophthalmology , Jos University Teaching Hospital , Jos , Nigeria.,h Department of Ophthalmology , Jos University Teaching Hospital , Jos , Nigeria
| | | | | | | | - Nicholas Olobio
- j National Trachoma Control Program, Department of Public Health , Federal Ministry of Health , Abuja , Nigeria
| | | | | | | | | | - Sophie Boisson
- l Department of Public Health, the Environment and Social Determinants of Health , World Health Organization , Geneva , Switzerland
| | | | | | | | | | - Bruce A Gordon
- l Department of Public Health, the Environment and Social Determinants of Health , World Health Organization , Geneva , Switzerland
| | - Anthony W Solomon
- n Clinical Research Department , London School of Hygiene & Tropical Medicine , London , United Kingdom.,o London Centre for Neglected Tropical Disease Research , London , United Kingdom.,p Department of Control of Neglected Tropical Diseases , World Health Organization , Geneva , Switzerland
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47
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Flueckiger RM, Giorgi E, Cano J, Abdala M, Amiel ON, Baayenda G, Bakhtiari A, Batcho W, Bennawi KH, Dejene M, Elshafie BE, Elvis AA, François M, Goepogui A, Kalua K, Kebede B, Kiflu G, Masika MP, Massangaie M, Mpyet C, Ndjemba J, Ngondi JM, Olobio N, Turyaguma P, Willis R, Yeo S, Solomon AW, Pullan RL. Understanding the spatial distribution of trichiasis and its association with trachomatous inflammation-follicular. BMC Infect Dis 2019; 19:364. [PMID: 31039737 PMCID: PMC6492377 DOI: 10.1186/s12879-019-3935-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 03/24/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Whilst previous work has identified clustering of the active trachoma sign "trachomatous inflammation-follicular" (TF), there is limited understanding of the spatial structure of trachomatous trichiasis (TT), the rarer, end-stage, blinding form of disease. Here we use community-level TF prevalence, information on access to water and sanitation, and large-scale environmental and socio-economic indicators to model the spatial variation in community-level TT prevalence in Benin, Cote d'Ivoire, DRC, Guinea, Ethiopia, Malawi, Mozambique, Nigeria, Sudan and Uganda. METHODS We fit binomial mixed models, with community-level random effects, separately for each country. In countries where spatial correlation was detected through a semi-variogram diagnostic check we then fitted a geostatistical model to the TT prevalence data including TF prevalence as an explanatory variable. RESULTS The estimated regression relationship between community-level TF and TT was significant in eight countries. We estimate that a 10% increase in community-level TF prevalence leads to an increase in the odds for TT ranging from 20 to 86% when accounting for additional covariates. CONCLUSION We find evidence of an association between TF and TT in some parts of Africa. However, our results also suggest the presence of additional, country-specific, spatial risk factors which modulate the variation in TT risk.
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Affiliation(s)
| | - Emanuele Giorgi
- Lancaster Medical School, Lancaster University, Lancaster, Lancashire, UK
| | - Jorge Cano
- London School of Hygiene and Tropical Medicine, London, UK
| | - Mariamo Abdala
- Ophthalmology Department, Ministry of Health, Maputo, Mozambique
| | | | | | | | - Wilfrid Batcho
- Programme National de Lutte contre les Maladies Transmissibles, Ministère de la Santé, Cotonou, Benin
| | | | - Michael Dejene
- Michael Dejene Public Health Consultancy Services, Addis Ababa, Ethiopia
| | | | - Aba Ange Elvis
- Programme National de la Santé Oculaire et de la lutte contre l'Onchocercose, Abidjan, Côte d'Ivoire
| | - Missamou François
- Direction de Lutte contre la Maladie, Kinshasa, Ministere de la Santé Publique, Kinshasa, Democratic Republic of Congo
| | - André Goepogui
- Programmes National de Lutte contre l'Onchocercoses et les autres Maladies Tropicales Négligées, Ministère de la Sante, Conakry, Guinea
| | - Khumbo Kalua
- Blantyre Institute for Community Outreach, Blantyre, Malawi
| | | | - Genet Kiflu
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | | | - Caleb Mpyet
- Sightsavers Nigeria, Kaduna, Nigeria.,Department of Ophthalmology, Jos University, Jos, Nigeria
| | - Jean Ndjemba
- Direction de Lutte contre la Maladie, Kinshasa, Ministere de la Santé Publique, Kinshasa, Democratic Republic of Congo
| | | | - Nicholas Olobio
- Nigeria Trachoma Elimination Program, Federal Ministry of Health, Abuja, Nigeria
| | | | | | - Souleymane Yeo
- Programme National de la Santé Oculaire et de la lutte contre l'Onchocercose, Abidjan, Côte d'Ivoire
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48
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Solomon AW, Bella ALF, Negussu N, Willis R, Taylor HR. How much trachomatous trichiasis is there? A guide to calculating district-level estimates. COMMUNITY EYE HEALTH 2019; 31:S5-S8. [PMID: 31086446 PMCID: PMC6390516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anthony W Solomon
- Medical Officer for Trachoma: Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | | | - Nebiyu Negussu
- Neglected Tropical Diseases Team Leader: Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Rebecca Willis
- Data and Analytics Team Manager: International Trachoma Initiative, Task Force for Global Health, Decatur GA, USA
| | - Hugh R Taylor
- Harold Mitchell Professor of Indigenous Eye Health: University of Melbourne, Melbourne, Australia
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49
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Macleod CK, Porco TC, Dejene M, Shafi O, Kebede B, Negussu N, Bero B, Taju S, Adamu Y, Negash K, Haileselassie T, Riang J, Badei A, Bakhtiari A, Willis R, Bailey RL, Solomon AW. Optimising age adjustment of trichiasis prevalence estimates using data from 162 standardised surveys from seven regions of Ethiopia. Ophthalmic Epidemiol 2018; 26:161-168. [PMID: 30592237 PMCID: PMC6532728 DOI: 10.1080/09286586.2018.1555262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
PURPOSE The prevalence of trichiasis is higher in females and increases markedly with age. Surveys carried out in the daytime, particularly in developing countries, are prone to find older individuals and females at home at the time of the survey. Population-level trichiasis estimates should adjust sample proportions to reflect the demographic breakdown of the population, although the most accurate method of doing this is unclear. METHODS Having obtained data from 162 surveys carried out in Ethiopia as part of the Global Trachoma Mapping Project from 2012 to 2015, we used internal validation with both Brier and Logarithmic forecast scoring to test stratification models to identify those models with the highest predictive accuracy. Selection of partitions was undertaken by both simple random sampling (SRS) and cluster sampling (CS) over 8192 selections. RESULTS A total of 4529 (1.9%) cases of trichiasis were identified from 241,139 individuals aged ≥15 years from a total of 4210 kebeles and 122,090 households visited. Overall, the binning method using 5-year bands from age 15 to 69 years, with coarser binning in 20-year age-bands above this age, provided the best predictive accuracy, in both SRS and CS methodologies and for both the Brier and Logarithmic scoring rules. CONCLUSION The greatest predictive accuracy for trichiasis estimates was found by adjusting for sex and in 5-year age-bands from the age of 15 to 69 years and in 20-year age-bands in those aged 70 years and greater. Trichiasis surveys attempting to make population-level inferences should use this method to optimise surgery backlog estimates.
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Affiliation(s)
- Colin K Macleod
- a Clinical Research Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Travis C Porco
- b Francis I. Proctor Foundation, Department of Ophthalmology , University of California, San Francisco , San Francisco , USA.,c Department of Epidemiology and Biostatistics , University of California, San Francisco , San Francisco , USA
| | - Michael Dejene
- d Michael Dejene Public Health Consultancy Services , Addis Ababa , Ethiopia
| | - Oumer Shafi
- e Federal Ministry of Health , Addis Ababa , Ethiopia
| | - Biruck Kebede
- e Federal Ministry of Health , Addis Ababa , Ethiopia
| | | | - Berhanu Bero
- f The Fred Hollows Foundation Ethiopia , Addis Ababa , Ethiopia
| | - Sadik Taju
- g Department of Ophthalmology , Addis Ababa University , Addis Ababa , Ethiopia
| | - Yilikal Adamu
- g Department of Ophthalmology , Addis Ababa University , Addis Ababa , Ethiopia
| | | | | | - John Riang
- j Gambella Regional Health Bureau , Gambella , Ethiopia
| | - Ahmed Badei
- k Department of Disease Prevention , Somali Regional State Health Bureau , Jigjiga , Ethiopia
| | - Ana Bakhtiari
- l Task Force for Global Health , Decatur , Georgia , USA
| | - Rebecca Willis
- l Task Force for Global Health , Decatur , Georgia , USA
| | - Robin L Bailey
- a Clinical Research Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Anthony W Solomon
- a Clinical Research Department , London School of Hygiene & Tropical Medicine , London , UK.,m Department of Control of Neglected Tropical Diseases , World Health Organization , Geneva , Switzerland
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50
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Tesfazion A, Zecarias A, Zewengiel S, Willis R, Mebrahtu G, Capa E, Mpyet C, Al-Khatib T, Courtright P, Solomon AW. Progress Towards Elimination of Trachoma as a Public Health Problem in Eritrea: Results of a Systematic Review and Nine Population-based Prevalence Surveys Conducted in 2014. Ophthalmic Epidemiol 2018; 25:121-130. [PMID: 30806541 PMCID: PMC6444204 DOI: 10.1080/09286586.2018.1545036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 09/21/2018] [Accepted: 11/01/2018] [Indexed: 11/16/2022]
Abstract
PURPOSE To assess Eritrea's progress towards elimination of trachoma as a public health problem, we reviewed and compiled current knowledge on the distribution and burden of trachoma in Eritrea, then undertook further population-based surveys where indicated, with support from the Global Trachoma Mapping Project (GTMP). METHODS For the systematic review, undertaken in March 2014, we searched (1) PubMed, using the terms ((blind* or trachoma or trichiasis) AND Eritrea); (2) the online database of rapid assessments of avoidable blindness; (3) our own grey literature collections; and (4) the Global Atlas of Trachoma database. In June and July 2014, we conducted nine population-based prevalence surveys, for each of which 30 villages were systematically selected with probability proportional to population size; in each village, 30 households were systematically selected. All consenting residents of selected households aged ≥1 year were examined by GTMP-certified graders for signs of trachoma. Data on household-level access to water and sanitation were also collected. RESULTS One previous rapid assessment of avoidable blindness, three peer-reviewed publications, and two grey literature reports detailing sets of trachoma prevalence surveys conducted in 2006 and 2011, respectively, were located. Post-intervention impact surveys were needed in seven evaluation units (EUs, framed at sub-Zoba-level: population range 40,000-120,000) of Debub and Northern Red Sea, while baseline surveys were needed in two EUs of Anseba. Four of the seven impact survey EUs and both baseline survey EUs returned trachomatous inflammation-follicular prevalences in 1-9-year-olds of ≥5%; six of the seven impact survey EUs and one of the two baseline survey EUs returned trichiasis prevalences in ≥15-year-olds of ≥0.2%. The prevalence of access to water and sanitation varied widely between EUs. CONCLUSION Interventions are still required in Eritrea to eliminate trachoma as a public health problem. Data from these surveys will guide the Ministry of Health to undertake programme planning using a sound evidence base.
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Affiliation(s)
- Andeberhan Tesfazion
- National Program for the Prevention of Blindness, Ministry of Health, Asmara, Eritrea
| | - Alem Zecarias
- National Program for the Prevention of Blindness, Ministry of Health, Asmara, Eritrea
| | - Solomon Zewengiel
- National Program for the Prevention of Blindness, Ministry of Health, Asmara, Eritrea
| | | | | | - Eva Capa
- The Fred Hollows Foundation, Sydney, Australia
| | - Caleb Mpyet
- Department of Ophthalmology, University of Jos, Jos, Nigeria
- Sightsavers, Kaduna, Nigeria
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Tawfik Al-Khatib
- Department of Ophthalmology, College of Medicine, University of Sana’a, Sana’a, Yemen
- Prevention of Blindness Program, Ministry of Public Health & Population, Sana’a, Yemen
- Eye Unit, Al-Thawra Hospital, Sana’a, Yemen
| | - Paul Courtright
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Anthony W. Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
- London Centre for Neglected Tropical Diseases Research, London, UK
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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